BrainEthics

We are moving!

2006-03-20T17:31:00.000+01:00

WE HAVE MOVED TO A NEW LOCATION:

http://brainethics.wordpress.com/

PLEASE UPDATE YOUR BOOKMARKS.

Oh no, I'm going to get in trouble!

2006-03-17T13:15:00.000+01:00

As discussed before here on the blog, imaging studies by Josh Greene, Jorge Moll and others have demonstrated that emotional responses play a pivotal role in forming moral judgments. A new study by Sylvie Berthoz adds further information to this growing story.

Berthoz and her colleagues had subjects read short stories describing transgressions of social rules. The stories either described situations where (1) the subject was the agent of transgression, and the violations was accidental, or situations where (2) the protagonist was another person than the subject, and the violations was accidental, or situations where (3) the subject was the agent of transgression, and the violations was intentional, or situations where (4) the protagonist was another person than the subject, and the violation was intentional. Thus, Berthoz et al. were able to contrast intentional moral transgressions performed by one self from transgressions performed by others, or from accidental transgressions.

This contrast showed significant bilateral amygdala activation, and Berthoz et al. speculate that such activation may be related to one's anticipation of possible punishment as a consequence of one's own immoral behaviour. This suggestion, of course, squares well with ideas from the emerging field of social neuroscience - especially the hypothesis that social cooperation rests upon a tit-for-tat regime: If I share my ressources with you, I expect something in return. If I don't get anything back, I will punish you. It is pretty clear, as well, that the back-bone of the success of such social behaviour is the brain's reward and punishment system: The expectancy of a return is modulated by the reward system, and the anticipation of a punishment - which works to keep you from cheating the other members of your social group - is modulated by the punishment system, including the amygdala.

Now, it would be very interesting to apply a genetic analysis to this result. Maybe we would then find a similar variance as reported by Hariri with regard to serotonin re-uptake and mood? That is, some people may be more afraid of transgressing moral rules than others due to a difference in amygdala activity. It is rather obvious, after all, that some people won't loose any sleep over sticking it to you!

Reference

Berthoz, S. et al. (2006): Affective response to one's own moral violations. To appear in NeuroImage.

Hariri review in TICS

2006-03-16T11:10:00.000+01:00

If you have read Thomas' fine introduction to Ahmad Hariri's work on the link between gene expression, serotonin re-uptake and emotion, you may be interested in hearing more about the story from the horse's own mouth. If so, check out this new review, in press for publication in the April issue of Trends in Cognitive Science.

Reference

Hariri, A. & Holmes, A. (2006): Genetics of emotional regulation: the role of the serotonin transporter in neural function. To appear in Trends in Cognitive Science.

Genes, brain/mind and behaviour

2006-03-15T15:20:00.000+01:00

This is a new conference on combining the knowledge from genetics, neuroimaging and behavioural science. A brief look at the program is enough: I'm going!

7th EMBL/EMBO Joint Conference 2006
3-4 November 2006, EMBL Heidelberg, Germany

Genes, brain/mind and behaviour

Research in the life sciences is revealing how genes are differentially expressed in the brain and how types of behavior reflect the functioning of different neural networks. Scientists are also exploring the relationship between the neurophysiology of the brain and the nature of consciousness.

Science and technology always work in tandem. Neurotechnology refers to the set of tools that have been developed to analyze and influence the human nervous system, especially the brain. We would like to assess the uses that are – or could in the future be - made of new neurological knowledge and technologies. What are the consequences when biochemical solutions to behavioral problems such as depression, addiction, or eating disorders take precedence over attempts to repair the social environment, or defective inter-personal relations? How do we avert the risk of psychopharmacology being abused for neurochemical enhancement?

While new knowledge coming out of the neurosciences has an enormous potential for beneficial applications in diverse fields, treating or manipulating the mind will also have important social, legal and bioethical implications. These are some of the main issues that will be the focus of the next inter-disciplinary EMBL/EMBO Science and Society conference in 2006 in Heidelberg, Germany.

Programme

Poster [2MB]

Normative brains and group studies

2006-03-15T14:28:00.000+01:00

In a NeuroImage article this February, Krishnan et al. demonstrate how poor spatial normalization can be for the hippocampus. Spatial normalization is an image processing step applied in neuroimaging when typically you are doing group studies. As it says on Wikipedia.com:

Human brains differ in size and shape, and one goal of spatial normalization is to deform human brain scans so one location in one subject's brain scan corresponds to the same location in another subject's brain scan.

Human brains are like fingerprints. On a general level they are alike, but they differ significantly when we look at the details. There are large individual differences if we look at where sulci and gyri appear and disappear in the brain; even whether you have one or two sulci.

Krishnan et al. have looked at the hippocampus, and found large variations in the position and extent of spatial normalization, not only due to sample size (i.e. how many subjects were included), but also when comparing the operation in patients with Mild Cognitive Impairment and healthy subjects. Put another way, if you do spatial normalization -- which you do if you want to compare groups at the brain level -- the operation may induce a bias in your results. For example, it may lead you to think that the loss of hippocampal gray matter is larger than it actually is.

To open up the lid slightly to one of my forthcoming publications, we have looked at more structures of the medial temporal lobe, including the temporopolar, entorhinal, perirhinal and parahippocampal cortex, as well as the amygdala and hippocampus. We have found that spatial normalization of these areas leads to significant dicplacement of the different structures. It's sometimes so bad that what is identified as the perirhinal cortex in the original brain (native space) is partly displaced into the hippocampus.

Here is an image of the coregistration pandemonium in the medial temporal lobe. It shows the coregistration of the left perirhinal cortex in six subjects. The structure was drawn as a region of interest and then normalized according to standard SPM warping:

Quite a mess, right? An optimal normalization would give no variation, just one colour, and one neat structure. But this looks nothing of that. A bit of explanation might be in its place: the walls of the figure show coronal (left), sagittal (right) and axial (bottom) slices; the middle part displays the region of interest in 3D

This has a tremendous impact both theoretically and clinically. There is currently a huge interest in this region and whether it is specifically operation in memory (the Squire-Zola model), or whether it has additional roles in visual perception, novelty processing and cross-modal perception (see latest article by Buckley & Gaffan).

Think of it: if you go through all papers reporting hippocampal activation in an fMRI paradigm, but if you re-do the analysis properly, or look at the individual scans, you see that most of the hippocampal activation is actually perirhinal. I'll never trust a spatially normalized image again.

OK, to some people this is old news, but let's face it: most of us eat the results from group studies raw, without chewing too much about how these images were made, i.e. normalized. Well, now I hope you do.

If you want to read more I have two relevant abstracts:

How genes make up your mind

2006-03-13T14:15:00.000+01:00

I have written a small piece about imaging genetics (IG) in Science & Consciousness Review. IG is IMHO really going to revolutionize cognitive science, hopefully even philosophy of mind. The findings made here point altogether to how tightly coupled the mind is to its physical brain, and how our minds are made by our brains.

Just a small passage from my piece:
"Genes control the development of neurons to make up brains, but they also govern neuronal gene expression during our daily lives. (...) Genes work at every level of the neural process. They are the fundamental building blocks for both the structure and the functioning of the brain. They set the stage for how neurons and functional groups of neurons act in response to different inputs. Genes are therefore fundamental for the way we experience, think and behave."

Im-Gen videos now up

2006-03-07T09:05:00.000+01:00

As I mentioned in this post, the videos from this year's International Imaging Genetics Conference would be just around the corner. Turns out that was a precise prediction. The videos for all speakers are now online. Buy some chips and a cola and put yourself in front of a double-screen projector (one with the video and one with the PDF) and enjoy!

CIMBI alive

2006-03-03T08:36:00.000+01:00

The Center for Integrated Molecular Brain Imaging (CIMBI) is now officially opened. The overall idea behind this massive project is to study cognitive, psychological and biological phenomena with a multi-modal approach, combining data from genotyping, PET scanning and MRI scanning. The main project of CIMBI is to study "the neural bases of personality dimensions that predispose individuals to affective and substance use disorders, with special emphasis on the serotonergic neurotransmitter system". In other words: to study the biological mechanisms behind personality formation. They are currently recruiting (and looking for) the best-qualified personnel for the new available positions.

One part of the CIMBI project involves looking at how genes coding for seretonin affect the seretonin transport function, and furthermore how the function of seretonergic areas of the brain operate depending on the genetic makeup of a subject. In this latter part, I am involved in doing the MRI study, including three fMRI protocols:

Processing of facial affect - how genes affect the processing of facial expression, especially the difference between aversive and neutral faces.
Memory processing in the medial temporal lobe (MTL) - how different parts of the MTL make different contribution to specific phases in memory processing: preparation, encoding, rehearsal and retrieval.
Categorization task - the difference between choosing between high-specificity options (within-category choices, e.g. "donkey or zebra") or low-specificity options (between-category choices, e.g. "living or non-living")

Data will be combined between fMRI (BOLD and perfusion), genotype and seretonine function as measured with PET. In addition we are looking at the relative contribution of changes in volume and form of MTL areas to the overall signal differences found in other modalities.

Imaging Genetics stuff

2006-03-03T08:12:00.000+01:00

The slides of most of the presentation from this year's International Imaging Genetics Conference are now available through their website. I surely hope they'll add the videos soon. There are a few that I'd like to have a second (third...n'th...) look at.

I have a few comments to some of the presentations, and to keep in mind:

Nik Schork presented and discussed ways to visualize the imaging/genetics data (especially the latter. Unfortunately, these slides are still missing from the list
Tom Nichols gave a good talk that to me helped binding the fields of genetics, neuroimaging and statistics a bit more together. Again, these slides are also missing
Bernie Devlin is worth having in mind when thinking critically about the projects done in this field.
Andreas Meyer-Lindenberg gave a really cool talk about his work on Williams-Beuren syndrome, and how genes play a role in the brain in social cognition.
Ahmad Hariri gave an equally neat talk about individual differences in appetitive drive.
Dan Weinberger has this extra way of grabbing his audience's attention and make them forget all about jet lag and coffee thirst. His talk about the lessons from the study of COMT were most interesting.

Admitted, it is far from sufficient to see some slides. You can only get the ghist of what you're missing. So let's hope that the Irvine people will add the videos soon. Stay tuned.

Even more brainy genes --- finale

2006-02-25T19:31:00.000+01:00

As a finale to the two previous posts about brain evolution, let me end by referring to this study by Mekel-Bobrov et al in Science. If you have followed blogs such as John Hawks, Gene expression or The Scientist you have probably heard about this story before.

The study "Ongoing Adaptive Evolution of ASPM, a Brain Size Determinantin Homo sapiens" has the following abstract:

"The gene ASPM (abnormal spindle-like microcephaly associated) is a specific regulator of brain size, and its evolution in the lineage leading to Homo sapiens was driven by strong positive selection. Here, we show that one genetic variant of ASPM in humans arose merely about 5800 years ago and has since swept to high frequency under strong positive selection. These findings, especially the remarkably young age of the positively selected variant, suggest that the human brain is still undergoing rapid adaptive evolution."

So the brain has developed significantly during the past 6000 years or so? That is indeed an interestring finding. So what does the ASPM do? What is it related to? Let me recap a brief survey of Hubmed search for "ASPM and brain".

It is related to microencephaly and seizures (1)
It is also related to cortical malformation (2)
The pathological changes are caused by deficient neurogenesis within the neurogenic epithelium (3)
It has been strongly positively selected since the divergence from our common ancestor to the chimp (4)

The list goes on and on, but these are maybe the most prevalent reports and topics.

But listen: we're back to discussing brain size again, right? As I claimed in my first brain-evo post "brain size" can mean a lot of things. Since the brain does not evolve like an inflating balloon, it would be much more interesting to know what parts of the brain that increase in size. I'll bet a dollar that we find the prefrontal cortex driving much of this evolution, but that should also mean that the PfC-connected areas would increase in size, too.

I'm diving more into this matter now, and immediately find some interesting and critical remarks by other blogs: again, John Hawks and Gene Expression share their view in the most eloquent way. Read and learn, and don't forget to speculate about what that ASPM haplotype world map actually might mean.

References

(1) ASPM mutations identified in patients with primary microcephaly and seizures. Shen J, Eyaid W, Mochida GH, Al-Moayyad F, Bodell A, Woods CG, Walsh CA. J Med Genet. 2005 Sep ; 42(9): 725-9

(2) Cortical malformation and pediatric epilepsy: a molecular genetic approach. Mochida GH. J Child Neurol. 2005 Apr ; 20(4): 300-3

(3) Autosomal recessive primary microcephaly (MCPH): a review of clinical, molecular, and evolutionary findings. Woods CG, Bond J, Enard W Am J Hum Genet. 2005 May ; 76(5): 717-28

(4) Adaptive evolution of ASPM, a major determinant of cerebral cortical size in humans. Evans PD, Anderson JR, Vallender EJ, Gilbert SL, Malcom CM, Dorus S, Lahn BT Hum Mol Genet. 2004 Mar 1; 13(5): 489-94

Dennett-Ruse exchange leaked

2006-02-25T17:47:00.000+01:00

Parts of a private email exchange between philosophers Dan Dennett and Michael Ruse have been published on ID doyen William Dembski's blog. And apparently with the permission on Ruse! Several bloggers have commented on the issues raised by Dennett and Ruse*, but to me the real question is: Why on Earth is Ruse, an avowed Darwinist, forwarding his email to Dembski?

* See:

PZ Myers

Jason Rosenhouse

Chris Mooney

More on continuous brain growth in humans

2006-02-24T08:45:00.000+01:00

While we are thinking about brain evolution, consider this study by Evans et al. in Science. They studied the gene Microencephalin (MCPH), which is known for its severe reduction in brain size coupled with mental retardation. Remarkably, despite this abnormality, there is an overall retention of normal brain structure and a lack of overt abnormalities outside of the nervous system. The MCPH function in healthy humans is less well known, and one can speculate whether it has specific brainy advantages to its carrier. As Evans et al conclude in their article:

“[There] could be several possibilities, including brain size, cognition, personality, motor control, or susceptibility to neurological and/or psychiatric diseases.”

What makes this study interesting is the finding that the MCPH has changed during the past ~37.000 years, and that the spread has been fast. In other words there has been a strong positive selection for this gene, indicating that the brain has continued to evolve even in more recent times. The MCPH is also known to be involved in the evolution of hominids, eventually leading to Homo sapiens. The new finding by Evans et al. demonstrates that this trend has been continuing until more recent times, and is there really any reason to think that the same evolutionary trend has stopped?

So evolutionary psychologists be aware -- don’t ever say that today’s humans minds are the same as that of the stone-age man… Of well, to a large extent, it probably is, but this and other similar reports forcefully tells us that we need to unravel the relative contribution of recent evolutionary trajectories in man. It is also necessary to speculate and study the touchy subject on whether there have been local variations in brain size and function according to the recent brain evolutions that have occurred. After all, evolutionary developments about 40.000 years old indicate that there could be geographical variations in the prevalence of this mutation. I don’t think we’ll see yet another claim of the out-of-Africa pertaining to the past 40.000 years or so.

See also comments by John Hawks and Bob Scheid

Here is the abstract from that article:

Microcephalin, a Gene Regulating Brain Size, Continues to Evolve Adaptively in Humans

Patrick D. Evans in Science, vol. 309, September 2005

The gene Microcephalin (MCPH1) regulates brain size and has evolved under strong positive selection in the human evolutionary lineage. We show that one genetic variant of Microcephalin in modern humans, which arose È37,000 years ago, increased in frequency too rapidly to be compatible with neutral drift. This indicates that it has spread under strong positive selection, although the exact nature of the selection is unknown. The finding that an important brain gene has continued to evolve adaptively in anatomically modern humans suggests the ongoing evolutionary plasticity of the human brain. It also makes Microcephalin an attractive candidate locus for studying the genetics of human variation in brain-related phenotypes.

Brainy chromosome

2006-02-22T11:15:00.000+01:00

The brain changes continually. Not only during development or ageing, but over generations, too. While the common popular notion is that the human brain of today is identical to that of the stone age man, recent studies of the genetics underlying brain development has shown that the human brain has changed significantly over a far shorter time -- only a few thousand years.

A recent study by Nusbaum et al. in Nature (see full PDF) analysing the human chromosome 8 briefly mentions two regions called the major defensin gene cluster and MCPH1. They speculate that these regions have played a significant role in the expanded brain size that can be observed through hominid evolution.

At the end of the article, Nusbaum et al. open up a whole new field of study:

"(...) the majority of the genes in the region of high divergence in distal 8p play important roles in development or signalling in the nervous system. Notably, the extremely large CSMD1 gene, which lies at the peak of divergence and diversity, is widely expressed in brain tissues. High regional mutation rates and positive selection are generally assumed to be distinct, but it is possible that the former may facilitate the latter by increasing the rate of appearance of potentially advantageous single, or interacting, alleles. It is intriguing to speculate whether the accelerated divergence rate of this region has contributed to the rapid expansion and evolution of the primate brain."

In other words, the study of chromosome 8 might open a whole new field of enquiry about what makes the human brain special. Knowing the genomic makeup of our closes evolutionary peers will also make it possible to study the relative contribution of this region to brain size and, not to forget, the underlying role this change has had for cognitive processes. Yes, brain size is interesting, but at our current standard, we need to know more than that. Increasing brain size is normally NOT thought to work like an inflating balloon where all areas increase equally. Rather, the evolution of areas occur within systems of modules or areas, often underlying one or a few cognitive functions.

Unravelling the evolution of language?

2006-02-20T15:00:00.000+01:00

There is now an online-only published paper in PNAS from the Max Planck Institute on the evolution of language. What is surprising is that the researchers have used functional MRI to infer the evolutionary lineage from their results. Basically, what Angela Friederici and her colleagues have done is to compare language processing that is "simple" to processing that is "complex". While simple processing activated left frontal operculum, a phylogenetically older region of the brain, more complex language processing also activated Broca's area, which is thought to be a more recent development specific to humans. in addition, the researchers also studied the white matter connectivity of the two brain regions by using MR tractography. Here, they found that the two regions showed different structural connectivity signatures, further supporting the functional segregation of these two areas.

This makes the researchers conclude:
"Here we report findings pointing toward an evolutionarytrajectory with respect to the computation of sequences, fromprocessing simple probabilities to computing hierarchical structures,with the latter recruiting Broca’s area, a cortical regionthat is phylogenetically younger than the frontal operculum,the brain region dealing with the processing of transitionalprobabilities"

I first found this through the Max Planck Society press release page. Just reflecting briefly on this, I think that despite the study is interesting itself in terms of functional segregation of language processes, I am not convinced about the argument about the phylogeny of the two regions. As we know from research on subcortical structures such as the "limbic system", we cannot divide between the phylogenetic "old" and limbic brain and the "newer" cortical brain. It is today considered total gibberis, because evolution of "higher" areas in the cortical surface has had a dynamic and synergetic co-evolution of cortical and subcortical areas. In similar vein, I suspect that the evolutionary trajectories of the frontal operculum and Broca's area share a lot, and that a clear-cut division between the two areas will prove hard to make.

Neuroeconomics and neuromarketing news

2006-02-19T17:35:00.000+01:00

Every week there seem to be new papers out on some neuroeconomics or neuromarketing related topic. Let me briefly mention three new papers I’ve stumbled over during the last few days.

[1] In the latest issue of Science a group of researchers at University of Amsterdam report two psychological studies testing how we reach a decision as to what product to buy. Here’s a short description of the first test from Greg Miller’s accompanying news piece:

To test the idea, Dijksterhuis and colleagues asked volunteers to read brief descriptions of four hypothetical cars and pick the one they'd like to buy after mulling it over for 4 minutes. The researchers made the decision far simpler than it is in real life by limiting the descriptions to just four attributes such as good gas mileage or poor legroom. One of the cars had more plusses than the others, and most participants chose this car. But when the researchers made the decision more complex by listing 12 attributes for each car, people identified the best car only about 25% of the time--no better than chance. The real surprise came when the researchers distracted the participants with anagram puzzles for 4 minutes before asking for their choices. More than half picked the best car. The counterintuitive conclusion, Dijksterhuis says, is that complex decisions are best made without conscious attention to the problem at hand.

They then left the laboratory to further test this result in a more ecological setting:

To test the idea in a more natural setting, the researchers visited two stores: the international furniture store IKEA and a department store called Bijenkorf. A pilot study with volunteer subjects had suggested that shoppers weigh more attributes when buying furniture than when buying kitchen accessories and other simple products commonly purchased at Bijenkorf. The researchers quizzed shoppers at the two stores about how much time they'd spent thinking about their purchases and then called them a few weeks later to gauge their satisfaction. Bijenkorf shoppers who spent more time consciously deliberating their choices were more pleased with their purchases--evidence that conscious thought is good for simple decisions, Dijksterhuis says. But at IKEA, the reverse was true: Those who reported spending less time deliberating turned out to be the happiest.

Of course, these results square well with a host of other recent neuroeconomic experiments which have found that decision-making is not only a matter of pain-staking cognitive deliberations, but also involves automatic and unconscious emotional biases. Yet, I’m beginning to wonder if we are not now in a position where we need more experimental attention to the interplay of emotions and cognition.

[2] In forthcoming issue of NeuroImage there will appear a new neuromarketing study by a German team that suggest that brand knowledge is computed by parts of the prefrontal cortex. Here’s the abstract:

Brands have a high impact on people's economic decisions. People may prefer products of brands even among almost identical products. Brands can be defined as cultural-based symbols, which promise certain advantages of a product. Recent studies suggest that the prefrontal cortex may be crucial for the processing of brand knowledge. The aim of this study was to examine the neural correlates of culturally based brands. We confronted subjects with logos of car manufactures during an fMRI session and instructed them to imagine and use a car of these companies. As a control condition, we used graphically comparable logos of car manufacturers that were unfamiliar to the culture of the subjects participating in this study. If they did not know the logo of the brand, they were told to imagine and use a generic car. Results showed activation of a single region in the medial prefrontal cortex related to the logos of the culturally familiar brands. We discuss the results as self-relevant processing induced by the imagined use of cars of familiar brands and suggest that the prefrontal cortex plays a crucial role for processing culturally based brands.

Again, if you have paid attention to the now rather huge literature on preferences, you will not be overly surprised by this result, although we may wonder why the Neuron brand study I mentioned last week found activation in lateral parts of the PFC, and this study activation in the medial parts. Two things, however. (1) First, a lot of studies are pointing to the medial OFC, or orbitofrontal cortex, as the locus of utility tracking, or the seat of the brain’s overall preference system. But what is this section of the brain actually doing. (2) What does the brain’s preference system more precisely have to do with brands? Is “a brand” just certain emotional response to some product or person? If so, how are such emotional preferences build?

[3] Finally, let me point you to a new review of the current status of the field of neuroeconomics which are set to appear in the next issue of Trends in Cognitive Science. The in press version can be found here. The authors are Alan Sanfey, George Loewenstein, Samuel McClure and Jon Cohen, four of the leaders of the field.

References

Dijksterhuis, A. et al. (2006): On Making the Right Choice: The Deliberation-Without-Attention Effect. Science 311: 1005-1007.

Schaefer, M. et al. (In press): Neural correlates of culturally familiar brands of car manufacturers. NeuroImage, to appear.

Sanfey, A. et al. (In press): Neuroeconomics: cross-currents in research on decision-making. Trends in Cognitive Science, to appear.

Incidental findings in fMRI

2006-02-14T23:39:00.000+01:00

Judy Illes, director of the Program in Neuroethics at the Stanford Center for Biomedical Ethics, has a new paper out in last Friday's Science. Co-written with a large number of researchers, working with brain imaging techniques, the paper highlights the ethical issues raised by incidental findings in such studies. The basic problem is that, although a subject may appear healthy, and feel healthy, structural MRI's and other types of imaging data may yet divulge unexpected brain abnormalities. It is something all non-clinical experiments from time to time are certain to experience - I have myself - and we therefore need a policy for dealing with such findings, especially since many PET and fMRI experiments these days are conducted by investigators who are not medically trained.

Also, we should bear in mind that what today is solely a question of incidental clinical findings may in the future expand to many other, non-clinical areas. You volunteer to partcipate in a language study, and your scanning data turn out to indicate that you have paedophelic tendencies. Should this finding be reported or not?

Reference

Illes, J. et al. (2006): Incidental findings in brain imaging research. Science 311: 783-784.

Neuromarketing

2006-02-13T20:59:00.000+01:00

For some years now the marketing industry has been intrigued by the possiblity of using brain science to get a handle on people's secret desires. Using brain scanners, the hope is to perfect the marketing of products by learning which presentations trigger the brain's "cool" or "must buy" buttons. The always great magazine Wired ran a story in its October 2004 issue on the neuromarketing research by Steven Quartz with the superb title "If you secretly like Michael Bolton, we'll know". (Quartz, by the way, is rumored to have a book out this year explaining "the neurobiology of cool".) Still, personally I only know of one real neuromarketing study, namely the well-known Neuron-study conducted by the Montague group which investigated how knowing the brand of two different cola products influences their consumption. (Quartz is one of the co-authors of this study, but hasn't published anything else on the subject in peer-refereed journals.)

Now, in connection with the American super bowl, Marco Iacoboni has conducted an "instant-science experiment" where he and his colleagues imaged 5 subjects in an fMRI scanner while they watched the ads run during the breaks in the game. He then published a preliminary report on the www.edge.org website which has prompted a slush of comments. The New York Times referenced Iacobon's short article, and a number of bloggers have made their thoughts public in the days since. See for instance the Neuromarketing blog's positive reaction here, and then compared it to the Mind Hack guys' much more negative reaction here.

For my own money, I find the general idea of investigating the neural machinery that make us react in one way or another to ads and products both highly interesting and very important. (It is an important aspect of out lifes.) I don't feel, however, that any neuromarketing experiment at the moment will be able to tell an ad agency anything really important. Our knowledge of how the brain's preference system works is simply to rudimentary. The way Iacoboni claims he can see activity in his subjects' brains which are at odds with their overt reports must be treated with the utmost skepsis. Even if some ad actually elicits a high response in the reward system this activity may not, simply, correlate with a clear-cut preference for the ad. The reason is that the reward system is composed of several different structures which may interact and compete for the final verdict. (This is something I myself often see in my own research on aesthetic preferences for works of art.) Iacoboni, an expert of mirror neurons, also speculates that one ad, which very strongly activated the premotor region, might be the most "succesful" ad. But how does he know that the mirror neurons located in this region even play an important role in the formation of preferences? This is certainly news to me. It may well be true, as he writes, that mirror neurons activity underlies some sort of empathy with the persons depincted in the perceived ads, but I have never seen any experimental evidence linking empathy to preference. We might well prefer persons we empathize with, but nobody has, as of yet, demonstrated that we do so, to my knowledge at least.

As important as this research is in principle, we should be careful not to get over-excited about single studies that claim a lot. Especially if they are based on group analyses involving data from only 5 subjects! We should go forward with research on neuromarketing, but at the same time remember that there is a long way to go.

Brainy politicians

2006-02-09T11:04:00.000+01:00

Here's a new field of scientific enquiry: Political Biology, or biopolitics. It sounds strange, doesn't it? To me, it sounds most like politicians trying to influence how research should be conducted, which areas should be allowable and which should not.

But it's actually the reverse: as this page attests, biopolitics is about how politics could and should be influenced by scientific advances in biology (and, as a consequence, neuroscience). My only - yet substantial - concern is that this approach seems to stop at "biology", especially evolutionary theory. It most likely includes evolutionary psychology, but even within EP, we rarely if ever see proper discussions about how brain science can inform psychological theories. As this previous note from Martin shows, neuroscience CAN indeed say meaningful things to cognitive and evolutionary psychological theory. So the concern with biopolitics is that it will not include the full range of scientific results in this rapidly developing field.

From that very site, it says;

In their classic formulations, valid to this day, the issue of self-preservation is foundational for both political science and economics. In order to fixate this concept, the Modern theorists relied upon various assumptions about human nature. Due to the advances of biology and evolutionary theory, we are today in the position of explicating these assumptions in the form of stable scientific certainties. A foundational concept in biological theory is that of "fitness". The paper indicates the relationship between the less determined concept of self-preservation and the more rigorous one of fitness. By that, it accomplishes two things: it gives more solidity to the foundation of political theory and political economy, by anchoring them in biology; it opens the path towards a unification between two social sciences and their immediate juxtaposed science, biology. The emphasis of the paper is on political science, aiming to define, on the basis of the above argument, its proper object of study. The notion of fitness extraction is thus defined. A lateral exposition differentiates between political action, thus understood, and economic action, defined more generally as fitness transfer. The distinction is to be eventually furthered in a separate study.

Nalmafene for your ludomania

2006-02-09T10:55:00.000+01:00

I have mentioned this as a headline at SCR. A new study demonstrates that Nalmefene, an experimental drug, has positive treatment effects on compulsive gambling. It works through making gambling become less thrilling and compelling. Maybe we can soon find a drug that makes statistics lectures more exciting, too?

__________________________________________

Multicenter investigation of the opioid antagonist nalmefene in the treatment of pathological gambling.

by Grant et al. in Am J Psychiatry. 2006 Feb ; 163(2): 303-12

OBJECTIVE: Pathological gambling is a disabling disorder experienced by approximately 1%-2% of adults and for which there are few empirically validated treatments. The authors examined the efficacy and tolerability of the opioid antagonist nalmefene in the treatment of adults with pathological gambling.

METHOD: A 16-week, randomized, dose-ranging, double-blind, placebo-controlled trial was conducted at 15 outpatient treatment centers across the United States between March 2002 and April 2003. Two hundred seven persons with DSM-IV pathological gambling were randomly assigned to receive nalmefene (25 mg/day, 50 mg/day, or 100 mg/day) or placebo. Scores on the primary outcome measure (Yale-Brown Obsessive Compulsive Scale Modified for Pathological Gambling) were analyzed by using a linear mixed-effects model.

RESULTS: Estimated regression coefficients showed that the 25 mg/day and 50 mg/day nalmefene groups had significantly different scores on the Yale-Brown Obsessive Compulsive Scale Modified for Pathological Gambling, compared to the placebo group. A total of 59.2% of the subjects who received 25 mg/day of nalmefene were rated as "much improved" or "very much improved" at the last evaluation, compared to 34.0% of those who received placebo. Adverse experiences included nausea, dizziness, and insomnia.

CONCLUSIONS: Subjects who received nalmefene had a statistically significant reduction in severity of pathological gambling. Low-dose nalmefene (25 mg/day) appeared efficacious and was associated with few adverse events. Higher doses (50 mg/day and 100 mg/day) resulted in intolerable side effects.

HubMed (cache)

______________________________________

Drug Shows Promise in Curbing Compulsive Gambling, Study Says

By Robert Lee Hotz in The Nation

For the estimated 6 million compulsive gamblers in the U.S., the long odds are on a pill.

In the largest clinical study of its kind, researchers at the University of Minnesota found that daily doses of an experimental drug called nalmefene, often used to treat alcoholism, appeared to curb the craving to gamble.

The research represents the latest effort to control the biology of misbehavior at a time when celebrity poker, online gambling, lotteries and sports betting have helped to make obsessive wagering a national psychiatric disorder.

"The study is part of emerging evidence that gambling, once thought to be a problem in moral integrity, is instead a problem in brain biology and can be successfully treated," said Dr. Robert Freedman, editor of the American Journal of Psychiatry, which published the study today in its February issue.

(...)

The Nation

Self and personality stability in ageing

2006-02-07T09:39:00.000+01:00

A recent meta-analysis by Roberts, Walton and Viechtbauer published in Psychological Bulletin demonstrate that personality traits change over time. Some things that change over time includes our social interactions, they find, as well as our emotional stability. It would be most interesting to see how these findings relate to our normal sense of self, i.e. our feeling that we are the same person over time.

Here is the abstract:

Patterns of mean-level change in personality traits across the life course: a meta-analysis of longitudinal studies.

Roberts BW, Walton KE, Viechtbauer W in Psychol Bull. 2006 Jan ; 132(1): 1-25

The present study used meta-analytic techniques (number of samples = 92) to determine the patterns of mean-level change in personality traits across the life course. Results showed that people increase in measures of social dominance (a facet of extraversion), conscientiousness, and emotional stability, especially in young adulthood (age 20 to 40). In contrast, people increase on measures of social vitality (a 2nd facet of extraversion) and openness in adolescence but then decrease in both of these domains in old age. Agreeableness changed only in old age. Of the 6 trait categories, 4 demonstrated significant change in middle and old age. Gender and attrition had minimal effects on change, whereas longer studies and studies based on younger cohorts showed greater change. ((c) 2006 APA, all rights reserved).

HubMed

Brent Robert homepage

Mind Wars!

2006-02-06T13:52:00.000+01:00

In the wake of my post yesterday about US government attempts to build a workable lie detector for use in the war on terror, here is an article about Jonathan Moreno, bioethics adviser for the Howard Hughes Medical Institute, who has a book coming out later this year entitled Mind Wars: National Security and the Brain. A little teaser from the article:

One of the leaders in neuroscience development is the corporation DARPA, which is currently in the process of developing a "head web," a helmet that conducts non-invasive brain monitoring that could be used to measure brain waves while soldiers are in combat. Moreno said the government is also working on developing a "war fighter"-a human manipulated by drugs to be a more efficient soldier. The "war fighter" would require less sleep, less protein and could heal itself with the aid of drugs and technology. The war fighters would eventually be replaced by robots, which would be controlled by human soldiers in a bunker somewhere out of harm's way. "We are probably moving to a cyborg technology," Moreno said, and one of the first steps toward a more robotic world is the use of neurologically manipulative drugs, like the "anti-conscience pill," which can treat stress, reduce guilt and potentially eliminate entire memories, preventing psychological conditions like post-traumatic stress disorder.

Says Moreno:

"I don't think the government will control our brains in the old-fashioned, 'Manchurian Candidate' sense, but we will eventually be able to change our brains."

I found the link to the article at the excellent Neuromarketing Blog.

Imaging Genetics 2006

2006-02-06T09:08:00.000+01:00

It has taken me some time to digest the impressions from the 1½ day International Imaging Genetics conference held in Irvine a couple of weeks ago. This is probably because it was hard to sort the different issues out initially. The conference had speakers from genetics, statistics and neuroimaging.

Correspondingly, there were three major Imaging Genetics (IG) themes one can sort this conference into: genetics methods, statistical approaches and visualisations, and neuroimaging related issues.

IG Statistics
Doing statistics is a humbling experience, and the IG conference was a wonderful reminder of this. In the burgeoning field of IG, many studies that have been published in top rated journals would probably not even make it past the editor today. On the other hand, it's only been a few years since one could get an article published in Nature or Science because you found some signal in the brain during a cognitive task. Anyway, the statistics were no exception to all the demonstrations associated with doing statistics, although it came with a twist. Since IG is a combination of at least two approaches - genetics and neuroimaging - each study must seek to accommodate to the pitfalls and premises of both approaches. This is not a simple task: neuroimaging contains a multitude of different statistical approaches, in addition to an overwhelming number of issues and pitfalls when it comes to the design, collection and preparation (i.e. preprocessing) stages in a study. I can only guess that the same goes for genetics.

During lunch, I heard a geneticist asking "What is a voxel? Is it like a pixel?". So IG has a long way to go in order to reach a full, common understanding and sharing of ideas, concepts and methods. I'm certainly asking just the same kind of beginner's questions about genetics. So when Bernie Devlin said about the speaker before him, Tom Nichols, "I am glad that Tom says he does not know much about genetics. I can assure you - he doesn't!" he was making this very point.

But the IG statistics also had some very interesting and directly useful aspects. Nik Schork talked about different ways to visualise and analyse IG data, and demonstrated a most impressive toolbox of different methods for doing so. Unfortunately, I can't find any illustrations online (nor in any article) to show this. I'll get back with as soon as something comes up. See also this video of one of his talks.

Genetics
This part was probably the hardest, since so much relied on one's knowledge about genetics. Haplotype, SNPs, alleles and so on, just to mention a few. If you have not heard about this before, you're not alone. But even knowing about these keywords and concepts, bringing them together with neuroimaging really poses a test of your working memory ability... I'll expose my lack of understanding of these issues here,yet still mention the hapmap project and its tremendous usefulness in assessing the distribution of haplotypes in different populations. Not directly viable when doing neuroimaging studies, but it can influence the likelihood that you choose to study one haplotype rather than others.

Neuroimaging
This is by far the easiest part of the conference, at least to me, and I guess geneticists had the harder time in this part of the conference. However, one can also see that the neuroimaging studies that were presented here really demonstrated the end results of the tedious work that had been presented in the foregoing talks. Since neither the basics of neuroimaging signals, stats or pitfalls were presented as such, researchers from other - non-neuroimaging - approaches probably had an easier time than us genetics-nogoods had previously...

Basically, one could say that IG brings a new tool to look at what drives your neuroimaging data, even in healthy individuals. Studies by researchers as Ahmad Hariri, Dan Wainberger and Andreas Meyer-Lindenberg illustrates this point clearly. Their studies have now demonstrated that a natural variation in specific alleles produce different responses in not only the brains of the different subjects, but even how behaviour is affected. This includes a study of how long and short versions of a seretonin transporter gene affects brain regions affected in depression. It can also demonstrate how genes affect the brain to produce a higher risk of developing schizophrenia, or how a gene influences brain size. It can also be used to enhance our understanding of different cognitive functions, such as attentional networks, in the brain.

For last year's conference you can now download video recordings and the slideshows of the talks from the Irvine IG conference homepage. I suspect that the talks for this year will be available soon, too.

Mixing Teeth of the Memory Mind

2006-02-06T09:06:00.000+01:00

Just found this interesting blog called Mixing Memory. From the blog you can read:

The Intellectual Teeth of the Mind

Early one morning earlier this week, I received an email about a radio program in Massachusets called Radio Open Source, which aired a program that evening on TheEdge.org's question, "What is your dangerous idea?" (I believe you can listen to the program at any time by following that link). I'm sure some of you who commented on the question received an email as well (Razib was even quoted on the show). The email mentioned that they were going to be interviewing Steven Pinker and others. So while I was sitting around doing some work, I listened to the program. It was actually pretty interesting. The "others" included Jesse Bering, Daniel Dennett, and Steven Strogatz. I'll try to get to Berring's answer, and his work (which is interesting as well) in a future post, but for now, I want to concentrate on something that the answers given by Dennett and Strogatz reminded me of. If you recall, Dennett's answer to TheEdge.org's question was about memes (big surprise). He said, in essence, that our minds are being inundated with memes, and pretty soon, if it isn't the case already, there will be more memes than we can handle. Strogatz' answer is related, though in a non-obvious way, perhaps.

The neuroscience of lying

2006-02-05T15:47:00.001+01:00

Lying seems to be the topic of the day. In the last month alone two popular articles have appeared covering recent attempts to unveil the brain signatures of lying. The first came out in the January issue of Wired. (You may find the electronic version here.) And today the NY Times Magazine follow up with their take on the story. Go read it here.

Both articles basically report the same story. Aftet 9/11 the American government has become highly interested in procuring a sure-fire method of spotting liers. The American military has a whole department, the Department of Defense Polygraph Institute (DODpi), working exclusively on inventing an easy-to-use device that in the future will be able to tell apart lies from the truth. Clearly such a device will have to be based on the ability to identify physical tell-tale signs that a person is lying. And to do so, DODpi will have to know the neural cause of lying. Reportedly more than 50 American labs are currently working on identifying these brain processes.

Not much, however, is known about the neurocognitive mechanisms underlying lying. Chances are that lying cannot be associated with just one "lie-module". When lying you must be able to distinguish the lie from the truth; you will probably have to activate your ToM-system in order to organize your lie in accordance with what you think the other person knows and wants to hear; in some situations you have to remember what you have previously told other persons; you certainly have to plan ahead; and most probably you will have to control your emotional system. These cognitive mechanisms all rely on numerous neural processes.

So, what to do about structures that show up on statistical parametric maps in fMRI experiments? Dan Langleben - the first researcher to study lying with fMRI - have demonstrated that making a lie is associated with elevated activity in the anterior cingulate cortex. Yet, as I have previously noted in a post on this blog, the precise function of the ACC is still unclear. Thus, it may be the case that even though lying is associated with ACC activity, not all activity in the ACC is associated with lying! This opacity of the brain raises serious ethical questions, because will a DODpi-device made to detect ACC activity label some people liars who are not really lying? And will it, coversely, neglect liars who are lying using other neurocognitive mechanisms than just the ACC? These questions pose a serious challenge to the race for a neuroscience-based lie detector.

Another, more profound, ethical questions that this reserach raises is the following: do we really want to live in world without lying? Generally, lying is frowned upon. Yet, imagine if you had to tell the truth all the time. It is not only lawyers, such as the character Jim Carey plays in Liar Liar, that benefit from our ability to conceil our innermost thoughts and deceive. Lying plays an enormous role in human social life, some for bad, but some also for good. If lie detection devices should become succesful we will have to discuss when and where to use them. In the class room, at a job interview, in the minister's office when we get married?

References

Langleben, D. et al. (2002): Brain activity during simulated deception: An event-related functional magnetic resonance study (PDF file). Neuroimage 15: 727-732.

Silberman, S. (2006): Don't even think about lying. Wired 14.01.

Henig, R.M. (2006): Looking for the lie. New York Times Magazine. February 5, 2006.

Sex and Money: Neurofinance

2006-02-04T21:09:00.000+01:00

One of the most exiting new fields of neuroscience is neuroeconomics. As the name indicate, this field investigates the decision-making processes that underlie economic behaviour. As was to be expected neuroeconomics is now spawning a off-spring called neurofinance. Why are some investors better at making money than others? The first neurofinance study, using brain imaging, was published in the September 1 issue of Neuron. Here's the authors abstract:

Investors systematically deviate from rationality when making financial decisions, yet the mechanisms responsible for these deviations have not been identified. Using event-related fMRI, we examined whether anticipatory neural activity would predict optimal and suboptimal choices in a financial decision-making task. We characterized two types of deviations from the optimal investment strategy of a rational risk-neutral agent as risk-seeking mistakes and risk-aversion mistakes. Nucleus accumbens activation preceded risky choices as well as risk-seeking mistakes, while anterior insula activation preceded riskless choices as well as risk-aversion mistakes. These findings suggest that distinct neural circuits linked to anticipatory affect promote different types of financial choices and indicate that excessive activation of these circuits may lead to investing mistakes. Thus, consideration of anticipatory neural mechanisms may add predictive power to the rational actor model of economic decision making.

If you wish to prepare yourself for the reading of Camelia Kuhnen and Brian Knutson's paper go to Bloomberg.com here where you will find a nice journalistic take on the whole neurofinance phenomenon. It can more or less be summed up in the statement from Daniel Kahneman, quoted in the article:

"The brain scientists are the wave of the future in the financial world".

Indeed!

References

Kuhnen, C. & Knutson, B. (2005): The neural basis of financial risk taking. Neuron 47: 763-770.

Levy, A. (2006): Brain scans show link between lust for sex and money. Bloomberg.com. February 1.

Improving law through neuroscience

2006-01-30T15:15:00.000+01:00

The insights from brain science has the potential to alter the making and practice of law. But how and why? What is so special about brain science that gives it this potent source of change?

Let's reverse that question by asking: what is so good about our current models about human thought, motivation and behaviour that makes us certain that our laws reflect the most correct view of human behaviour? I thought so; I don't feel the slightest confident that our current models of the mind are merely good enough (by our scientific standards).

Luckily, our models are improving -- from day to day, some would say. It's definitely not a linear progress, IOW that each new publication makes an added improvement to our understanding. The battle of theories are still dominating the field, so whether you choose to go with Damasio or Rolls on the issue of decision making, it will have an influence on the laws you make. But whatever use we make of such models, be it law systems, educational practices or child rearing, we should use the most up to date and most supported models.

This is suggested in a thorough and comprehensive (and very long) article by Owen Jones and Timothy Goldsmith. Jones and Goldsmith argue that better understanding of the biology of behaviour makes better laws. I won't brag with reading the entire document, but I will do. If I stumble across anything especially important (which is likely) I'll drop a note.

------------------------------------------
Here is the abstract. Get the full article here (PDF).
See also a story in Medical News Today

LAW AND BEHAVIORAL BIOLOGY
Owen D. Jones & Timothy H. Goldsmith

Society uses law to encourage people to behave differently than they would behave in the absence of law. This fundamental purpose makes law highly dependent on sound understandings of the multiple causes of human behavior. The better those understandings, the better law can achieve social goals with legal tools.

In this Article, Professors Jones and Goldsmith argue that many long-held understandings about where behavior comes from are rapidly obsolescing as a consequence of developments in the various fields constituting behavioral biology. By helping to refine law’s understandings of behavior’s causes, they argue, behavioral biology can help to improve law’s effectiveness and efficiency.

Part I examines how and why law and behavioral biology are connected.
Part II provides an introduction to key concepts in behavioral biology.
Part III identifies, explores, and illustrates a wide variety of contexts in which behavioral biology can be useful to law.
Part IV addresses concerns that sometimes arise when considering biological influences on human behavior.

More on neuroprosthetics

2006-01-28T19:32:00.000+01:00

If you downloaded the radio programme on neuroprosthetics that Thomas mentions in a post below, you'll want to also hear the January 13 version of BBC's excellent radio show Science Frontier. Here's the presentation of the programme, to be found at Radio 4's web-site:

People with nerve or limb injuries may one day be able to command wheelchairs, prosthetics and even paralysed arms and legs by "thinking them through" the motions.

As researchers overcome the technical and biological hurdles to begin the first human trials, Peter Evans examines how capturing brain output could allow fully paralysed patients to interact with the world.

The idea behind the research is to insert a computer between pathways in the brain and the world outside, which have been broken due to neurological injuries or diseases.

At Duke University's Center for Neuroengineering in North Carolina, Professor Miguel Nicolelis has created an artificial bypass to carry brain signals to an activator, which produces the movement the person is thinking about.

Thanks to a tiny implant in the motor cortex, monkeys have been able to control a robotic arm, just by thinking about making the movement.

Researchers at Brown University in Rhode Island have taken things a step further by working with a tetraplegic man.

They have found that the patient's motor cortex still transmits the same electrical signals a non-paralysed person uses to control their muscles, even though the connections themselves are broken.

The research team has captured these signals using microelectrodes, and built the technology to allow him to carry out basic tasks by moving a cursor around a computer screen.

For the patient, carrying out these simple activities represents a significant improvement in the quality of his life.

You can find a stream of the programme here.

Meeting of Minds report out

2006-01-27T18:12:00.000+01:00

Throughout 2005 126 EU citizens participated in something called the "Meeting of Minds", learning about neuroscience and debating what to do with our ever increasing knowledge about the brain. Here is how the project is described on its web-page www.meetingmindseurope.org:

Meeting of Minds. European Citizens’ Deliberation on Brain Science is a two-year pilot project led by a European panel of 126 citizens. A partner consortium of technology assessment bodies, science museums, academic institutions and public foundations from nine European countries launched this initiative in 2004 with the support of the European Commission.

The initiative will give European citizens a unique opportunity to learn more about the impact of brain research on their daily lives and society as a whole, to discuss their questions and ideas with leading European researchers, experts and policy-makers, put them in touch with fellow citizens from other European countries and make a personal contribution to a report detailing what the people of Europe believe to be possible and desirable in the area of brain science and what they recommend policy-makers and researchers to be aware of for future developments in this field.

Through this approach, the Meeting of Minds initiative wishes to meet EU calls for greater public involvement in the debate on future research, technological decision-making and governance.

The results of their deliberation is now out in the form of a report which can be downloaded here. The 126, now neuro-wize, citizens recommend 36 policy initiatives concerning the practical use of our knowledge about the brain. The majority of these suggestions are pretty dissapointing, merely reflecting various general medical concerns. They do, however, raise two brain-specific issues. (1) First, they suggest that it should be illegal for police, courts, and other official institutions, to use brain scans as information about citizens. (2) Second, they argue for a more public discussion as to what exactly constitutes normal behaviour, and what counts as a mental decease. Both excellent problems that we will certainly return to her at Brainethics in coming posts.

But why, oh why, hasn't this report received more press, at least in the European media?

More compassionate through meditation?

2006-01-25T13:52:00.000+01:00

Apparently the Dalai Lama is a science buff. For some years now he has lend out munks to Richard Davidson, an expert on emotion, who is currently studying what happens when these monks meditate. In 2004 Davidson and his colleagues published a paper in PNAS showing a difference in neural activity in buddhist monks compared to a control group when measured with EEG. Personally, I don't see this as very surprising. Tons of evidence is pointing to the fact that ekspertise in some field correlate with some change to the brain. The big question is: Exactly what kind of change are we talking about? More neurons, different connections, an elevated influx of neurotransmitters, or something else? Unfortunately, EEG can't tell us anything about what is different about the monks' brains. Also, registrering a difference in brain activity doesn't tell us much about putative functional differences. Buddhists claim that they have been able to evolve a more compasionate attittude towards other people through their meditating. Maybe. But it is surely somewhat premature to conclude that meditation actually have such power to make us all more compassionate. Although, of course, it may turn out to be true.

On it's website Wired has a story about the relation between the Lama and Davidson. It also reports on the furore surrounding the Dalai Lama's visit to the Society for Neuroscience conference in November. Get it here.

References

Geirland, J. (2006): Buddha on the Brain. Wired. Issue 14.02.

Lutz, A. et al. (2004). Long-term meditators self-induce high-amplitude synchrony during mental practice. Proceedings of the National Academy of Sciences, 101, 16369-16373.

Ekman, P., Davidson, R.J., Ricard, M. & Wallace, B. Alan. Buddhist and psychological perspectives on emotions and well-Being. Current Directions in Psychological Science, 14, 59-63.

Fusiform -- not alone

2006-01-24T21:24:00.000+01:00

One of the important basic discussions in congitive neuroscience is that of the fusiform face area (FFA). The FFA has been suggested as a part of the fusiform gyrus that is solely dedicated to face perception. The rationale is that faces have been evolutionary special and selected for, and that the FFA is an evolved module specifically dealing with faces.

As the story goes, researchers such as Isabel Gauthier and her colleagues have demonstrated that the FFA is also active when study participants are asked to discriminate between different types of birds and cars and even when participants become expert at distinguishing computer generated nonsense shapes known as greebles. These activations were not as profound as those seen when subjects perceived faces, but they still demonstrate a less clear-cut role of the FFA. At the Human Brain Mapping 2005 in Toronto , Canada, we saw Gauthier and Nancy Kanwisher battle it out, and it is clear that this is by no means a settled issue. The selectivity and encapsulation of neuro-cognitive modules is one of the hot topics in modern cognitive neuroscience, though even in its infancy it was a much debated issue. Just take John Hughlings Jackson's (1882/1932) famous and excellent quote:

"I am neither a universalizer nor a localizer...In consequence I have been attacked as a universalizer and also as a localizer. But I do not remember that the view I really hold as to localization has ever been referred to. If it is, it will very likely be supposed to be a fusion of, or a compromise of recent doctrines"

In a recent study reported in Neuropsychologia by Steeves et al., the FFA does not seem to be sufficient to produce face recognition. Well, that does not come as such a surprise maybe, since we do know that face perception is the result of processes starting in the retina. But the whole idea is that the FFA is something special for face processing. But Steeves et al.s study show that the FFA is part of a larger network, and that face processing consists of many different steps and subprocesses. Their patient study of D.F., combined with fMRI studies demonstrate that

For gross detection of face-nonface decitions, the FFA does not seem necessary although it can be activated. For this, the occipital face area (OFA) seems to do the work.
For face identification -- i.e. recognising a familiar face -- the FFA is involved, but still involves a network of different modules (including the OFA)

In short, Oma und Opa get your OFA going, too. Here is the article's abstract, but you can get the article here (PDF):

The fusiform face area is not sufficient for face recognition: Evidence from a patient with dense prosopagnosia and no occipital face area

Steeves et al.

We tested functional activation for faces in patient D.F., who following acquired brain damage has a profound deficit in object recognition based on form (visual form agnosia) and also prosopagnosia that is undocumented to date. Functional imaging demonstrated that like our control observers, D.F. shows significantly more activation when passively viewing face compared to scene images in an area that is consistent with the fusiform face area (FFA) (p < 0.01). Control observers also show occipital face area (OFA) activation; however, whereas D.F.'s lesions appear to overlap the OFA bilaterally.

We asked, given that D.F. shows FFA activation for faces, to what extent is she able to recognize faces? D.F. demonstrated a severe impairment in higher level face processing—she could not recognize face identity, gender or emotional expression. In contrast, she performed relatively normally on many face categorization tasks. D.F. can differentiate faces from non-faces given sufficient texture information and processing time, and she can do this is independent of color and illumination information. D.F. can use configural information for categorizing faces when they are presented in an upright but not a sideways orientation and given that she also cannot discriminate half-faces she may rely on a spatially symmetric feature arrangement.

Faces appear to be a unique category, which she can classify even when she has no advance knowledge that she will be shown face images. Together, these imaging and behavioral data support the importance of the integrity of a complex network of regions for face identification, including more than just the FFA—in particular the OFA, a region believed to be associated with low-level processing.

Reward processing and extrovert behaviour

2006-01-23T13:14:00.000+01:00

Yesterday I mentioned that brain scientists are actively investigating the neural processes underlying personality differences in behaviour. A very nice example of this research is to be found in the latest issue of Cognitive Brain Research. Michael Cohen and his colleagues linked personality testing, fMRI and genetic analysis to look into how personality may correlate with different neurocognitive ways of handling an economic game. Here is the abstract:

Psychologists have linked the personality trait extraversion both to differences in reward sensitivity and to dopamine functioning, but little is known about how these differences are reflected in the functioning of the brain's dopaminergic neural reward system. Here, we show that individual differences in extraversion and the presence of the A1 allele on the dopamine D2 receptor gene predict activation magnitudes in the brain's reward system during a gambling task. In two functional MRI experiments, participants probabilistically received rewards either immediately following a behavioral response (Study 1) or after a 7.5 s anticipation period (Study 2). Although group activation maps revealed anticipation- and reward-related activations in the reward system, individual differences in extraversion and the presence of the D2 Taq1A allele predicted a significant amount of inter-subject variability in the magnitudes of reward-related, but not anticipation-related, activations. These results demonstrate a link between stable differences in personality, genetics, and brain functioning.

Note how juxtaposing the various types of data effectively unveil insights into brain activity we would have no possibility of gaining using just one method. Combining behavioural, imaging, and genetic data, will probably soon become the gold standard of cognitive neuroscience.

Reference

Cohen, M. et al. (2005): Individual differences in extroversion and dopamine genetics predict neural reward responses. Cognitive Brain Research 25: 851-861.

Animal personality

2006-01-22T12:27:00.000+01:00

Today's NY Times Magazine has a rather fascinating story about research on animal personality. Although eradicated by behaviourism, the notion that others animals than ourselves display various personality types - timid, bold, aggresive, etc. - is becoming increasingly accepted in the worlds of biology and psychology. Researchers such as Sam Gosling - visit his site for in-depth research papers on the topic - are pondering why personalities exist at all; why aren't the behavioural profile of the members of an species just uniform and similar? The answer may be that it is advantageous to have a repertoire of behavioral traits around if the milieu of a species should change. In some niches bold members will have a survival edge, in others cautious members will be better of.

Unfortunately, the article doesn't go into the issue of what brain processes underlie personality traits. This kind of research is also booming, though. So, perhaps we may hope to see a follow-up article on this topic as well.

Reference

Siebert, C. (2006): The Animal Self. New York Times Magazine, January 22 issue.

Critical remarks about art in the brain

2006-01-19T22:39:00.000+01:00

An online published paper by John Hyman provides a thorough criticism of two major contributors to the emergent field of neuroaesthetics, V.S. Ramachandran and Semir Zeki.

Art and Neuroscience

From the article:

I want to discuss a new area of scientific research called neuro-aesthetics, which is the study of art by neuroscientists. The most prominent champions of neuro-aesthetics are V.S. Ramachandran and Semir Zeki (fig. 1). They have both made ambitious claims about their work. Ramachandran says boldly that he has discovered ‘the key to understanding what art really is’, and that his theory of art can be tested by brain imaging experiments, although he is vague about the experimental design. And Zeki, who originally coined the term ‘neuro-aesthetics’, claims to have laid the foundations for understanding ‘the biological basis of aesthetic experience’

(...)

The main defect in the work I have discussed is that both authors propose extravagant generalizations about art – all art is caricature; all great art is ambiguous – and then discuss a small number of examples, which are chosen to illustrate the generalization they favour and not to test it. Would Zeki or Ramachandran tolerate this procedure in their own subject? I expect they’d laugh at it. How easily we shrug off our academic training when we take the brave step outside the furrows we were taught to plough!

Read the full article.

iHuman on podcast

2006-01-19T21:17:00.000+01:00

There is a most interesting question being posed at the ABC The Science Show:

"What are the implications of the latest advances in neural prosthetics?"

THE SCIENCE SHOW with Robyn Williams - iHuman
Saturday 14 January, Midday, repeat Monday 16 January, 7pm

What are the implications of the latest advances in neural prosthetics, electronic implants and robotics for humankind? It started with attachments to the body - the watch, the hearing aid - now we are working with nerves and the brain, having the brain operate motors and activators. Combining man and machine can be used to save lives, but where does it end?

Download the mp3 file directly here (mp3 file) or get the transcript here.

Men's vengeful brains

2006-01-19T20:54:00.000+01:00

While trying to digest the overwhelming yet so short conference on Imaging Genetics in Irvine, I find myself just tapping into some of the latest headlines. This little piece in New Scientist on sexual differences in revenge sounds interesting.

From the New Scientist article:

Tania Singer of University College London and colleagues used a functional magnetic resonance imaging (fMRI) machine to analyse the brain activity of 32 volunteers after their participation in a simple game, called the Prisoner's Dilemma.

The game allows players to cooperate or double-cross one another, and so fosters camaraderie or enmity between players. Following the game, participants were placed inside an fMRI machine and then saw their fellow players zapped with electricity. The activity in their brain was recorded as they watched.

The scans revealed changes in activity as players who had cooperated got zapped, compared with those who had double-crossed them in the game. The results suggest that men get a much bigger kick than women from seeing revenge physically exacted on someone perceived to have wronged them.

So it seems possible that there are sexual differences in how men and women choose their revenge. It does not show, however, that men are more vengeful. But they seem to react more to see their opponents being punished.

Red the full story here and visit Dr. Tania Singer's homepage to read more.

2006: Year of the Neanderthals

2006-01-16T16:16:00.000+01:00

This year it is 150 years ago that miners in the German Neander Valley lucked upon 16 fossils that turned out to belong to a different homo species. The Neanderthals are of special interest to the study of the homo sapiens brain, being bigger in average volume, but (presumably) different in function. Since brains doesn't fossile there are really only two ways of studying this difference: (1) through comparing the DNA of the two species, and (2) through what has been called cognitive archeology - the deduction of how the Neanderthal mind must have been organized through an examination of archeological evidence such as diet, technology and social structure.

If you happen to read German this article in Die Zeit kicks off the Neanderthal year. In July Bonn will host a big conference on the Neanderthals. Its web-site has a number of interesting papers on-line.

Mirror neurons

2006-01-15T17:21:00.000+01:00

On a hot summer day 15 years ago in Parma, Italy, a monkey sat in a special laboratory chair waiting for researchers to return from lunch. Thin wires had been implanted in the region of its brain involved in planning and carrying out movements.

Every time the monkey grasped and moved an object, some cells in that brain region would fire, and a monitor would register a sound: brrrrrip, brrrrrip, brrrrrip.

A graduate student entered the lab with an ice cream cone in his hand. The monkey stared at him. Then, something amazing happened: when the student raised the cone to his lips, the monitor sounded - brrrrrip, brrrrrip, brrrrrip - even though the monkey had not moved but had simply observed the student grasping the cone and moving it to his mouth.

The researchers, led by Giacomo Rizzolatti, a neuroscientist at the University of Parma, had earlier noticed the same strange phenomenon with peanuts. The same brain cells fired when the monkey watched humans or other monkeys bring peanuts to their mouths as when the monkey itself brought a peanut to its mouth.

Later, the scientists found cells that fired when the monkey broke open a peanut or heard someone break a peanut. The same thing happened with bananas, raisins and all kinds of other objects.

"It took us several years to believe what we were seeing," Dr. Rizzolatti said in a recent interview. The monkey brain contains a special class of cells, called mirror neurons, that fire when the animal sees or hears an action and when the animal carries out the same action on its own.

By now mirror neurons is a well-known story. However, if you are not up to speed Sandra Blakeslee has a nice story in NY Times giving a short run-down of the story so far. (The quote above is from that article.) Afterwards, you will probably enjoy a visit to the homepage of the Physiology Lab at Parma University. That's the home of many of the pricipal investigators working on the mirror neuron cells, including Giacommo Rizzolatti, Leonardo Fogassi, and Vittorio Gallese. They have a lot of their research papers on-line.

I'm chiefly mentioning this because I'm going to put up the next installment in my little series on the neurobiology of culture in a few days. (See the first part here.) Here, mirror neurons play a vital part, and you may want to get a head start!

Hardwired Behavior

2006-01-13T09:29:00.000+01:00

This book from Cambridge University Press looks interesting. I haven't actually read it yet, but the new issue of Nature has a rather positive review of it. A brief passage from the review:

Laurence Tancredi’s book Hardwired Behavior powerfully presents science that shows the gross inadequacy of the binary terms we often use to talk about the genesis and character of complex human behaviours. He writes: “Our brain structures are not immutable; they are susceptible to change for the better and change for the worse.” Indeed, much of the research he discusses rests on this neuroplasticity. He reports on research showing that talk therapy can produce neuronal changes. His chapter on gender differences suggests that changing social conceptions of the roles of women “will inevitably affect the biology of their brains over time”. He reports on research showing that rats deprived of nurture at birth fail to express a gene that is correlated with their ability to handle stress. And he refers several times to a fascinating study by Avshalom Caspi and colleagues (Science 301, 386–389; 2002), which found that the likelihood of children becoming antisocial as adults is a function of both their genomes and their experiences. As Tancredi observes, this finding “emphasizes the interactive nature of genes and environment, nature and nurture”.

Tancredei, L. (2005): Hardwired Behavior. What Neuroscience Reveals About Morality. Cambridge University Press.
Publisher's description.

Adult dendritic growth

2006-01-10T11:21:00.000+01:00

Until recently anatomists were convinced that humans are born with all the neurons they are ever going to own. In the first years of life, some of theses neurons are then pruned due to a dynamic selection process. From then on, the only serious change to the brains was thought to come from cell death or inflicted lesions.

Not so. The brain actually continues to rebuild itself throughout life. For instance, new cells are born in the hippocampus. And a new study from a group at MIT demonstrates that adult dendrites of non-pymidal neurons are able to expand their branches. Here's the abstract:

Despite decades of evidence for functional plasticity in the adult brain, the role of structural plasticity in its manifestation remains unclear. To examine the extent of neuronal remodeling that occurs in the brain on a day-to-day basis, we used a multiphoton-based microscopy system for chronic in vivo imaging and reconstruction of entire neurons in the superficial layers of the rodent cerebral cortex. Here we show the first unambiguous evidence (to our knowledge) of dendrite growth and remodeling in adult neurons. Over a period of months, neurons could be seen extending and retracting existing branches, and in rare cases adding new branch tips. Neurons exhibiting dynamic arbor rearrangements were GABA-positive non-pyramidal interneurons, while pyramidal cells remained stable. These results are consistent with the idea that dendritic structural remodeling is a substrate for adult plasticity and they suggest that circuit rearrangement in the adult cortex is restricted by cell type–specific rules.

The paper was published in PLoS Biology which means it is open-access. Go grap it!

Lee, WCA. et al. (2006): Dynamic remodeling of dendritic arbors in GABAergic interneurons of adult visual cortex. PLoS Biol 4(2): e29.

Sorry babe, blame it on my D1-receptors!

2006-01-09T21:33:00.000+01:00

The most recent issue of Nature Neuroscience contains a truly amazing study by the Thomas Insel-group. Insel and his colleagues have for many years studied pair-formation in prairie voles. Earlier, they have demonstrated that dopamine transmission within the nucleus accumbens (Nacc) facilitates partner-preference formation (i.e., that the infusion of dopamine into Nacc makes male pairie voles seek out female mates). In this new paper, they demonstrate that the rostal shell of Nacc actually contains two different dopaminergic receptors that perform functionally different jobs. One type, called D2, facilitates the approach behavior associated with the formation of a pair-bond. The other, D1, maintains that bond, by antagonizing the activity of the D2-receptors. This "faithfulness" is expressed behaviourally by the male voles figthing off other female voles than the partner. Crucially, D1-receptors are upregulated after the pair-bond has been formed. In other words: the male vole's brain changes with having a relationship - it, figuratively speaking, becomes faithful. Thus, the behavioural process of finding a mate, establishing a relationship and keeping it going depends upon a complicated molecular process in parts of the prairie vole's reward system. This result opens at least two exiting new avenues of ressearch: (1) Will we find the same functional system in the human brain? What is the genetic reason for a vole having more or less D1-receptors, i.e. being able to form long lasting pair-bonds?

I personally wouldn't be surprised if Insel one day receives the Nobel prize. Being the director of NIMH shouldn't hurt!

Aragona, B. et al. (2005): Nucleus accumbens dopamine differentially mediates the formation and maintenance of monogamous pair bonds. Nature Neuroscience 9: 133-139.

More on the Sapir-Whorf hypothesis

2006-01-09T12:57:00.000+01:00

The problem with arm-chair hypotheses such as the Sapir-Whorf idea that the language you speak determines how you think, is that they are all-or-nothing contentions. Either language determines thought, or it doesn't. Either the mind is innate, or it is the result of nurture. Things tend not to be so clear-cut. In the next issue of Trends in Cognitive Science Paul Kay and Terry Regier review research done on colour perception - an old Whorfian theme. Turns out that colour naming and colour cognition is neither strictly universal, nor strictly language specific. Say Kay & Regier:

The ‘Whorfian’ debate over color naming and colorcognition has been framed by two questions: (1) Is color naming across languages largely a matter of arbitrary linguistic convention? (2) Do cross-language differences in color naming cause corresponding differences in color cognition? In the standard rhetoric of the debate, a ‘relativist’ argues that both answers are Yes, and a ‘universalist’ that both are No. However, several recent studies, when viewed together, undermine these traditional stances. These studies suggest instead that there are universal tendencies in color naming (i.e. No to question 1) but that naming differences across languages do cause differences in color cognition (i.e. Yes to question 2). These findings promise to move the field beyond a conceptually tired oppositional rhetoric, towards a fresher perspective that suggests several new questions.

This review nicely complements the study Thomas mentions below.

Kay, P. & Regier, T. (In press): Language, thought, and color: recent developments. Trends in Cognitive Science, to appear.

Brushing up the brain

2006-01-08T20:37:00.000+01:00

While we're at it with cosmetic neurology, there is also a nice article by Chatterjee freely available in Neurology. I think the conclusion in this paper says it all:

"In this paper, I have raised issues about cosmetic neurology that our profession will encounter. We may have our personal opinions on the correctness of such “treatments,” but do we have a stand as a profession? We can anticipate facing questions where separating principle from prejudice is not easy and for which there are no easy answers. To make these questions concrete, I invite readers to consider their own views on the following questions:

Would you take a medication with minimal sideeffects half an hour before Italian lessons if it meant that you would learn the language more quickly?
Would you give your child a medication with minimal side effects half an hour before piano lessons if it meant that they learned to play more expertly?
Would you pay more for flights whose pilots were taking a medication that made them react better in emergencies? How much more?
Would you want residents to take medications after nights on call that would make them less likely to make mistakes in caring for patients because of sleep deprivation?
Would you take a medicine that selectively dampened memories that are deeply disturbing? Slightly disturbing?

Such questions are not simply thought experiments. Patients and advocacy groups encouraged by direct advertising to consumers will raise them. How will you respond to these “patients” when they turn to you as the gatekeeper in their pursuit of happiness?"

Remember to take your Targacept

2006-01-08T19:56:00.000+01:00

In the growing field of cosmetic neurology, an approach that seeks to enhance the brain's workings, one branch seeks to develop new drugs that not only help those suffering from memory disorders such as dementia. The question is, if it works in these patients, how would it work in healthy individuals? Several studies on both humans and other primates and mammals now show that our memories CAN be enhanced through pharmacological interventions.

So, now it can be done. Question is: should we do it? I think your answer partially depends on how you view how our brains are constructed and how they work. It seems to me that most people think that the brain (our mind) is more or less are naturally given, and highly adaptive mechanisms. To a certain extent, this is true. However, as Martin's piece on Dehaene's showed, the brain is not a perfect machinery but has inherent and many flaws and shortcomings. memory is a good example. How often have you tried to remember the name of a person standing in front of you -- remembering YOUR name? Or where your put your keys? Simple examples, yes. But they show that our memory is not perfect, at least not as perfect as we'd want it to be (sometimes). Just think of that 8-hours exam you read up to, just for sitting there trying to remember a piece of vital information for a key question.

So are there any memory pills out there? The piece below discusses how Targacept works on the nicotine receptor. To know a bit more on one role of this receptor system, you may also read Nancy Woolf's article in Science & Consciousness Review.

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Targacept compounds show long-lasting improvement in cognition

Winston-Salem, NC, June 30, 2005 – In a review of research to be published in the July issue of Trends In Pharmacological Sciences, Targacept compounds were reported to have a beneficial effect on cognition well after they were no longer present in the central nervous system. For example, in preclinical animal studies, Targacept's compounds TC-1827 and TC-1734 improved cognitive performance for up to 15 and 18 hours, respectively, though the compounds were appreciably metabolized and eliminated in less than an hour.

The authors postulate that the compounds' long duration of effect arises from their ability to normalize levels of acetylcholine, a key neurotransmitter for modulating cognition. This mechanism of action contrasts with currently marketed drugs for conditions marked by impaired learning and/or memory, which can increase, but not normalize, neurotransmitters involved in cognitive processing.
(...)

The economic mammal

2006-01-06T08:29:00.000+01:00

How are economic decisions made? How and why are we social? According to the traditional economic , humans are rational and self-regarding beings. Not so, says recent advances in neuroeconomics, the scientific multidisciplinary approach that studies how we make choices and act socially. On the contrary, our social interactions are thought as driven by strategic (mostly unconscious) incentives. At the least we should not think of ourselves as rational beings that are constantly choosing our own behaviour consciously. This also relates to my ongoing "dethronement" idea, especially step III.

A new article in Science by Colin Camerer and Ernts Fehr presents aspects of this discussion.

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Science 6 January 2006:
Vol. 311. no. 5757, pp. 47 - 52
DOI: 10.1126/science.1110600

Review

When Does "Economic Man" Dominate Social Behavior?

Camerer and Fehr
The canonical model in economics considers people to be rationaland self-regarding. However, much evidence challenges this view,raising the question of when "Economic Man" dominates the outcomeof social interactions, and when bounded rationality or other-regardingpreferences dominate. Here we show that strategic incentivesare the key to answering this question. A minority of self-regardingindividuals can trigger a "noncooperative" aggregate outcomeif their behavior generates incentives for the majority of other-regardingindividuals to mimic the minority's behavior. Likewise, a minorityof other-regarding individuals can generate a "cooperative"aggregate outcome if their behavior generates incentives fora majority of self-regarding people to behave cooperatively.Similarly, in strategic games, aggregate outcomes can be eitherfar from or close to Nash equilibrium if players with high degreesof strategic thinking mimic or erase the effects of others whodo very little strategic thinking. Recently developed theoriesof other-regarding preferences and bounded rationality explainthese findings and provide better predictions of actual aggregatebehavior than does traditional economic theory.

Read more

Science's dangerous ideas

2006-01-04T12:40:00.000+01:00

Every year renowned literary agent John Brockman asks a group of prominent scientists a question and posts their answers at his web-site The Edge. This years question is "what is your dangerous idea". In his reply, French neuroscientist Stanislas Dehaene raises the question of neuro-enhancement. As was the case with the Nation article mentioned below, neuro-enhancement is most often viewed as a dubious affair - potentially dangerous and socially unfair. Dehaene, in contrast, is very much in favour of it. We tend to overlook, he writes, just how inherently limited our brain is. If possible, we should do something about this limitation. An excerpt from his reply:

As we gain knowledge of brain plasticity, a major application of cognitive neuroscience research should be the improvement of life-long education, with the goal of optimizing this transformation of our brains. Consider reading. We now understand much better how this cultural capacity is laid down. A posterior brain network, initially evolved to recognize objects and faces, gets partially recycled for the shapes of letters and words, and learns to connect these shapes to other temporal areas for sounds and words. Cultural evolution has modified the shapes of letters so that they are easily learnable by this brain network. But, the system remains amazingly imperfect. Reading still has to go through the lopsided design of the retina, where the blood vessels are put in front of the photoreceptors, and where only a small region of the fovea has enough resolution to recognize small print. Furthermore, both the design of writing systems and the way in which they are taught are perfectible. In the end, after years of training, we can only read at an appalling speed of perhaps 10 words per second, a baud rate surpassed by any present-day modem.

Nevertheless, this cultural invention has radically changed our cognitive abilities, doubling our verbal working memory for instance. Who knows what other cultural inventions might lie ahead of us, and might allow us to further push the limits of our brain biology?

Read all the - many interesting - answers here.

Language helps vision

2006-01-04T11:28:00.000+01:00

There is no doubt that there are hemispheric differences in the brain. We know that in most people, the left hemisphere is dominant for language production. Damage to the left lateral prefrontal cortex produces the well-known expressive aphasia. On the other hand, language comprehension is seen to involve both hemisphere, or at least that the hemispheric asymmetry is lower.

So much for language. But does language influence the way we perceive things? According to the old Sapir-Whorf hypothesis there is a systematic relationship between the grammatical language a person speaks and how that person both understands the world and behaves in it. In other words, language influences thought. But does language influence "direct" perception as well?

In a recent study in PNAS, Gilbert and colleagues from the Ivry Lab demonstrate that language may play a role in perception. Below is a quote from Nature with further link to the full version. The original article by Ivry can be found here.

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The language-loving left hemisphere of the brain can spot different colours faster than it can identify different shades of the same colour.

Our perception of colours can depend on whether we view them from the left or the right, scientists have found. They say this demonstrates how language can alter the way we see the world.

The idea that language can affect cognition is not new. In the 1930s, the American linguist Benjamin Lee Whorf proposed the controversial hypothesis that the structure of language affects the way people think. Later studies have hinted that this may be true in some circumstances (see 'Tribes without names for numbers cannot count'). But whether language affects our perception of the world has remained an open question.

Richard Ivry of the University of California, Berkeley, and colleagues suspected that separating out the effects of visual input to the right and left brain hemispheres might yield some clues. Language is processed mainly in the left hemisphere of the brain, which also deals with signals from the left side of the retinas in both our eyes.

Because light from objects to our right falls mainly into the left-hand area of our retinas, the researchers hypothesized that colours to the right would feel the influence of language more keenly. Conversely, objects on our left side activate the right hemisphere of the brain, so the effect of language would be minimal.

Full Text at Nature

The Convergence of Brain Structure and Function

2006-01-03T08:36:00.000+01:00

A special issue of Anatomy and Embryology is out, dedicated to the issue of brain structure vs. function. It has several interesting articles, such as the developmental dynamics of the primate brain, historical antecedents to the current structure-function debate, and mirror neurons in the brain. The list of interesting articles is long.

Find the special issue here.

The plastic brain - reviews

2006-01-02T12:51:00.000+01:00

The journal Science has an issue dedicated to brain development and brain plasticity. Models of the brain have changed from viewing plasticity as something occurring only at the early developmental stages to a view stressing a life-long plasticity of the brain. As a result, we need new understandings of how the brain works at all ages, and if there are qualitative stages or changes in the brain between different life age stages, e.g. in how genes are expressed. Neither the mind or its fatty counterpart should be seen as stable over time, and significant changes occur even in the oldest age; changes that are not attributable to degeneration only. even old brains can learn.

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Neuroscience: Systems-Level Brain Development

Peter Stern and Pamela J. Hines
Full article

Our brains show the highest degree of plasticity during the early phases of life. However, not all is lost as we advance in years. A certain level of flexibility and adaptability will be with us throughout life. To fully understand the operations and functions behind these processes, it is not enough to concentrate solely on the molecular and cellular components and their interactions. Nor, at the other end of the spectrum, is the study of higher cognitive functions sufficient: It is often too remote to provide comprehensible mechanistic insight. The leap from cells to thought seems almost infinitely complex, yet every growing child manages to make it. Somewhere in this middle ground, between molecular components and psychology, lie the means by which familial and educational experiences intersect with developmental biology to shape cognitive abilities and personalities. We have thus decided to focus on the systems level instead. This approach has been extremely successful over the years and provided us with a wealth of novel and sometimes astonishing insights. (...)

Nation article on neuroethics

2006-01-02T11:34:00.000+01:00

Neuroethics is slowly beginning to get some attention from the non-academic press. One of the persons responsible for this emerging interest is Martha Farah who has written a number of papers on neuroethics. (Find them here at her homepage.) She has also been instrumental in establishing the Neuroethics Centre at the University of Pennsylvania which has an informative webpage. Recently, she has been named an action editor at the Journal of Cognitive Neuroscience, charged with the task of including papers on neuroethics in the journal.

In the January 9 issue of the journal The Nation Kathryn Schulz has a piece on neuroethics where she interviews Farah and Neuroethics Centre director Arthur Caplan. The article focuses on the two most basic ethical problems that neuroscientific research raises. (1) Implications of insights into brain function. Can the ability to probe people's brains be misused? (As Thomas mentions below, neuroimaging could possibly become a mandatory part of job interviews.) Should our understanding of agency change the legal system? (2) Neuroenhancement. When we come to understand the molecular processes governing the brain this knowledge could potentially be used to change the way people's brains work. This possibility is of course already a reality, with psychopharmacology leading the race, but it will continue to grow in importance. Who should have access to such enhancing drugs and surgery? What part of our mind and personality should be exempt from outside meddling?

In the last part of the article Schulz raises a third ethical problem which has received somewhat less attention. Being a liberal or progressive journal, The Nation is prone to see technological fixes as more dubious than more basic social changes. However, the idea of changing people through social changes pressuposes a plastic idea of the brain: People's values can be changes through their environment. Opposed to this view is "human nature" contention that we are born with a specific set of cognitive faculties that are only malleable to a very small degree. This old nature vs. nuture question is alive and well and concerns our very self-image: What is a human being? Neuroethics should be encouraged to take up such basic philosophical question as well.

Reference

Schulz, K. (2006): Brave neuro world: The ethics of the new brain science. The Nation (January 9, 2006).

You are your amygdala

2006-01-02T10:22:00.000+01:00

Show my your amygdala size and I'll tell you who you are! In a study by Omura, Constable & Canli in the November 2005 issue of NeuroReport (see abstract + links below), the sizes of the right and left amygdalae were compared to assessment of the levels of extraversion and neuroticism. The results indicated that the smaller your right amygdala is the more neurotic you are. A larger left amygdala correlated with being more extravert.

How long before your job application includes a mandatory brain scan? Well, as soon as there is only a correlation between amygdala size and personality inventory subscales then the personality subscales is cheaper to use. But psychological tests are prone to errors and the time of assessment. A brain scan is more objective, since your brain does not alter its shape (dramatically) from day to day. But the amygdala might not be the only place one could test. Depending upon the job we could add brain scans for working memory, visual perception, empathy and social reasoning. It might not be here just yet, but it might very well be within our reach to do this.

The term 'head-hunting' can indeed get a new meaning.

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Amygdala gray matter concentration is associated with extraversion and neuroticism.

Omura K, Todd Constable R, Canli T

Neuroreport. 2005 Nov 28; 16(17): 1905-8

Using high-resolution magnetic resonance imaging and voxel-based morphometry in 41 healthy individuals, this study evaluated the association between the personality traits of extraversion and neuroticism, on the one hand, and individual differences in localized brain volume and gray matter concentration, on the other, with a special focus on the amygdala. Extraversion was positively correlated with gray matter concentration in the left amygdala, whereas neuroticism was negatively correlated with gray matter concentration in the right amygdala. Given that neuroticism is a risk factor for depression, our finding offers one explanation as to why prior structural imaging studies of depressed patients (which did not control for personality) produced conflicting findings. Furthermore, our data are consistent with the view that amygdala reduction seen in depressed patients precedes the onset of the disease, rather than being a consequence of the illness.

The making of false memories

2006-01-02T09:58:00.000+01:00

For many years researchers in cognitive neurscience have known that episodic memory does not work like a tape recorder or a computer hard drive. Recollection of events is not a simple replay from a fixed store. Rather, episodic memory (and memory in general) is today seen as a dynamic - even fragile - reconstruction process. As a consequence, errors can happen, and they do. One of these kinds of recall errors are false memories. But what are the mechanisms behind false memories? Why do things go wrong? In a paper by Lampinen et al. false memories are studied experimentally. They shed light on two special features in false memories; borrowing and vividness.

The mere existence of false memories are serious news for the use of eye witness testimonies, even for victims of violent acts such as rape. If memories cannot be treated as true, but are unstable, influenced by the context in which it is recalled, how can we make use of it at all. Vivid false memories, as described by Lampinen et al., attest that even if a person is certain about his memory about an event they can be false.

The discussion of false memories also applies to the publication of memory's "shaky trace" (PDF) a couple of years ago. It's an interesting finding that memories can be altered and even deleted at the time of retrieval. Put into more practical terms; depending on how you ask your question you will get different answers from memory. What keeps the same is that the person feels that the memory is genuine.

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Compelling Untruths: Content Borrowing and Vivid False Memories

by James Michael Lampinen et al.
Journal of Experimental Psychology: Learning, Memory, and Cognition - Volume 31, Issue 5 , September 2005, Pages 954-963''

Abstract False memories are sometimes accompanied by surprisingly vivid experiential detail that makes them difficult to distinguish from actual memories. Such strikingly real false memories may be produced by a process called content borrowing in which details from presented items are errantly borrowed to corroborate the occurrence of the false memory item. In 2 experiments using think-out-loud protocols at both study and test, evidence for content borrowing occurred for more than half of the false remember judgments participants reported. The present study also provides evidence consistent with recollection rejection and distinctiveness playing a role in false-memory editing.

ScienceDirect

Our inner ape

2006-01-01T15:07:00.000+01:00

Below I discuss the continuity of the human and chimp brains. I also briefly mentioned the much exiting research being done these years on chimp behaviour. One of the primatologists leading this research effort is Frans de Waal. The Guardian just published a review of his latest book Our Inner Ape. Read it here.

Musicians are different from you and me

2006-01-01T13:06:00.000+01:00

You probably knew this already, but now it has been proved: Musicians are different from you and me. Mounting evidence suggests that playing an instrument will literally change your brain to the point, even, of altering your motor system macroanatomically in some cases. In a forthcoming paper in NeuroImage Marc Bangert and his colleagues demonstrate that musicians also use their brains in a different manner. They imaged a group of musicians and a group of non-musicians using fMRI while either listening passively to a piano sequence or arbitrarily pressing the keys on a soundless piano keyboard. They then looked for differences in brain activity between the two groups in accomplishing these two tasks.

The passive listening task yielded more activation in the professional pianist group in premotor and motor cortex, in BA 10, in left inferior and superior temporal gyrus, and in left Broca’s area. The key-pressing task yielded extraordinary activity in the pianists in the medial frontal and precentral gyri, in dorsolateral PFC, in Broca’s area, and parts of the limbic system.

Bangert & Co afterwards performed a conjunction analysis, singling out the areas active more so in the pianist group in both tasks. According to the abstract of the papers

This network is comprised of dorsolateral and inferior frontal cortex (including Broca’s area), the superior temporal gyrus (Wernicke’s area), the supramarginal gyrus, and supplementary motor and premotor areas.

It is hardly surprising that professional pianists recruit a network of brain processes different from that of novices when playing. But that they also listen to music in a different manner – at least using a different neurocognitive system in their brains – is very interesting news. Could it be that their phenomenal experience is also different?

Reference

Bangert, M. et al. (in press): Shared networks for auditory and motor processing in professional pianists: Evidence from fMRI conjunction. NeuroImage, to appear.

Blog introspections

2005-12-31T15:18:00.000+01:00

At the end of this month and year, our stats are indeed looking promising. We have only started to gather statistics from 11. December, and we have already had a good amount of visits. Close to 600 in all in about 20 days -- and doing so without any deliberate ads anywhere (well, except a note at my group, Mind & Brain at yahoogroups).

There are two primary motivations behind this blog. The first is that it serves as an archive for out research on neuroethics, on the road of making a book about it. The book will be written in Danish, but it of course our hope that it can be translated into other languages, e.g. English. So in terms of the book project, we needed somewhere to arhive our items. In extension to this, we also thought a blog would be good for more free thoughts and views in the preparation of the book.

But why should we hold this archive just for ourselves? Why not share this with others? I think the answer is obvious - brain science produces a hole new range of findings that goes straight to the bone of what it actually means to be human. In order to understand these new findings and their implications, there must be a bridge between the researchers and the public (and the media). Martin and I are both cognitive neuroscientists, having our hands in the mud, so to speak. Why let others think about the consequences of what we are doing? Why not discuss this ourselves -- share our thoughts, concerns and visions? In addition, since there is an abundance of brain-hype sites and news, we hope to bring up to date, balanced news and views following the proper scientific rigor!

So while much of what we write is to our own amusement and preparation, we hope that you will be amused with us. And please drop in for comments and discussions. We'd love to hear your opinions.

Cognitive literary studies

2005-12-31T11:26:00.000+01:00

Every year the American Modern Language Association stages a conference where English professors and students from all over the US gather to discuss the state of literary criticism and theory. Think Society for Neuroscience, if you need a comparison.

This year, as Nick Gillespie tells us in this report, the talk focused on cognitive approaches to the study of literature. The old paradigm - postmodernism or whatever you would like to call it - seems to be in decline. Will a cognitive approach be the next big thing?

Well, since literary texts are composed of string of words, and since it takes the processing of neurocognitive mechanisms to make sense of such strings of words, we should certainly hope so! Still, personally I wouldn't hold my breath. It is, though, heartening to see that a few valiant cognitivists are trying to break the anti-biological spell of modern lit-crit.

Anterior cingulate cortex

2005-12-30T12:51:00.000+01:00

The structure of today is the anterior cingulate cortex (ACC). Two new studies jointly illuminate the function played by this intriguing part of the brain. In many imaging studies the ACC lights up in connection with cognitive processing, especially when something goes wrong. Some researchers have speculated that the ACC may work as a cognitive error-detection device. Other studies implicate the ACC in emotional processing (and, traditionally, the ACC has been grouped anatomically as part of the limbic system). So, what is it, cognition or emotion?

In a forthcoming paper in Brain and Cognition, Ray Dolan, Hugo Critchley and their colleagues at FIL in London test two patients with damage to the medial part of the prefrontal cortex (including ACC) on a number of cognitive tasks. They conclude (citing the abstract) that

both patients showed intact intellectual, memory, and language abilities. No clear-cut abnormalities were noted in visuoperceptual functions. Speed of information processing was mildly reduced only in Patient 2 (bilateral ACC lesion). The patients demonstrated weak or impaired performance only on selective executive function tests. Performance on anterior attention tasks was satisfactory.

This suggests, they say, that

our findings are inconsistent with anterior attention theories of ACC function based on neuroimaging findings. We propose that the data may imply that the ACC does not have a central role in cognition. We speculate that our findings may be compatible with the view that the ACC integrates cognitive processing with autonomic functioning to guide behaviour.

As it so happens, another new study by scientists at Stanford and Harvard, reported two weeks ago in PNAS, backs up this conclusion. In this study, subjects used real-time fMRI to modulate feelings of pain by learning to control activity in the rostal part of the ACC. This finding is really quite astonishing, I think! As the authors remark in the abstract to their paper

When subjects deliberately induced increases or decreases in rACC fMRI activation, there was a corresponding change in the perception of pain caused by an applied noxious thermal stimulus. Control experiments demonstrated that this effect was not observed after similar training conducted without rtfMRI information, or using rtfMRI information derived from a different brain region, or sham rtfMRI information derived previously from a different subject. Chronic pain patients were also trained to control activation in rACC and reported decreases in the ongoing level of chronic pain after training. These findings show that individuals can gain voluntary control over activation in a specific brain region given appropriate training, that voluntary control over activation in rACC leads to control over pain perception, and that these effects were powerful enough to impact severe, chronic clinical pain.

The over-all conclusion, thus, appears to be that the ACC do have something to do with the control of behaviour, but mostly with emotional behaviour. Why does it then pop up in so many imaging experiments on cognition? One possible answer could be that the ACC is the neurocognitive seat for integrating emotional responses to some activity or perception with the sequencing of cognitive behaviour. Further research will hopefully tell.

References

Baird, A. et al. (in press): Cognitive functioning after medial frontal lobe damage including the anterior cingulate cortex: A preliminary investigation. To appear in Brain and Cognition.

deCharms, R.C. et al. (2005): Control over brain activation and pain learned by using real-time functional MRI. PNAS 102: 18626-18631.

Culture I: Chimps have it

2005-12-29T15:17:00.000+01:00

The most fascinating scientific result of 2005 – to my mind, at least! – was the sequencing of the chimpanzee genome, reported in the September 1 issue of Nature. (Remember also to read the many accompanying articles on chimp research in the same issue.) Although not the first genome to be sequenced, the chimp genome holds a special importance to research on human cognition and behaviour. The reason for this is the well known fact that chimpanzees are our closest primate relatives. Some 5 to 7 million years ago chimps and the human lineage shared a common ancestor. A comparison of the chimp genome with the human genome will therefore provide invaluable insights into the evolutionary process leading to the creation of homo sapiens. Some interesting finds have already been made. As Elizabeth Culotta and Elisabeth Pennisi write in the Science “breakthrough of year” article that Thomas mentions below

we differ by only about 1% in the nucleotide bases that can be aligned between our two species, and the average protein differs by less than two amino acids. But a surprisingly large chunk of noncoding material is either inserted or deleted in the chimp as compared to the human, bringing the total difference in DNA between our two species to about 4%.

This circumstance feeds a growing suspicion that humans do not so much differ from chimps because of new genes being expressed as because the old genes we share with our chimpanzee brothers and sisters are expressed in a different manner. Various techniques for comparing primate brains (cytoarchitectonics, stereology, imaging) tell much the same story. The human brain is not essentially different from the chimp brain: anatomical areas are more or less arranged in the same manner, it is composed of basically the same cells, and many of the functions it performs are, grosso modo, similar to the functions performed by the chimpanzee brain. There are differences, to be sure. The gene FOXP2, for instance, have mutated twice since the human lineage separated from the chimp lineage. The expression of FOXP2, a trancription factor, is compromised in an English family with a severe speech impediment. Thus, the new variant of foxp2 may have played a role in bringing about human language. Also, Katerina Semendeferi has shown that Brodmann area 10, at the frontal pole of brain, is larger in humans relative to the rest of the brain. Its supragranular layers also appear to form more densely connections with other association areas in the human brain. Yet, it is impossible to say that humans differ from chimps on this or that behaviour which is the product of some new patch of cell tissue, only present in the human brain. We seem to come equipped with a “chimpanzee” brain that have just been modified in a number of subtle ways. Understanding how constitutes one of the great challenges of contemporary science.

On the face of it, chimp behaviour appears to be very different from human behaviour. There are no chimpanzee artists or scientists, for example. No skyscrapers or bridges have been build by chimpanzee engineers and architects. No chimpanzee is blogging from the rainforest of Tanzania about what Jane Goodall is up to these days! For the past 50 years researchers have assembled a long list of putative cognitive cognitive abilities that are unique to humans, and hence contribute to making us different from other primates. However, years of careful observation, and numerous experiments, have, item for item, dismantled this list. Sure, only humans speak, but apes clearly have some semantic capability and are able to refer symbolically to these mental concepts. No chimp will put more than two entities together to form a tool, but they do use sticks to fish for termites, or stones to crack open nuts. Until very recently, most primatologists concurred that only humans are able to read other conspecifics’s minds – that is, that we are the only species to be imbued with a Theory of Mind. It turns out that this is not true. Chimps have ToM as well! Again, tool use, language, and mentalizing, are all clearly different in humans, but they can't be said to be altogether absent from chimps, if you look carefully at the underlying neurocognitive mechanisms. The lesson to be gained from these behavioural studies, once more, seems to be that humans have inherited a more basic capacity from our common chimp-human ancestor and then have run with it.

A case in point is culture. Culture is very much something we associate with humans, and something that from time to time has appeared on the “unique capacities” list. The “human sciences”, to a large degree, simply define their object of inquiry as culture. (In German the human sciences are often referred to as Kulturwissenschaft; in the US much work go under the name “cultural studies”.) In 1999, however, 9 of the world's leading primatologists published a report in Nature where they documented that chimps at 7 African communities have developed cultural differences in the use of tool, or social behaviour. The authors define a cultural tradition as behaviour patterns that are customary or habitual in one community, but absent in others, but which cannot be explained by ecological differences. In a recent review of this research, also published in Nature, one of the authors, Andrew Whiten, note that number of cultural traditions observed in chimpanzee communities greatly exceeds those found in other species. In fact, other mammals, fish and birds commonly only have been associated with just one tradition. 19 have been identified in orangutans. But a repertoire of no less than 40 behavioural variants have been observed in chimp communities, so something appear to have changed throughout primate evolution. The critical question of course being: what?

Does such behavioural traditions really amount to the thing we call human culture? Well, we may point to some obvious differences: there are a lot more than 40 traditions around in human communities; human culture is cumulative (i.e., we build on, and sometimes improve upon, other people’s behaviour); and many thinkers would argue that human culture is just a much about values as about behaviour. Still, the formation and transmission of traditions are without doubt part and parcel of human culture as well. Perhaps the real benefit from comparing chimp and human culture will be an improved notion of what just exactly culture is! (Such as this attempt by Richard Byrne and colleagues amply show.)

Now, what could possibly be the neurocognitive mechanisms underlying the primate ability to form and transmit cultural traditions? Stay tuned for part II!

To be continued…

Byrne, R. et al. (2005): Understanding culture across species. Trends in Cognitive Science 8: 341-346.

Chimpanzee Sequencing and Analysis Consortium (2005): Initial sequence of the chimpanzee genome and comparison of with the human genome. Nature 437: 69-87.

Whiten, A. et al. (1999): Cultures in chimpanzees. Nature 399: 682-685.

Whiten, A. (2005): The second inheritance system of chimpanzees and humans. Nature 437: 52-55.

Tononi's conscious mind

2005-12-29T09:55:00.000+01:00

An article on Giulio Tononi's work on the brain basis of consciousness has just been published in Science & Consciousness Review. Henri Montandon reviews some of the recent publications by Tononi. Excerpt from the article:

"Tononi’s writings are noteworthy for his grounding in phenomenology, and his lucid style of presentation. He has noticed three aspects of conscious experience:

given any definition of “conscious state”, the brain produces an infinity of them;
each conscious state is prime, rather in the sense of a prime number; it cannot be deconvoluted into lesser states. Tononi terms this characteristic the “integration” of a state;
conscious experience unfolds in well defined intervals, about 100 to 200 milliseconds to develop a fully formed sensory experience, about 2 to 3 seconds for a single conscious moment.

It is these three observations which Tononi seeks to understand in his information integration theory of consciousness. He discusses two hypotheses:

consciousness corresponds to the capacity of a system to integrate information
the quality of consciousness is determined by the informational elements of a complex, which are specified by the values of effective information among them."

Seven seconds to dementia

2005-12-28T23:53:00.000+01:00

Yes, every seventh second a new case of dementia develops in the world. Medscape.com reports this from a just published report in The Lancet. Such a number pinpoints the necessity of finding viable solutions to fight degenerative brain disorders. Such an effort must work on many levels; devising new and improved methods for detecting dementia as early as possible; slowing the progression of the disease; finding treatments that halt or even repair neural damage; improving the healthcare of patients suffering from dementing disorders. Approaches are numerous, but we still know little about the mechanisms behind each type of dementia - and there are more than 100 known causes!

With increasing mean age across the world, and with the proportion of elderly growing in the coming years, much effort should be put into the research into neurodegenerative disorders.

From medscape.com

Globally, New Dementia Case Arises Every 7 Seconds

NEW YORK (Reuters Health) Dec 16 - Findings from a review of published studies suggest that every 7 seconds a new case of dementia occurs somewhere in the world.

"We believe that the detailed estimates in this paper constitute the best currently available basis for policymaking, planning, and allocation of health and welfare resources," lead author Dr. Cleusa P. Ferri, from King's College London, and colleagues note.

The researchers used the Delphi consensus method to estimate the global prevalence of dementia. With this method, quantitative estimates are derived through the qualitative assessment of evidence, according to the report in the December 17/24/31st issue of The Lancet. In the present study, 12 international experts used data from published studies to estimate the prevalence of dementia in every World Health Organization world region.

Roughly 24.3 million people currently have dementia and 4.6 million new cases arise every year, the authors state.

A doubling of the prevalence will occur every 20 years, so that by 2040, about 81 million people will have dementia. However, this increase is not uniform; in certain countries, such as China and India, the prevalence will more than double in the next few decades.

The report indicates that the majority of people with dementia, 60%, live in developing countries. By 2040, this percentage will have increased to 71%.

"Primary prevention (of dementia) should focus on targets suggested by current evidence; risk factors for vascular disease, including hypertension, smoking, type 2 diabetes, and hyperlipidemia," the authors state. "The epidemic of smoking in developing countries and the high rising prevalence of type 2 diabetes in Asia are particular causes of concern."

Lancet 2005;366:2112-2117.

Steps to dethronement III – The unconscious agent

2005-12-28T09:54:00.000+01:00

Normally, we humans think of ourselves as rational beings. A decision is made by me – the Agent – and I know perfectly what I want and how to get there. Enter cognitive neuroscience. From a multitude of studies, there is a consensus today that many decisions are not made through overt, conscious processing. A lot of work goes on behind the scenes and shapes the motivation and choices even in complex decision making.

Just think of the studies by Tanya Chartrand and her colleagues, as I wrote about in this article in the early days of Science & Consciousness Review. By presenting motivation relevant words (‘‘success’, ‘failure’ etc.) to subjects subliminally (without their conscious detection) the researchers were able to manipulate how they reacted when being given an easy or hard/impossible task. Without the subjects’ knowledge, Chartrand was able to produce emotional states in her subjects, e.g. being in a bad or good mood, by manipulating the motivational tone of the presented words. Best of all, her subject were not able to determine why they felt as they did.

Another well-supported idea about unconscious processes stem from research into subliminal perception and priming. From Phil Merikle’s article:

“Subliminal perception occurs whenever stimuli presented below the threshold or limen for awareness are found to influence thoughts, feelings, or actions. The term subliminal perception was originally used to describe situations in which weak stimuli were perceived without awareness. In recent years, the term has been applied more generally to describe any situation in which unnoticed stimuli are perceived.”

There are tons of empirical evidence for subliminal perception, and they all point to the fact that our behaviour is influenced strongly by unconscious processes. We are not the conscious, autonomous agents we think we are. At least not in the sense we usually think.

But if not all our choices are made on a conscious and “rational” level, why do we have the experience of being conscious agents of our actions? In a forthcoming interview I’m doing with Professor Shaun Gallagher at the Department of Philosophy, University of Central Florida, the terms agency and ownership are explored. This interview will be published in Science & Consciousness Review very soon. Here is an excerpt of the interview:

“Phenomenologically intentions in almost all cases come already clothed in agency – the ‘who’ question hardly ever comes up at the level of experience. The neural systems have already decided the issue – one way or the other – even if I'm wrong about who is acting, I am still attributing agency.

The mistake is to think that there is a necessary isomorphism between the phenomenological level and the neuronal level. But even if the neuronal processes can be defined as involving three steps, this does not mean that those three steps need to show up in consciousness. The wonderful thing about the "Who system" is that it's neurological – and the results of its activation are hardly ever experientially manifested as "making a decision about who did the action." Rather, the results of its activation are experientially manifested as "X's action" where X is either you or me.

Of course experiments and pathologies may generate or reveal ‘who’ problems, but in normal ecological behavior it is generally clear whose intention/action it is, and as a result, the identification question – "Someone is intending to pick up the apple, is it me?" – just doesn't come up.”

Stay tuned for the full story.

Dennett on Darwinism and ID

2005-12-27T11:09:00.000+01:00

The American philosopher Daniel Dennett - an outspoken atheist - is interviewed by German newspaper Der Spiegel (in English, though!) on the whole ID affair. Find it here.

Also, look out for his forthcoming book, to be published by Viking in February, Breaking the Spell, which takes on religion. We will probaby return to that book here on the blog when that time comes.

Social cognitive neuroscience

2005-12-23T14:01:00.000+01:00

I didn’t mention it in my post below on Fiddick, but his is only one out of eleven papers composing a theme on social cognitive neuroscience in the recent issue of NeuroImage. This exiting new field has only been around for 5-10 years, but it will surely be one of the major research areas to watch in the coming years. More and more evidence have amassed suggesting that homo sapiens is an extraordinary social species. Yet, not much is known about how our brains give rise to this unique cognitive competence. A better understanding of the human social brain may also have practical consequences. For instance, perhaps one day we will come to understand why some people strap on explosives and blow up themselves and others for the sake of some political cause.

I highly recommend a visit to the Emotion and Social Behavior Lab at Caltech, led by Ralph Adolphs. Adolphs is a world leader in social cognitive neuroscience, and has written several fine reviews on its state of the art. These two are especially good:

Adolphs, R (2003). Cognitive Neuroscience of Human Social Behaviour. Nature Reviews Neuroscience, 4 (3), 165-178. (pdf)

Heberlein, AS, Adolphs, R. Functional anatomy of human social cognition. Book chapter, In press. (pdf)

The fact that we are highly social animals has often been used as an argument for cultural relativism. The argument, prototypically, runs like this. The social context (our “culture”) determines how we think. Therefore, the nature of the brain’s neurocognitive mechanisms is irrelevant to an understanding of our “thinking”. Instead, we should analyse the social “facts” of the culture we are immersed in. As Emile Durkheim famously stated in The Rules of Sociological Method: Social fact

"consist of manners of acting, thinking and feeling external to the individual, which are invested with a coercive power by virtue of which they exercise control over him. Consequently, since they consist of representations and actions, they cannot be confused with organic phenomena, nor with psychical phenomena, which have no existence save in and through the individual consciousness. Thus they constitute a new species and to them must be exclusively assigned the term social. It is appropriate, since it is clear that, not having the individual as their substratum, they can have none other than society, either political society in its entirety or one of the partial groups that it includes - religious denominations, political and literary schools, occupational corporations, etc. Moreover, it is for such as these alone that the term is fitting, for the word 'social' has the sole meaning of designating those phenomena which fall into none of the categories of facts already constituted and labelled. They are consequently the proper field of sociology." (Bold added.)

I cannot begin to count the number of times I have encountered this argument. Yet, how could social “facts” possibly inform, or even determine, how we think (“exercise control over us” in Durkheim's words), if they didn’t “interact” in some way with the brain’s neuronal processes? If my thinking, for instance, about gender roles has been influenced by my looking at scantily clothed women in advertising and music videos (a very popular sentiment among some feminists), my act of looking must somehow be able to form concepts of gender roles in my brain. So, clearly some brain mechanisms are involved in this external, social “exercise of control”. (Also, remember that some types of brain diseases, such as autism, radically impair the patient's ability to absorb social "facts".)

Many of the papers in the NeuroImage special issue address this problem of why the human brain is so susceptible to social influence. Social psychology refers to this question as the “power of situation over behaviour”. UCLA psychologist Matthew Lieberman, the editor of the special issue, go through a lot of what is known about how situations influence brain activity, including the peculiar phenomenon of priming. In the conclusion to his introductory remarks he writes:

Much of social psychology is fundamentally paradoxical, at least to the western mind. We tend to believe that we are the captains of our destiny, and yet, time and time again, social psychology has shown that situational factors exert strong pressures on our behavior and often does so without our knowledge. The implications of these and other findings for social cognitive neuroscience are twofold. First, although social psychologists have established these various principles, nderstanding why humans are guided by these principles and when these principles apply remain largely unknown. If social cognitive neuroscience can help to answer these questions it would be a major contribution to our understanding of social cognition. Second, the principles of social psychology apply not only to the subjects in our investigations, but to us, the researchers as well. In the absence of understanding these principles, we are likely to generate social cognitive hypotheses that are unnecessarily naıve. If we are as blind to the power of situational forces and our own ability to construct social perceptions that do not feel constructed, we will be unable to generate experimental paradigms that take these factors into account. Ultimately, a successful social cognitive neuroscience should thoroughly integrate the methods of social cognition and cognitive neuroscience, and also rely in equal parts on the conceptual lexica of these two parent disciplines as well.

After having read Adolphs two papers, you should go peruse the NeuroImage papers as well.

Evolution takes gold

2005-12-23T13:06:00.000+01:00

Just out today, the well-esteemed journal Science has judged the science of evolution to be the top scientific breakthrough of 2005! The ideas of evolution, of course, traces back to Darwin, and even further. So why is 2005 such an interesting year?

As this story from BBC reports, there have been many vital scientific publications that highlight and expand our understanding of evolutionary processes. This includes the publication of the full chimp genome (from a chimp called Clint). As Science writes:

The genome data confirm our close kinship with chimps: We differ by only about 1% in the nucleotide bases that can be aligned between our two species, and the average protein differs by less than two amino acids. But a surprisingly large chunk of noncoding material is either inserted or deleted in the chimp as compared to the human, bringing the total difference in DNA between our two species to about 4%.

Second, 2005 has seen some important publications on the emergence of new species, also called speciation. Science gives many good examples, including this:

...Birds called European blackcaps sharing breeding grounds in southern Germany and Austria are going their own ways--literally and f iguratively. Sightings over the decades have shown that ever more of these warblers migrate to northerly grounds in the winter rather than heading south. Isotopic data revealed that northerly migrants reach the common breeding ground earlier and mate with one another before southerly migrants arrive. This difference in timing may one day drive the two populations to become two species.

Finally, Science mentions something more close to home for BrainEthics - the improval of the human condition through natural science. With the advanced understanding of evolution and comparative studies between humans and non-human species, we may better understand diseases and treatments that are first tried in animal models. This could lead to better models of cognitive processes, how brain disease initiates and progresses, and how medical treatment can be optimised. Advances such as the sampling of the full chimp genome also allows for sorting out the unique traits of the human genome, which in turn may shed light on what makes humans so distinct from other species. In addition, potential treatments using animal models should now take into account the specific genetic makeup of the animal being used. While it has been known for decades that different species -- even strains within species (e.g. rats) -- may produce different results, knowing the full genome offers a whole new way to quantify these relations.

In the end, however, one cannot avoid speculating about the political importance of stressing evolution today. 2005 has indeed been a year filled with increased interest and discussion of evolution, especially in the light of Intelligent Design. So, while Science has indeed the scientific reasons in place to support a 1st place for evolution science, I won't say that the signal value does any harm, either.

Psychological debate. Neuroscience to the rescue!

2005-12-22T20:52:00.000+01:00

Some weeks ago I mentioned the lack of interest in the brain as a serious problem for Evolutionary Psychology. Now, this resistance to neuroscience may be a general misère within psychology – already back in the 1980’s Martha Farah attacked psychologists for fighting over mental imagery without introducing any neurobiological evidence into the debate. Perhaps psychologists are still functionalists at heart, feeling that neuroscience have no bearing on psychological models. However, when you argue that a psychological function is an evolutionary adaptation, as evolutionary psychology do, it becomes rather problematic to leave out the brain part from your equation, since evolution doesn’t actually operate on functions, but on the genome. And the genome, again, doesn’t build functions but proteins which, in the end, build brains and (again again) not functions, by forming molecules. So, if you are interested in psychological functions as evolutionary adaptations, you simply have to through brain processes.

Luckily, some evolutionary psychologists are starting to do exactly that. In the recent December issue of NeuroImage, Laurence Fiddick presents the results of an fMRI study investigating the question if some deontic conditional rules are easier to reason about, since they are “social” in nature, relative to other “non-social” deontic rules of a similar logical form. Leda Cosmides, back in the 1980’s, proposed that social situations are computed by certain, special social cognitive modules, not by a general-purpose, logical reasoning machine. She went on to investigate this hypothesis using Wason’s selection task, albeit only collecting behavioural data. Over the years, several authors have criticised Cosmides’s data for not really demonstrating a content effect, generating a somewhat heated discussion on the topic (see especially David Buller’s book Adapting Minds, MIT 2005). Yet, until Fiddick’s experiment, nobody had tried to see if Cosmides’s putative “social” deontic rules actually activate a particular set of neural structures in contrast to other forms of deontic rules. Here are the results, quoting from the abstract of Fiddick's paper:

Although the rules and the demands of the task were matched in terms of their logical structure, reasoning about social contracts and precautions activated a different constellation of neurological structures. The regions differentially activated by social contracts included dorsomedial PFC (BA 6/8), bilateral ventrolateral PFC (BA 47), the left angular gyrus (BA 39), and left orbitofrontal cortex (BA 10). The regions differentially activated by precautions included bilateral insula, the left lentiform nucleus, posterior cingulate (BA 29/31), anterior cingulate (BA 24) and right postcentral gyrus (BA 3). Collectively, reasoning about prescriptive rules activated the dorsomedial PFC (BA 6/8).

Does these diffuse networks constitute on the one hand a social module and on the other a logical “precaution” module? Hardly. But, as Fiddick (prudently) state, his results do “reinforce the view that human reasoning is not a unified phenomenon, but is content-sensitive.” Human reasoning is thus content-sensitive, but not modular. This is surely progress. Thanks neuroscience!

eSkeptic on Jones

2005-12-22T17:40:00.000+01:00

As a follow-up to yesterday's story about the denial of teaching ID theory in Pennsylvania, eSkeptic has published an in-depth report from the courtroom, as well as the milieu of the trial. From the description of the trial, also referred to as the Kitzmiller et al vs. Dover Area School District (see also this google search):

"Kitzmiller provides an excellent case study of evolution in action; ironically, in this case how the language of creationists has adapted to changing cultural environments. The defense argued that Intelligent Design is an entirely new species unrelated to creation science, and the plaintiffs expertly demonstrated both the clear ancestral relationship between creationism and ID and the selective pressure of higher court decisions that caused the speciation. With that phylogenetic relationship clearly established in the trial, the judge evidently decided that creationism had not mutated enough to survive as the new species of Intelligent Design."

Genetic determination of brain responses

2005-12-21T21:31:00.000+01:00

The trends in brain imaging are turning towards the study of genes in order to better understand individual differences. While much brain recording to date has been focusing on similarities between people, and what differs between groups, new approaches are looking at what produces the individual differences seen in neuroimaging studies. Some of this variation can be explained by influences of genes, and how each individual's brain is built.

Some of the recent findings have been that the genetic polymorphism -- a normal variance in people -- in the seretonin system has an impact on how people's brain react to emotional pictures. In other words, if Kyle has a type A seretonin gene and Paul has type B, Kyle's brain will react more strongly to emotional faces than Paul. In this sense, it has been shown that even within a healthy sample of people, individual differences can be predicted on the basis of the genetic makeup.

In a recently published study by Cohen et al. this same approach is used to determine individual differences in the dopamine system. Here, Cohen and colleagues find that both the genetic makup of the dopaminergic brain system and the level of extraversion (a personality trait) determines individual differences in the brain's reaction to reward in a gambling game.

As such, these studies clearly demonstrate the importance of the genotype in neuroimaging studies. As I wrote in the previous post, evolution operates at the molecular level. Genes operate at the level of proteins in the brain. We do not understand this properly yet, but with the advent of imaging genetics, this issue is being put at the forefront of neuroscience.

Individual differences in extraversion and dopamine genetics predict neural reward responses

Cohen et al in Cognitive Brain Research

Abstract
Psychologists have linked the personality trait extraversion both to differences in reward sensitivity and to dopamine functioning, but little is known about how these differences are reflected in the functioning of the brain's dopaminergic neural reward system. Here, we show that individual differences in extraversion and the presence of the A1 allele on the dopamine D2 receptor gene predict activation magnitudes in the brain's reward system during a gambling task. In two functional MRI experiments, participants probabilistically received rewards either immediately following a behavioral response (Study 1) or after a 7.5 s anticipation period (Study 2). Although group activation maps revealed anticipation- and reward-related activations in the reward system, individual differences in extraversion and the presence of the D2 Taq1A allele predicted a significant amount of inter-subject variability in the magnitudes of reward-related, but not anticipation-related, activations. These results demonstrate a link between stable differences in personality, genetics, and brain functioning.

ScienceDirect

Imaging genomics videos

2005-12-21T18:40:00.000+01:00

When planning my trip to the upcoming "Imaging Genetics" (also called "imaging genomics") meeting in Irvine, January 16.-17, I discovered that they offer videos AND powerpoint slides (as PDF files). This is an invaluable resource that everyone interested in psychology, evolution and the human mind should see and read.

Evolutionary psychology behold: evolution works at the molecular/protein/brain level, not phenotype or behaviour. Well, eventually, yes, behaviour is the outcome. But in order to understand what is really going on, we need to understand the molecular mechanisms at play. Recent books and articles on evolution, evol-psych and modularity don't even discuss what's going on at the brain level. So we are still far from understanding the mechanisms of evolution in psychology. The Irvine video archive is really an eye opener to many. Start with Weinberger's talk. It gives a good overview.

No ID theory in Penn classes

2005-12-21T13:14:00.000+01:00

Here is a definite blow to the ID proponents: Judge John E. Jones in Pennsylvania says no to teaching ID theory in classes. New Scientist has a good story to tell. And please also read the words by Judge John E. Jones himself!

More on this topic (yes, go ahead and read it!)

Onward Christian Soldiers: The Holy War on Science by Robert Todd Carroll
The Tyranny of Design by Henry Gee
The Panda's Thumb - explaining the theory of evolution
TalkDesign.org - critical examination of the ID movement
Understanding Evolution website for teachers (UC Berkeley)
ICONS OF EVOLUTION? Why much of what Jonathan Wells writes about evolution is wrong by Alan D. Gishlick
An examination of Christian belief by Merle Hertzler
The Crusade Against Evolution by Evan Ratliff
Evolution in (Brownian) space: a model for the origin of the bacterial flagellum by N. J. Matzke
Intelligent Design: Humans, Cockroaches, and the Laws of Physics Victor J. Stenger (1997)
Intelligent Design: The New Stealth Creationism by Victor J. Stenger (2000) [pdf format]
Cosmythology: Was the Universe Designed to Produce Us? By Victor J. Stenger
Design Yes, Intelligent No A Critique of Intelligent Design Theory and Neo-Creationism by Massimo Pigliucci
The "New" Creationism by Robert Wright (Slate.com)
'Intelligent Design' Meets Artificial Intelligence by Taner Edis, Skeptical Inquirer (March/April 2001).
Nutty Professors, or Some Addled Academics? Robert A. Baker
NATURALISM IS AN ESSENTIAL PART OF SCIENCE AND CRITICAL INQUIRY by Steven D. Schafersman
Talk Reason - a collection of articles opposing so-called intelligent design theory
Darwin on Religion from his Autobiography
Evolution & Creationism: Terminology in Conflict by Richard Joltes
Unintelligent Design By JIM HOLT
Creationism: God's gift to the ignorant by Richard Dawkins

New book: Neuroethics - Defining the issues in theory, practice, and policy

2005-12-14T15:55:00.000+01:00

While browsing through the Stanford site, I noticed that Illes has edited a book on neuroethics. Why, that's just what we need! I'm going to get a hold of OUP and have them send me a review copy! Hopefully, I'll be able to send some thoughts about this book very soon. Gazzaethics parts 2-4 still awaits, and will be sent out soon.

Here is what it says on OUP.co.uk:

Description

Neuroethics is rapidly developing into a major field in its own right, as new neuroscientific techniques continue to cast light on human behaviour
This first volume on neuroethics brings together a stellar list of contributors to form a ground-breaking interdisciplinary introduction to the field
Includes forewords from Colin Blakemore and Arthur Caplan

Recent advances in the brain sciences have dramatically improved our understanding of brain function. As we find out more and more about what makes us tick, we must stop and consider the ethical implications of this new found knowledge. Will having a new biology of the brain through imaging make us less responsible for our behavior and lose our free will? Should certain brain scan studies be disallowed on the basis of moral grounds? Why is the media so interested in reporting results of brain imaging studies? What ethical lessons from the past can best inform the future of brain imaging?

These compelling questions and many more are tackled by a distinguished group of contributors to this volume on neuroethics. The wide range of disciplinary backgrounds that the authors represent, from neuroscience, bioethics and philosophy, to law, social and health care policy, education, religion and film, allow for profoundly insightful and provocative answers to these questions, and open up the door to a host of new ones. The contributions highlight the timeliness of modern neuroethics today, and assure the longevity and importance of neuroethics for generations to come.

Readership: Neuroscientists, bioethicists, cognitive psychologists, philosophers of law and mind

Readership: Neuroscientists, bioethicists, cognitive psychologists, philosophers of law and mind

Contents

* Part I - Neuroscience, ethics, agency and the self
* 1 Patricia S. Churchland: Moral decision-making and the brain
* 2 Adina Roskies: A case study in neuroethics: the nature of moral judgment
* 3 Stephen J. Morse: Moral and legal responsibility and the new neuroscience
* 4 Thomas Buller: Brains, lies and psychological explanations
* 5 Laurie Zoloth: Being in the world: neuroscience and the ethical agent
* 6 Erik Parens: Creativity, gratitude and the enhancement debate:
* 7 Agnieszka Jaworska: Ethical dilemmas in neurodegenerative disease: respecting patients at the twlight of agency
* Part II - Neuroethics in practice
* 8 Ronald M. Green: From genome to brainome: charting the lessons learned
* 9 Franklin G. Miller & Joseph Fins: Protecting human subjects in brain research: a pragmatic perspective
* 10 Michael S. Gazzaniga: Facts, fictions and the future of neuroethics
* 11 Judy Illes, Eric Racine & Matthew P. Kirschen: A picture is worth 1000 words, but which 1000?
* 12 Turhan Canli: When genes and brains unite: ethical implications of genomic neuroimaging
* 13 Kenneth R. Foster: Engineering the brain
* 14 Megan S. Steven & Alvaro Pascual-Leone: Transcranial magnetic stimulation and the human brain: an ethical evaluation
* 15 Paul J. Ford & Jaimie Henderson: Functional neurosurgical intervention: neuroethics in the operating room
* 16 Robert Klitzman: Clinicians, patients and the brain
* Part III - Justice, social institutions and neuroethics
* 17 Henry Greely: The social effects of advances in neuroscience: legal problems, legal perspectives
* 19 Martha J. Farah, Kimberly G. Noble and Hallam Hurt: Poverty, privilege and brain development: empirical findings and ethical implications
* 20 Paul Root Wolpe: Religious responses to neuroscientific questions
* 21 Maren Grainger-Monsen & Kim Karetsky: The mind in the movies: a neuroethical analysis of the portrayal of the mind in popular media

Neuroethics: Spreading the word to the world

2005-12-14T15:31:00.000+01:00

There is an article in Nature Reviews Neuroscience by Illes et al. on neuroethics. The article especially focuses on how neuroscience is presented to the public, e.g. through media, and how this practice differs throughout the world. It is interesting to see how neuroethical discussions and the distribution of neuroscience knowledge differs, from Sweden to Venezuela. Not only are the practices spread, but the initiatives are very different both in terms of who initiates the process and what the motivation is.

These divergent initiatives should probably all be implemented around the world, and should be a source of inspiration for how to involve the broader public in discussing neuroscience.

Read also more about Judy Illes here, and remember to visit the Stanford Center for Biomedical Ethics.

International perspectives on engaging the public in neuroethics
Judy Illes, Colin Blakemore, Mats G. Hansson, Takao K. Hensch, Alan Leshner, Gladys Maestre, Pierre Magistretti, Rémi Quirion and Piergiorgio Strata
Published online: 1st December 2005
p977 | doi: 10.1038/nrn1808
Our fascination with the workings of the human mind is an age-old phenomenon. During the past few years, the advancement of neuroscience research has captured the public's imagination and brought about an increasing awareness of the associated ethical, legal and social issues. Illes et al. present global initiatives for engaging the public on these issues and discuss the opportunities and challenges in the burgeoning field of neuroethics.
Abstract | Full text | PDF (110kb)

Allowing comments -- a typo

2005-12-13T09:25:00.000+01:00

I just discovered that the settings for the blog was set to accept comments by registered users only. I've now changed this setting to accept all comments. At least for now -- I have no idea if this opens up a spamming pandemonium.

But anyway, please send us your comments and thoughts about these issues. We are always open for comments and discussions about what brain science means to YOU.

Dethronement step II – Just Another Animal

2005-12-12T10:35:00.000+01:00

Thanks to Martin for filling me in on Freud. It's notable that in the second criticism of human megalomania Freud mentions Darwin. Not because this is wrong, but rather because his own theory of the human mind has been criticised for using an outdated version of evolution, namely Jean-Baptiste Lamarck and his theory of "inheritance of acquired traits" (see also Lamarckism).

Recently, Scientific American declared Charles Darwin to be the most influential scientist of the past millennium. (The subtitle on the cover was "Sorry, Einstein . . ."). In other words, the idea of evolution is considered the most important scientific idea through the modern history of man (well, at least the past millennium). Although Darwin was cautious to mention humans in his first works, he later made more explicit remarks about the phylogeny of mankind.

There is little doubt that Darwinism has not gained the wide acceptance that the Copernican world view has had for a long time. The proponents of Intelligent Design (hush-hush!) claim to challenge evolutionary theory. But let’s be frank: the ID idea is NOT a scientific theory. It has not generated ANY testable hypotheses, and it does NOT explain empirical data any better than Darwinian evolutionary theory. It’s that simple. Really! But in addition, let’s just mention the idea of Unintelligent Design. After all, if the designer of animals, humans and everything was Intelligent, why are there so many examples of unnecessary – or even harmful – body parts? For example, why do we have a blind spot in each eye? What is the veriform appendix for? See also this section for the main criticisms of the ID idea.

The aspects of Darwinism are – sadly – still not accepted generally. So, while reading the Freud citation from Martin, I still wonder why the same diagnosis of human megalomania applies today. I will not dwell into the reasons to this here, other than point out that there is a clear tendency for religious people to reject evolutionary theory. So this is the current status of the road to human dethronement. OK, we’ll accept that we’re not the Centre of the Universe. But hey, don’t make me think that I’m just some ape!

Freud's "wounding blows"

2005-12-10T12:22:00.000+01:00

It may be somewhat tedious to comment on something written by one's blog partner, but just to clear up who first formulated the idea of three major upheavals in human thought quoted by Thomas in the post below: It was, in actual fact, Freud, who, ever modest, singled out Copernicus, Darwin and himself as the three culprits! Freud presented this idea for the first time in his Introductory Lectures to Psychoanalysis which can be found in volume 15 of the Standard Edition of his works. The passage runs as follows:

"But in thus emphasizing the unconscious in mental life we have conjured up the most evil spirits of criticism against psycho-analysis. Do not be surprised at this, and do not suppose that the resistance to us rests only on the understandable difficulty of the unconscious or the relative inaccessibility of the experiences which provide evidence of it. Its source, I think, lies deeper. In the course of centuries the na‹ve self-love of men has had to submit to two major blows at the hands of science. The first was when they learnt that our earth was not the center of the universe but only a tiny fragment of a cosmic system of scarcely imaginable vastness. This is associated in our minds with the name of Copernicus, though something similar had already been asserted by Alexandrian science. The second blow fell when biological research destroyed man's supposedly privileged place in creation and proved his descent from the animal kingdom and his ineradicable animal nature. This revaluation has been accomplished in our own days by Darwin, Wallace and their predecessors, though not without the most violent contemporary opposition. But human megalomania will have suffered its third and most wounding blow from the psychological research of the present time which seeks to prove to the ego that it is not even master in its own house, but must content itself with scanty information of what is going on unconsciously in the mind. We psycho-analysts were not the first and not the only ones to utter this call to introspection[1]; but it seems to be our fate to give it its most forcible expression and to support it with empirical material which affects every individual. Hence arises the general revolt against our science, the disregard of all considerations of academic civility and the releasing of the opposition from every restraint of impartial logic" (Standard Edition, 15, 284-5).

Of course, Freud's idea has since been reformulated many times, by many authors.

Four (was: three) steps to dethronement

2005-12-09T13:09:00.000+01:00

Throughout the history of mankind, religious beliefs have been numerous and manifold. The Egyptian belief in Ra, the Greeks in Zeus, the Vikings in Odin, and today’s belief in God, Allah, even Lucifer, shares some basic similarities. First, the belief in human centralism; that humans are (part of) the centre of universal historical events, and that God (or gods) is paying special attention to humans.

Second, humans are unique and qualitatively different from other species, and that they are the creation of a divine being. They are not only different in terms of physical, even mental, abilities. Humans are closer to the Divine Being.

Third, folk psychology tells us that each (normal) person's actions is the result of rational, conscious thought. We are the conscious, autonomous agents of our behaviour.

Finally, there is a belief that humans consist of two substances or dimensions: the physical body and the immaterial soul/mind, and that when the body ceases to exist the soul will go on.

These assumptions have been questioned by scientific discoveries long before the studies of Nicolas Copernicus and his peers. But let us recap these events briefly and contrast them to three religious dogmas presented above. We can think of these controversies in three areas: the universal centeredness of human beings; the uniqueness of human beings; and the body-soul division. In this and three following posts, I will argue that while today’s modern world does not believe in a pre-Copernican world view, the implications of Darwinian evolutionary theory have yet to be understood and endorsed in its entirety. Finally, results from the scientific studies of consciousness imply that the human mind can be explained by brain structure and function alone.

And yes, this is kind of a rehash of earlier claims about human self-perception. Martin mentions that it might be Freud that once said this. I’m not sure. Anyway, I still think the idea is neat. And notice that the previous version had three steps, while I noticed that due to current consciousness science, we can add a fourth step.

Step 1 – Decentralizing Earth

No doubt, the Copernican revolution changed the way people would eventually look at the skies and how Earth was situated in cosmos. The belief that the Earth is situated at the centre of the universe was overthrown by three cornerstones in modern science: theory, observations and the willingness to re-evaluate current thought. Even in modern science, the latter is an attribute hard to find among scientists. Today, few dispute the Copernican principle that the motion of the heavens can be explained without the Earth being in the geometric centre of the system.

This is probably the easiest step, as it is also the least controversial. But it is a clear example of how scientific discoveries, over time, can influence the way in which we think of ourselves and our position in the universe.

Next step: "Evolving Sapiens"

From face to brain transplant

2005-12-06T14:35:00.000+01:00

There has been an enormous fuss lately about the transplant of face parts from a dead donor to a woman. See some of many google links here. The idea of having another person's face has probably lead many to think about (their own) personal identity. Would you recognise the new face in the mirror as your own? You probably will through association over time. But will it actually "feel" as yourself? This is a totally new issue to which a door now has been opened. Well, at least if this not a one-time show.

As the limits - technical and ethical - of transplants are now being pushed further, what is up next? What if my hippocampus started to shrink, and my memory or learning ability was fading? Would I accept the offer of receiving a fresh hippocampus from a donor? In years to come, we may well be offered this opportunity. In principle, there would be little difference between receiving a donated heart, liver, finger or brain part. But would the inclusion of the hippocampus lead to that other person's private memories? I guess the chances for this scenario are non-existent. The brain (and the hippocampus) does not work that way.

Chance is that the first brain transplants would first be performed in "not-ethically-dangeours" areas, such as the brain stem (e.g. in Parkinsonism), or the primary visual cortex. But what if I was offered a new amygdala, or spare parts of my orbitofrontal cortex? These areas are tightly coupled to emotional reactions and "personality" (yes, a mongrel concept).

How likely is it that this can be done on purely technical grounds? Well, to tell you the truth; it's here already! In 1989 Lehman et al. transplanted the suprachiasmatic nucleus (see image below) from one hamster to another. This nucleus is strategically positioned below (i.e. "supra) the optic chiasma, where the two visual projections from the eye cross. It is known to play a significant role in regulating the sleep-wake cycle, and that ablation of this nucleus permanently disrupts the so-called circadian rythm.

Lehman et al. were able to remove the suprachiasmatic nucleus from one hamster. As expected, this led to a disruption of the dicradian rythm of the animal. Then, a suprachiasmatic nucleus was transplanted from another hamster. What happened was that the circadian rythm - the sleep-wake cycle - of the first hamster was restored! In other words, the sleep cycle of the first hamster could be "repaired" by another hamster's brain part.

So, brain transplants are certainly feasible as future operations in humans! The questions are therefore: would you accept a brain transplant? Should we do this? Could we draw legal lines between "acceptable" and "unacceptable" spare brain parts? Is the hippocampus OK for transplant but the amygdala not?

SCR Reloaded

2005-11-22T10:14:00.000+01:00

For those of you interested in consciousness science, the new online journal/e-zine/forum for the scientific study of consciousness, Science & Consciousness Review, is now online.

New features include comments by registered users, databases, an annotated bibliography, RSS feeds and surveys.

Visit SCR here.

Neurobiology of human values I

2005-11-21T21:55:00.000+01:00

Modern brain science has made a big impact on numerous issues, not the least on health care. The invention of psychopharmacological agents was the first break-through in human history in the treatment of psychiatric diseases.

The consequences of neuroscience may, however, be felt most at all in our self-conception, in how we view human nature. A very clear example of how profound investigations into the brain have upset very deep seated convictions about human nature is the research started by Thomas Willis and his Oxford circle in the 1660’s. By empirically examining both human and animal brains Willis demonstrated that not only bodily, but also cognitive functions, were governed by physical (albeit, at that time, still unknown) processes located in the grey matter of the brain. This conclusion effectively broke with a more than 2000 year old psychological model where bodily and cognitive function were commanded by different parts of the soul – most dramatically in Descartes’ philosophy of mind, where the bodily functions were imagined to be controlled by wholly material forces, whereas “the mind” were seen as non-material. In fact, it is fair to say that this break in our self-image was so powerful that we haven’t really come to terms with it yet. The story of Willis’ groundbreaking work is told masterfully in Carl Zimmer’s informative and very entertaining book The Soul Made Flesh.

In many ways, though, the revolution of Willis pales beside the neuroscientific results obtained in the last 30 years. We are now on the brink of understanding how the very brain processes Willis could only speculate about actually work. Some processes, early vision and memory consolidation for instance, are already quite well understood, even on a molecular level. And the invention of brain imaging techniques – PET, fMRI, MEG, etc. – has made it possible for brain scientists to start digging into even more mysterious and opaque faculties of the human brain such as decision-making, future planning, mathematical reasoning, and language…In short, all the higher-order cognitive faculties we consider the defining and unique traits of the human species. Already, this research is turning out some rather unexpected surprises. Consider, for example, how studies of human economic decision-making have shown the reward and punishment system – the basal ganglia, nucleus accumbens, amygdala, OFC, and other structures – to be critically implicated. Processes in these structures are highly dependent on neurotransmitters such as dopamine and serotonin. As it turns out, these molecules play much the same role in rat and monkey striatum, with dopamine, for instance, contributing to reward-prediction processes. Thus, behaviour such as economic wheelin-n-dealin, hitherto considered a strictly human ability, setting us apart from the rest of the animal kingdom (perhaps even elevating us to a superior, non-animal level of the great chain of being...), has at least some root in neuronal mechanisms that have been around for millions of years and which we share with other animals.

Throughout the last century economic behaviour were explained through mathematical models – utility functions and game theory. Now this approach is being turned on its head…or actually inside the head, as it were! Economics is slowly becoming neuroeconomics. And, similarly, philosophy is becoming neurophilosophy, sociology is becoming social neuroscience, aesthetics is becoming neuroaesthetics, etc., etc. This is perhaps next big revolution brought about by the neurosciences: putting the humanistic sciences on a biological footing, exchanging cultural analysis for neuroscientific experiments!

The coming days I will post discussions of a new book that epitomizes this neurobiological Kehre. Based on a symposium held this January in Paris, Jean-Pierre Changeux, Antonio Damasio, Wolf Singer, and Yves Christen have published a small book called Neurobiology of Human Values. This is really a remarkable title, since more than anything human values have been the foundation that the whole enterprise of a specific “human” science (Humanwissenschaft), in contrast to the natural sciences, have been built on. Human values, the argument runs, cannot be captured by natural laws (since they are changing and subjective), and therefore human behaviour cannot be the subject of the natural sciences but must be investigated by way of a particular “humanistic” methodology. As Changeux et al.’s book shows, this argument no longer holds up to scrutiny. The many experiments reported in the book’s papers demonstrate that it is, in fact, possible to unveil the neuronal processes underlying human values.

At the same time, the book is also important because its authors are almost all very senior and influential neuroscientists – besides the editors, there are chapters by, e.g., Frans de Waal, Richard Davidson, Nobel laureate Daniel Kahneman, Giacomo Rizzolatti, and Stanislas Dehaene. This will lend important credibility to the ongoing study of human values, a research topic which is yet not mainstream in the neuroscientific community. Thus, although it has its shortcomings (most of all, very sloppy copy-editing), Neurobiology of Human Values is a very welcome publication which deserve mentioning.

In coming days I will go through some of issues raised by the book, including aesthetic values, social values, ethical values, and economic values. And what exactly is a value, then? Stay tuned for the answer to that big question!

More Literary Darwinism

2005-11-18T19:12:00.000+01:00

In response to my post on Literary Darwinism, Joseph Carroll has updated his web site, adding not only the Buss chapter I cite, but also several new in press papers. Get 'em here.

Literary Darwinism and the brain

2005-11-18T03:18:00.000+01:00

The November 6 issue of the New York Times Magazine ran a piece by D.T. Max on a new literary theory called ”Literary Darwinism” (LD). LD is the most prominent part of a larger movement called Biopoetics, dedicated to investigating the evolutionary background of the human capacity for producing and consuming works of art. As is well known, the emergence of anatomical modern homo sapiens is associated with a “creative explosion” some 50.000-75.000 years ago – exactly when is still hotly debated by archaeologists and paleontologists – which included, among other things, the first appearance of works of art. (Again, some experts argue that the first works of art appeared earlier, and, indeed, we cannot be completely certain that older hominids didn’t produce non-fossilized art such as, for instance, songs or stories; we can, however, be pretty sure that art, in any meaningful sense, was invented by some member of the homo lineage, and not too long ago.) Thus, the existence of art seems to depend upon some neurocognitive mechanisms that are only found in the human brain. It is of obvious interest to understand not only what these putative mechanisms amount to, but also why the human brain ended up being equipped with them. Biopoetics is dedicated to answering this last question.

If you are at all convinced that humans are biological organisms, this endeavour shouldn’t upset you much. I personally find it pretty obvious that any true understanding of the phenomenon of art calls for a concerted examination of the three old questions: what, how, and why? Without a description of the kinds of language constructions that make for a metaphor (what), a break down of the neuronal processes “running” these constructions (how), and an explanation of why the human brain – perhaps in contrasts to brains of other species – has picked up these processes (why), a theory of what a metaphor is cannot really be considered complete. Yet, as it turns out, most scholars studying art and language only focus on the what-question and disregard the question of how behaviour is grounded in neurobiology. Indeed, many (for reasons I won’t speculate on here) even find this question orthogonal to what a real inquiry into art or language should be about. There are therefore a lot of humanistic scholars to whom any introduction of biology, such as exemplified by Biopoetics and LD, into the study of human behaviour will be like a red rag to a bull.

No doubt this is main the reason New York Times Magazine find LD important enough to warrant a whole exposé. (I don’t think that I offend anybody by saying that LD is still very much in its infancy: Max tells us that there are in fact “only 30 or so declared adherents [of LD] in all of academia”, and most of the work done on LD to this day is of the sort that Joseph Carroll, the theoretical leader of LD, calls “Darwinian literary criticism” – interpretations based on insights gleaned from evolutionary science. Actual attempts to answer the why-question, “why did the human brain come to be able to produce and consume literature?”, are few and far between.) The main story of Max’s article is certainly that here is something new, something different from mainstream postmodern theory. That’s ok. But I think it should be stressed that Max’s introduction to LD is very cursory and doesn’t go much into its theoretical assumptions at all. (For instance, it doesn’t discuss LD’s heavy reliance on Evolutionary Psychology (EP) and EP’s hypothesis that the mind is massively modular, with each module having been adapted for some specific task. Both the notion of a massively modular mind and the human mind as adapted can be criticized; I will return to this discussion in some later post when I get my hand on The Literary Animal, the anthology of papers on LD that prompted Max’s article.) For a more in-depth presentation the reader should really go to Joseph Carroll’s homepage where it is possible to download a sizeable part of Carroll’s papers, albeit not his most recent introduction to LD which can be found in David Buss’ new Handbook of Evolutionary Psychology.

Max’s article does, however, raise an interesting and important point: that LD would benefit immensely from incorporating brain science into their evolutionary framework. I think this suggestion is a very apt and timely memento. The fact of the matter is that, until recently, both LD and Evolutionary Psychology as a whole have more or less completely neglected the what-study, i.e., how brains actually process literary language. And the reason for this negligence has not only been a pragmatic division of labour, but a problematic commitment to a functionalist stance that goes back to John Tooby and Leda Cosmides manifest “The Psychological Foundations of Cuture” in The Adapted Mind; a functionalist stance that deems that genes and neurobiology are not really relevant to understanding biological functions. This stance is problematic since evolution not really works on “functions” but on genes and, consequently, on the cell biology of the brain. Also, as Marc Hauser has stressed, comparing how “functions” are instantiated in different brains is actually a very powerful way of getting at the evolutionary why-question…Comparing chimpanzee to human speech, for instance, will tell us something about how the speech system has changed in hominids since chimps and humans parted way some 6 million years ago. It is therefore very gratifying to now read that no less a figure than Edward Wilson, the doyen of adaptionist studies, points to neuroimaging as a way of advancing LD and evolutionary studies in general. Writes Max:

Edward Wilson told me that he is confident neurobiology can help confirm many of evolutionary psychology's insights about the humanities, commending the work to "any ambitious young neurobiologist, psychologist or scholar in the humanities." They could be the "Columbus of neurobiology," he said, adding that if "you gave me a million dollars to do it, I would get immediately into brain imaging." In fact, you won't always need a million dollars for the work, as the cost of M.R.I. technology goes down. "Five years from now, every psychology department will have a scanner in the basement," says Steven Pinker, a Harvard cognitive psychologist. With the help of those scanners, Wilson says that science and the study of literature will join in "a mutualistic symbiosis," with science providing literary criticism with the "foundational principles" for analysis it lacks.

It should be noted, though, that, due to various technical limitations, much of what is interesting about literature will be very difficult to investigate in a MR-scanner. Long stretches of discourse doesn’t really make for good experimental stimuli, and we really need a good model of “literary cognition” before being able to design interesting fMRI experiments. But, it is definitely the way to go, and I hope that we will soon see some of the people working within LD take a more keen interest in the brain.

References:

D.T. Max (2005): The Literary Darwinists. New York Times Magazine (November 6).
Joseph Carroll (2005): Literature and Evolutionary Psychology. In D. Buss (ed.): Handbook of Evolutionary Psychology. John Wiley.

Rennie gives the pope some directions!

2005-11-14T20:32:00.000+01:00

Having mentioned the new blog at Nature.com, it should also be noted that John Rennie, the editor of Scientific American, writes a regular blog worth surfing by from time to time. In the most recent post (dated November 13), as I'm writing this, Rennie scolds the pope's embarrasing endorsement of Intelligent Design. According to the Associated Press the pope

...quoted St. Basil the Great, a 4th-century saint, as saying some people, "fooled by the atheism that they carry inside of them, imagine a universe free of direction and order, as if at the mercy of chance."

But, as Rennie remarks,

...I don't think most scientists would say that the universe is directionless or chaotic. Randomness is a fact of nature in many physical processes (e.g., radioactive decay and mutation), but there are also organizing principles at work (e.g., the laws of thermodynamics) that do impose a direction as well. For instance, creationists like to say that it's impossible for random evolution to produce order, but evolution isn't random: natural selection is an orderly directional process that acts on the randomness introduced by mutation. Thus it's not clear whom the Pope is really rebuking with this comment.

Rennie, in older posts, does a great job of rebuking the spectre of ID. It is very gratifying to see the editor of one of the major vehicles for the popularization of science take a stand against this concerted effort to suspend the scientific inquiry into the nature of homo sapiens.

Gazzaethics I

2005-11-12T00:31:00.000+01:00

What does a member of the US President’s Council on Bioethics think about the consequences of brain science? How does is knowledge about the brain influencing bioethical decisions? Michael Gazzaniga is a world-renowned neuroscientist and one of the very founders of modern experimental cognitive neuroscience. He is also a member of the Bioethics Council. In his recent book, The Ethical Brain, Gazzaniga not only presents the new discipline of ‘neuroethics’. He is also putting forth his own views on the vital matters. In many ways, Gazzaniga’s own take on the ethical problems are indeed the most interesting parts of the book, and they will surely be found provocative by a lot of readers.

Although the book is relatively small (178 pages plus endnotes) and written as a popular science book, the issues treated here – and Gazzaniga’s views – are well worth a closer look. Despite that Gazzaniga sometimes takes logical leaps from premise to conclusion, the book is clearly a most accessible and entertaining book. As member of the Bioethics Council, Gazzaniga has an impact not only on US law and ethics, but potentially a worldwide influence on how we think about ourselves and others, about free will, when life begins and ends, and on brain enhancements. So let me start by taking on one part at a time; life-span ethics, brain enhancement, brain and the law, and “universal ethics”

“An egg and a sperm is not a human. A fertilized embryo is not a human – it needs a uterus, and at least six months of gestation and development, growth and neural formation, and cell duplication to become a human.” (p. 11)

Gazzaniga leaves no doubt that there are specific boundaries for what can be called a human and what cannot. A fertilized embryo goes through a series of necessary steps before becoming the complex organism that makes up a human baby. But where along this development do we draw the line of what is human, a being to be given rights as any other human being? Anti-abortionists make use of the “continuity argument” which states that a fertilized egg will go on to become a human being and therefore deserve the rights of an individual. In this view the embryo is a (potential) human being from conception and onwards that should be given rights accordingly. This stands in sharp contrast to today’s practice in many countries worldwide, accepting abortion before the embryonic age of 23 weeks.

In order to make good judgements about these issues, says Gazzaniga, we need to consult scientific evidence. Based on findings from neuroscience, Gazzaniga refers to the development of the brain (and mind). It is now well-know that it is only in weeks 5 to 6 that the first electrical brain activity occurs. However, this activity is much too crude to be called “brain waves”, which is the assembly of neuronal populations working together, and a hallmark of mental life. It is first around week 23 that synapses start to form and lay the ground for coherent assemblies of brain activity. In order to see the relevance of these brain waves we should look at the other end of the life line: brain death. The complete and irreversible cessation of brain activity is the clinical hallmarks of the end of life. This is an uncontroversial fact across countries and religions. Practice on the determination of brain death may vary between countries and regions, but the basic assumption that brain death signifies mental death is considered a well established fact today.

The following concluding argument is obvious: while neural activity can be found in brain dead patients, the incoherent, scattered and unorganized activity found – and signifying death – here corresponds to the activation found in embryonic stages up until around week 23. Before that, the neural activation does not represent any integrated thought or behaviour. The embryo is not a mental being before week 23.

What, then, about the continuity argument? As mentioned, there are those who claim that any fertilized egg will continue to grow into a human, and that because of this a fertilized egg should be given the same rights as you and me or any other human. This argument moves beyond the current state of the embryo, basically stating that the human “soul” is present right at or after the fertilization of the egg. Gazzaniga replies here by addressing what he calls the “potentiality argument”; the view that “since an embryo or fetus could become an adult, it must always be granted equivalent moral status to a postnatal human being” (p. 11). The premise here (always look for the premises!) is the assumption that a fertilized egg will always develop into a human being. However, such a view is based upon an uninformed view of fertilization and embryonic development. During the first fourteen days both twinning and chimeras may occur. That is, the fertilized can become two individuals, or it can split into twin eggs and then move back into one egg again. This is in stark contrast to the continuity argument. Otherwise, we should be talking about splitting souls and chimera souls, right?

Gazzaniga gives us a new perspective on ethics; our moral decisions should now be informed by the best possible available evidence on a subject matter. We should not be led by our gut feelings or implicit assumptions about such complex mechanisms as the growth of a human embryo. In order to make sound decisions, we must consult the evidence.

Are you ready for action?

2005-11-10T22:34:00.000+01:00

We are not the only ones starting a serious blog these days. We are being dwarfed by Nature Neuroscience’s (NN) new feature, a blog called Action Potential. And yet, this is very likely one of the resources we will get our material from. A brief look at the blog tells us that it is an attempt at giving the journal a face outwards. To many (most) of us, NN is really one of the top journal to get a publication. Any source that can give a better understanding of what goes behind the scenes in NN is great! And see, they also announce talks about how to get published in NN!

About the purpose of the blog, it says:
“Action Potential is a blog by the editors of Nature Neuroscience - and a forum for our readers, authors and the entire neuroscience community. We'll discuss what's new and exciting in neuroscience, be it in our journal or elsewhere. We hope for spirited conversation!”

If things work out for Action Potential, we hope to see plenty of discussions, news and headlines both from NN, Nature as well as other journals. But it seems to depend on the activities of the visitors; you and me. Why not pay Action Potential a visit and join the discussions?

So, a welcome from us Lilliputians; we’ll be watching you.

Ethical Decision-Making. A new Review.

2005-11-03T13:22:00.000+01:00

Why are some types of behaviour deemed wrong or good? Much of the philosophical work dedicated to this question has been focused on what could be called its metaphysical dimension: How can we determine if some act is good or bad by necessity, and should therefore be considered good or bad by all people? Recently, however, a growing number of researchers have begun to look into its neurocognitive dimension: How does the human brain decide whether or not a behavioural act is good or bad? Two researchers have more than anyone pioneered this approach: a philosopher-cum-psychologist, Joshua Greene, and Jorge Moll, a neuroscientist. Both have conducted a number of imaging experiments trying to illuminate which processes takes place when we make an ethical decision.

Now Moll, together with renowned neuroscientist Jordan Grafman, has published an interesting review of this research so far, which can be found in the October issue of Nature Reviews Neuroscience. Their basic proposal is that ethical decision-making is the result of the integration of processesing in three different brain systems: the prefrontal cortex, the temporal lobe, and the limbic system (and/or the reward system). They call this the “event-feature-emotion” complex. In this scheme, PFC computes event-structures (a Grafman term) and social values; the temporal lobe computes perceptual and functional features relevant for social reasoning; and the emotional system computes motive states. An example from the paper illustrates their reasoning. If you come across an orphan child, the “feature” system will inform the brain of the child’s display of sadness, and imbue knowledge of what it means to be helpless. The “event-structure” system will predict the sad future of a child living without parental support, and the “motive” system will activate an emotional response to this cognitive processing. The end result will be something like a complex conceptual and emotional integration: This child is in a state of distress; it will not survive without its parents; this situation makes me sad or angry, and I should do something to help alleviate it. It is the right thing to do.

Moll and Grafman’s model is hardly the last word on ethical decision-making. But it is exciting to see that some progress is being made in understanding how the moral brain works, seeing as the first neuroethics experiment was only published in 2001.

'The Ethical Brain': Mind Over Gray Matter - New York Times

2005-11-03T11:42:00.000+01:00

'The Ethical Brain': Mind Over Gray Matter - New York Times: "

By SALLY SATEL

New York Times

TOM WOLFE was so taken with Michael S. Gazzaniga's ''Social Brain'' that not only did he send Gazzaniga a note calling it the best book on the brain ever written, he had Charlotte Simmons's Nobel Prize-winning neuroscience professor recommend it in class. In ''The Ethical Brain,'' Gazzaniga tries to make the leap from neuroscience to neuroethics and address moral predicaments raised by developments in brain science. The result is stimulating, very readable and at its most edifying when it sticks to science.

As director of the Center of Cognitive Neuroscience at Dartmouth College and indefatigable author of five previous books on the brain for the general reader alone, Gazzaniga is less interested in delivering verdicts on bioethical quandries -- should we clone? tinker with our babies' I.Q.? -- than in untangling how we arrive at moral and ethical judgments in the first place.

Take the issue of raising intelligence by manipulating genes in test-tube embryos. Gazzaniga asks three questions. Is it technically possible to pick out ''intelligence genes''? If so, do those genes alone determine intelligence? And finally, is this kind of manipulation ethical? ''Most people jump to debate the final question,'' he rightly laments, ''without considering the implications of the answers to the first two.'' Gazzaniga's view is that someday it will be possible to tweak personality and intelligence through genetic manipulation. But because personhood is so significantly affected by factors like peer influence and chance, which scientists can't control, we won't be able to make ''designer babies,'' nor, he believes, will we want to.

Or consider what a ''smart pill'' might do to old-fashioned sweat and toil. Gazzaniga isn't especially worried. Neither a smart pill nor genetic manipulation will get you off the hook: enhancement might enable you to grasp connections more easily; still, the fact remains that ''becoming an expert athlete or musician takes hours of practice no matter what else you bring to the task.''

But there are ''public, social'' implications. Imagine basketball stars whose shoes bear the logo not of Nike or Adidas but of Wyeth or Hoffman-La Roche, ''touting the benefits of their neuroenhancing drugs.'' ''If we allow physical enhancements,'' Gazzaniga argues, ''some kind of pharmaceutical arms race would ensue and the whole logic of competition would be neutralized.'' Gazzaniga has no doubt that ''neuroscience will figure out how to tamper'' with neurochemical and genetic processes. But, he says, ''I remain convinced that enhancers that improve motor skills are cheating, while those that help you remember where you put your car keys are fine.''

So where, as Gazzaniga asks, ''do the hard-and-fast facts of neuroscience end, and where does ethics begin?'' In a chapter aptly called ''My Brain Made Me Do It,'' Gazzaniga puts the reader in the jury box in the case of a hypothetical Harry and ''a horrible event.'' This reader confesses impatience with illuminated brain scans routinely used to show that people ''addicted'' to drugs -- or food, sex, the Internet, gambling -- have no control over their behavior. Refreshingly, Gazzaniga declares ''the view of human behavior offered by neuroscience is simply at odds with this idea.''

''Just as optometrists can tell us how much vision a person has (20/20 or 20/40 or 20/200) but cannot tell us when someone is legally blind,'' he continues, ''brain scientists might be able to tell us what someone's mental state or brain condition is but cannot tell us (without being arbitrary) when someone has too little control to be held responsible.''

Last year, when the United States Supreme Court heard arguments against the death penalty for juveniles, the American Medical Association and other health groups, including psychiatrists and psychologists, filed briefs arguing that children should not be treated as adults under the law because in normal brain development the frontal lobe -- the region of the brain that helps curb impulses and conduct moral reasoning -- of an adolescent is still immature. ''Neuroscientists should stay in the lab and let lawyers stay in the courtroom,'' Gazzaniga writes.

Moving on to the provocative concept of ''brain privacy,'' Gazzaniga describes brain fingerprinting -- identifying brain patterns associated with lying -- and cautions that just like conventional polygraph tests, these ''much more complex tests . . . are fraught with uncertainties.'' He also provides perspective on the so-called bias tests increasingly used in social science and the law, like one recently described in a Washington Post Magazine article. Subjects were asked to pair images of black faces with positive or negative words (''wonderful,'' ''nasty''); if they pressed a computer key to pair the black face with a positive word several milliseconds more slowly than they paired it with a negative word, bias was supposed. The unfortunate headline: ''See No Bias: Many Americans believe they are not prejudiced. Now a new test provides powerful evidence that a majority of us really are. Assuming we accept the results, what can we do about it?''

Nonsense, Gazzaniga would say. Human brains make categories based on prior experience or cultural assumptions. This is not sinister, it is normal brain function -- and when experience or assumptions change, response patterns change. ''It appears that a process in the brain makes it likely that people will categorize others on the basis of race,'' he writes. ''Yet this is not the same thing as being racist.'' Nor have split-second reactions like these been convincingly linked to discrimination in the real world. ''Brains are automatic, rule-governed, determined devices, while people are personally responsible agents,'' Gazzaniga says. ''Just as traffic is what happens when physically determined cars interact, responsibility is what happens when people interact.''

Clearly, Gazzaniga is not a member of the handwringer school, like some of his fellow members of the President's Council on Bioethics. At the same time, his faith in our ability to regulate ourselves is touching. He notes that sex selection appears to be producing alarmingly unbalanced ratios of men to women in many countries. ''Tampering with the evolved human fabric is playing with fire,'' he writes. ''Yet I also firmly believe we can handle it. . . . We humans are good at adapting to what works, what is good and beneficial, and, in the end, jettisoning the unwise.''

Gazzaniga looks to the day when neuroethics can derive ''a brain-based philosophy of life.'' But ''The Ethical Brain'' does not always make clear how understanding brain mechanisms can help us deal with hard questions like the status of the embryo or the virtues of prolonging life well over 100 years. And occasionally the book reads as if technical detail has been sacrificed for brevity.

A final, speculative section, ''The Nature of Moral Beliefs and the Concept of Universal Ethics,'' explores whether there is ''an innate human moral sense.'' The theories of evolutionary psychology point out, Gazzaniga notes, that ''moral reasoning is good for human survival,'' and social science has concluded that human societies almost universally share rules against incest and murder while valuing family loyalty and truth telling. ''We must commit ourselves to the view that a universal ethics is possible,'' he concludes. But is such a commitment important if, as his discussion suggests, we are guided by a universal moral compass?

Still, ''The Ethical Brain'' provides us with cautions -- prominent among them that ''neuroscience will never find the brain correlate of responsibility, because that is something we ascribe to humans -- to people -- not to brains. It is a moral value we demand of our fellow, rule-following human beings.'' This statement -- coming as it does from so eminent a neuroscientist -- is a cultural contribution in itself.

Sally Satel is a psychiatrist and resident scholar at the American Enterprise Institute and a co-author of ''One Nation Under Therapy: How the Helping Culture Is Eroding Self-Reliance.''

Taken from NYTimes

Blogging the ethics of neuroscience

2005-11-03T11:41:00.001+01:00

Finally, there is a blog on neuroethics. And it seems that it is not only a buzzword blog: it is initiated by prof. Adam Kolber from the Un. of San Diego School of Law.

As Kolber writes about this blog; "The Neuroethics and Law Blog is an interdisciplinary forum for legal and ethical issues related to the brain and cognition. It is meant to be of interest to bioethicists, legal academics, lawyers, neuroscientists, neurologists, cognitive scientists, psychologists, psychiatrists, philosophers, criminologists, behavioral economists, and others."

So, does that not include the most of us academics dealing with humans? I would think that the top stories from this blog would also make "regular" people discuss.

So what are the latest developments in neuroethics? For formal publications, Martha Farah has just published an article called "Neuroethics: a guide for the perplexed". In here, she touches upon one of the most interesting views in my opinion: if a "naturalist" account of the mind, i.e. conscious and unconscious processes, is correct, it would have a tremendous impact on our self-awareness, and consequences for ethicsa and law.

Another recent development, although many years in the making, is the combination of genetics and neuroimaging techniques. This is indeed a hot topic in human brain mapping science. Of course, it has been known for a long time that genes are the "building blocks" of proteins that e.g. regulate uptake of a certain neurotransmitter. But the new idea is to demonstrate that certain genes that are polymorph, i.e. they have a "natural variation" in healthy individuals, have a significant impact on neural function. Several recent studies by Weinbeger, Hariri and colleagues demonstrate that even among normals, genes can explain different responses of the brain For example, they have shown that individual differences in the response of the amygdala to emotional pictures are explained by their "genetic makeup".

Should we think further from these findings, we might very well end up with people being gene tested for their potential for being cynical soliders, executive and effective business leaders, empathic caregivers ...(fill in your favourite).

Brain cells know more

2005-11-03T11:41:00.000+01:00

A story in NewsWise tells about new research showing that the brain does more than we are aware of. Well, is THAT so surprising? No. We know that in priming studies, words flashed too briefly to be detected, nevertheless influence people's subsequent choices. For example, if the word "king" was flashed below conscious threshold, you would likely choose the word "queen" instead of "farmer" afterwords, even though you were not aware of why you did so.

Anyway, this cited study is still important. It pinpoints brain mechanisms that underlie subliminal perception.

YOUR BRAIN CELLS MAY “KNOW” MORE THAN YOU LET ON BY YOUR BEHAVIOR
http://www.newswise.com/p/articles/view/515337/

Thunderstorm clouds ominously darken the horizon. We nonetheless go out without an umbrella because we are distracted and forget. But do we? Neurobiologists carried out experiments that prove for the first time that the brain remembers, even if we don’t and the umbrella stays behind.

We often make unwise choices although we should know better. Thunderstorm clouds ominously darken the horizon. We nonetheless go out without an umbrella because we are distracted and forget. But do we? Neurobiologists at the Salk Institute for Biological Studies carried out experiments that prove for the first time that the brain remembers, even if we don’t and the umbrella stays behind. They report their findings in the Oct. 20th issue of Neuron.

“For the first time, we can a look at the brain activity of a rhesus monkey and infer what the animal knows,” says lead investigator Thomas D. Albright, director of the Vision Center Laboratory.

First author Adam Messinger, a former graduate student in Albright’s lab and now a post-doctoral researcher at the National Institute of Mental Health in Bethesda, Md. compares it to subliminal knowledge. It is there, even if doesn’t enter our consciousness.

“You know you’ve met the wife of your work colleague but you can’t recall her face,” he gives as an example.

Human memory relies mostly on association; when we try to retrieve information, one thing reminds us of another, which reminds us of yet another, and so on. Naturally, neurobiologists are putting a lot of effort into trying to understand how associative memory works.

One way to study associative memory is to train rhesus monkeys to remember arbitrary pairs of symbols. After being shown the first symbol (i.e. dark clouds) they are presented with two symbols, from which they have to pick the one that has been associated with the initial cue (i.e. umbrella). The reward is a sip of their favorite fruit juice.

“We want the monkeys to behave perfectly on these tests, but one of them made a lot of errors,” recalls Albright. “We wondered what happened in the brain when the monkeys made the wrong choice, although they had apparently learned the right pairing of the symbols.”

So, while the monkeys tried to remember the associations and made their error-prone choices, the scientists observed signals from the nerve cells in a special area of the brain called the "inferior temporal cortex" (ITC). This area is known to be critical for visual pattern recognition and for storage of this type of memory.

When Albright and his team analyzed the activity patterns of brain cells in the ITC, they could trace about a quarter of the activity to the monkey’s behavioral choice. But more than 50 percent of active nerve cells belonged to a novel class of nerve cells or neurons, which the researchers believe represents the memory of the correct pairing of cue and associated symbol. Surprisingly, these brain cells kept firing even when the monkeys picked the wrong symbol.

“In this sense, the cells ‘knew’ more than the monkeys let on in their behavior,” says Albright.

And although behavioral performance is generally accepted to reliably reflect knowledge, in fact, behavior is heavily influenced – in the laboratory and in the real world – by other factors, such as motivation, attention and environmental distractions.

“Thus behavior may vary, but knowledge endures,” concluded Albright, Messinger and their co-authors in their Neuron paper. The other co-authors are Larry R. Squire, a professor in the Department of Psychiatry at the UCSD School of Medicine, and Stuart M. Zola, director of the Yerkes National Primate Research Center in Atlanta.

The Salk Institute for Biological Studies in La Jolla, California, is an independent nonprofit organization dedicated to fundamental discoveries in the life sciences, the improvement of human health and the training of future generations of researchers. Jonas Salk, M.D., whose polio vaccine all but eradicated the crippling disease poliomyelitis in 1955, opened the Institute in 1965 with a gift of land from the City of San Diego and the financial support of the March of Dimes.

© 2005 Newswise. All Rights Reserved.

Free willie --- and implications

2005-11-03T11:40:00.000+01:00

This story dropped in through my Google Alerts the other day (not Dilbert). Are we really going to get any further in explaining free will, whatever that is?

When teaching students and giving talks touching this topic, I often must ask: what is free will free from? We know that as biological beings, we are bound by the physical forces of nature; as social beings our behaviours are constrained by our social milieu. Our choices are influenced by moods and unconscious processes (such as priming). So what to we really mean by "free"?

This article also discusses some of the ethical implications of neuroscience --- yes, neuroethics again-again. Take this as a hint that brain science is beginning to have an impact on human thought and introspection, even everyday thought and talk.

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Does Neuroscience Refute Free Will?

This is the excellent foppery of the world, that, when we are sick in fortune, — often the surfeit of our own behavior, — we make guilty of our disasters the sun, the moon, and the stars; as if we were villains on necessity, fools by heavenly compulsion, knaves, thieves, and treachers by spherical predominance, drunkards, liars, and adulterers by an enforc'd obedience of planetary influence, and all that we are evil in, by a divine thrusting on. --William Shakespeare

In the above quote from King Lear we find a description of those who, throughout human history, deny free will and personal responsibility, instead blaming their wrongdoings on interventions divine and planetary. In a recent article, Joshua Greene and Jonathan Cohen join the believers in the "divine thrusting on."[1] This being the scientific age, and our authors being card-carrying neuroscientists, the divine thrusting on becomes a neuroscientific thrusting on, the brain playing the role of the stars above.

The divine thrust of their argument is that we have no free will because there is neuroscience, though our laws have yet to take this into account:

… the law's intuitive support is ultimately grounded in a metaphysically overambitious, libertarian notion of free will that is threatened by determinism and, more pointedly, by forthcoming cognitive neuroscience…. The net effect of this influx of scientific information will be a rejection of free will as it is ordinarily conceived, with important ramifications for the law.[2]

What are these ramifications? To begin with, the concept of personal responsibility is obsolete. Since all actions are determined by the "preexisting state of the universe," we have no choice in the matter. As they put it: "Given a set of prior conditions in the universe and a set of physical laws that completely govern the way the universe evolves, there is only one way that things can actually proceed." Thus we can logically trace everything back to the Big Bang that blasted the universe into existence. Should you ask why I had bagels rather than bananas for breakfast this morning, for example, I can refer you to the Big Bang theory of human action.

But if there is already the Big Bang, why do we need neuroscience to reveal our lack of free will? According to Greene and Cohen, for ages "scientific" philosophers, i.e. philosophers of their determinist camp, had argued against free will, but because the mind was then a black box, it was easy for the deluded religious people, the soft humanists, and other dim-witted souls to cling to the illusion of free will.

Now that we have neuroscience, however, the mind is a black box no more — it is high time for the rest of us to wake up from our dogmatic slumber and smell the deterministic universe. In short, while the Big Bang provides the big picture, neuroscience supplies the details, which will make it abundantly clear, even to the lay public, that we are literally puppets in a deterministic universe after all.

Blame it on the brain
Greene and Cohen argue that our brains are responsible for all our behaviors. Our "brains" commit crimes. "We" are innocent. Thus, in their words, "demonstrating that there is a brain basis for adolescents' misdeeds allows us to blame adolescents' brains instead of the adolescents themselves." It is fortunate that the boys in the neighborhood have not read their article, for here is their new defense after damaging your property: I didn't do it, it was my brain!

Although it has been known even before Plato that the brain plays a central role in behavior, this particular argument is rather novel. One reason others have not been bold enough to advance it (despite a perennially strong demand for determinism) is that it contains a glaring category error. Greene and Cohen compare two opposing sources of agency — either your brain or you — as if they are mutually exclusive, as if without your brain you would still be a moral agent.

As a result of this error, Greene and Cohen conclude, "the idea of distinguishing the truly, deeply guilty from those who are merely victims of neuronal circumstances will, we submit, seem pointless."

But the moral agent in the legal sense is the whole package — you consisting of your brain and the rest. To say that we are victims of neuronal circumstances is to say that we are victims of ourselves. The underlying assumption is that we have no control over "neuronal circumstances," just as we have no control over "external circumstances." But this assumption (a newly bottled behaviorist assumption) entirely contradicts our knowledge that the brain is a self-organizing and self-regulating biological system, not merely a step in the transformation of some external stimulus to behavioral output.

It is, however, not necessary to discuss in any detail the brain as a control system in order to refute Greene and Cohen, for their argument is not based on any understanding of the brain at all. It boils down to the primitive logic that, for example, if I stole your wallet then my hand is to be chopped off.

Mr. Puppet
To their credit, Greene and Cohen sensed that blaming everything on the brain is not enough. They have another weapon in store for free will, yet another "thought experiment." For their strategy is to generate as many arguments as they can against free will, hoping that some of them will have done the damage, even if these arguments contradict each other.

In their second strike, they urge us to imagine the case of a "Mr. Puppet," a criminal designed by a group of scientists through tight genetic and environmental control. During Mr. Puppet's trial, the lead scientist is called to the stand by the defense. And here is what Greene and Cohen had him say:

I designed him. I carefully selected every gene in his body and carefully scripted every significant event in his life so that he would become precisely what he is today. I selected his mother knowing that she would let him cry for hours and hours before picking him up. I carefully selected each of his relatives, teachers, friends,enemies, etc., and told them exactly what to say to him and how to treat him. Things generally went as planned, but not always. For example, the angry letters written to his dead father were not supposed to appear until he was fourteen, but by the end of his thirteenth year he had already written four of them. In retrospect I think this was because of a handful of substitution I made to his eighth chromosome.

Of course, a change in the chromosome cannot determine the timing of a nasty letter written, since the genome does not contain information that specifies any of our actions. The environmental regulation, too, is impossible, except in science fiction. But plausibility or knowledge of basic biology is not to be expected from our authors. Greene and Cohen believe that Mr. Puppet is not responsible for his actions, because "forces beyond his control played a dominant role in causing him to commit the crimes, it is hard to think of him as anything more than a pawn."

But even if we assume, for the sake of argument, that such a person could be so designed, we might conclude that he is indeed a puppet of the scientist-designer, while we are not puppets of this sort. Our genes are not selected, nor our environment scripted, by anyone.

Not surprisingly, however, Greene and Cohen reach a rather different conclusion:

What is the difference between Mr. Puppet and anyone else accused of a crime? After all, we have little reason to doubt that (i) the state of the universe 10,000 years ago, (ii) the laws of physics, and (iii) the outcomes of random quantum mechanical events are together sufficient to determine everything that happens nowadays, including our own actions. These things are all clearly beyond our control. So what is the real difference between us and Mr. Puppet? … in a very real sense, we are all puppets. The combined effects of genes and environment determine all of our actions. Mr. Puppet is exceptional only in that the intentions of other humans lie behind his genes and environment. But, so long as his genes and environment are intrinsically comparable to those of ordinary people, this does not really matter. We are no more free than he is.

In an apparent slip, they acknowledged that the scientists had intentions, that they deliberately acted in designing Mr. Puppet. Their actions apparently differ from causes that are not human actions. Greene and Cohen never bothered to ask whether these scientists ought to be punished for specifically designed someone to commit crimes, whether they are responsible at all. But if we are forced to accept this scenario, then the responsibility for the crimes appears to lie with the scientists — for designing puppet criminals.

According to Green and Cohen, however, Mr. Puppet's genes and environment are "intrinsically comparable" to those of ordinary people, as if we all live in a designed environment, in which people deliberately abuse us and lie to us; as if our genes, rather than the results of natural selection, are picked by a team of evil scientists. Intrinsically comparable? By that they presumably mean that the environment is still a earthly environment like ours, the same house with furniture and TV and parents, and so on, and the genes are still stretches of DNA made up of garden-variety nucleotides.

But clearly these "intrinsic" features are irrelevant in Mr. Puppet's case. His genes and environment, after all, are designed to make him a criminal. But note, in particular, Greene and Cohen's peculiar emphasis on the combination of genes and environment. Biology, of courses, tells us there are additional factors which are neither genetic nor environmental, but we can safely assume that these authors, possessing no particular interest in the science of biology, are not aware of these.

Being metaphorical scientists, by "genes and environment" they mean everything that makes us who we are, everything that determines our actions. We are now ready to translate their claim into plain English: Everything that determines who we are determines who we are; everything that determines our actions determines our actions. Surely we do not have control over everything — Greene and Cohen correctly assume. And surely all possible factors combined determine our actions. But while reaching such a brilliant conclusion they have spun their minds out of control, ignoring the circularity in the process. We are compelled by the laws of logic to agree with them: Yes, a banana is a banana.

Illusion of free will
Having thus disposed of free will, Greene and Cohen are ready to explain why we think we have such a thing. If we think we have something that doesn't exist, then that something must be an illusion. Hence their claim that the brain generates the illusion of free will to fool us into thinking we are in control.

With becoming modesty, our authors compare themselves to Copernicus, Darwin, and Freud in overthrowing human narcissism. Copernicus removes the earth as the center of the universe, Darwin removes human beings as lords of the earth, and Freud removes consciousness as the sole determinant of human behavior. Here comes another blow beneath the belt — even what little conscious control you have over your action is an illusion.

It seems to me, however, that this is a case of sadomasochism. Green and Cohen appear to derive keen delight out of wounding human narcissism, as represented by free-will folk psychology. You thought you decided to read this article because it seemed interesting. But no, you have no clue, and that thought was really just some illusion generated by your brain to mask its cluelessness.

How much insult to your narcissism can you take? That is the question, on which your scientistic manhood depends. Only tough scientists like Greene and Cohen are brave enough to take determinism straight, without illusions. And if you don't think you are a puppet yet, they will beat you into submission with their thought experiments and imagined data until you give up your selfhood. And so the game goes on.

Although I do not wish to deny the multitudinous pleasures derived by Greene and Cohen from becoming puppets of metaphysical fiction and mouthpieces of pseudoscientific rant, I do wish to examine the evidence they present for their claims.

For such evidence Greene and Cohen rely on the work of Daniel Wegner,[3] a Harvard psychologist and a fellow metaphorical scientist. According to Wegner, our actions are not caused by our willing. In support of this claim he cites evidence that hypnosis or brain damage can impair our sense of free will, that various experimental manipulations can create in us the illusion of control.

Our immediate response is: So what? We will not have free will if our heads are cut off. We will not have free will if we are asleep. Sometimes we erroneously thought we caused something to occur when, in fact, we did not. From this, however, it does not follow that free will is an illusion.

Under hypnosis, for example, we might feel that our arm was raised even though we did not will it. Likewise, when our motor cortex or our muscle is stimulated, various movements might be induced which are not willed. For Wegner, however, this sense of "it just happens" is a more accurate description of what really happens when we act. It never occurred to him that there is no experience of will because these are not instances of voluntary actions under our control.

Wegner very much prefers this sense of passivity, for only then do we feel like inanimate objects. When my arm uncontrollably does something, it is acting as a "scientific object" should, like a brick. Our free will must be an illusion because it does not fit into Wegner's scientific understanding of the world.

The philosopher Daniel Dennett believes that, for the sake of convenience, we adopt the "intentional stance" when interpreting the behavior of other human beings. Wegner's position can be described as the "passivity stance." He prefers to feel like the hypnotic subject, the brain damaged patient, or a zombie in general, because, according to his scientific Weltanschauung, the passivity stance is a more accurate reflection of reality. But the question remains as to whether Wegner, or the average man on the street, is actually delusional.

Agreeing with Wegner's claim that our sense of free will is an illusion, Greene and Cohen go one step further, and argue that our attribution of free will in others is also an illusion.

They cite a study by Heberlein et al., who presented the following film to human subjects: a big triangle chases a little circle around the screen, bumping into it. The little circle repeatedly moves away, and a little triangle repeatedly moves in between the circle and the big triangle. When normal people watch this movie they see these interactions in social and intentional terms. The big triangle tries to harm the little circle, and the little triangle tries to protect the little circle.

However, a patient with damage to the amygdala, an almond-shaped collection of different brain structures, fails to see these shapes in such intentional terms.[4] Consequently, for Greene and Cohen, because this attribution of free will is generated by a brain area, it is also an illusion.

Readers of my earlier article will be familiar with Greene and Cohen's penchant for evolutionary speculation. Here they go again. According to their new so-so story, parts of the brain, in the course of evolution, become specialized modules for folk psychology, e.g. attributing free will to others; other parts, for folk physics, e.g. believing in the sort of motion typically seen in a Disney cartoon. We know that folk physics is wrong, but folk psychology is just as wrong, according to Greene and Cohen. Because of our folk psychology system, we think of other animate objects as uncaused causers. But after learning neuroscience, "when we look at people as physical systems, we cannot see them as any more blameworthy or praiseworthy than bricks."

Perhaps we could posit, in addition to the folk physics system and the folk psychology system, a third system of masochistic scientism, which fools one into believing one is a brick being acted on by the forces of nature, rather than an acting agent responsible for his actions. The neural basis of this third system, I submit, remains to be established.

To summarize then, our brick-minded theorists accuse folk psychology behind the law to view moral agents as uncaused causers. Since we are not uncaused causers, we cannot be moral agents, and we cannot be responsible for our actions.

Now if I am an uncaused causer, my actions are insulated from any external influence. Suppose a man is given a life sentence for killing the guard while robbing a bank, such a punishment cannot possibly prevent me from doing the same. Deterrence is indeed impossible if I am the uncaused causer of my actions.

However, this cannot possibly be the assumption behind our law, because it cannot possibly explain the law's focus on intentionality. According to the folk psychology that Greene and Cohen attack relentlessly, it is characteristically human that we deliberately choose appropriate means to reach desired ends. This capacity enables us to become moral agents, the targets of praise or blame. For example, an act is not guilty lest there be a guilty mind (Reum non facit nisi mens rea).

As Mises repeatedly pointed out, the very concept of human action, of means and ends, presupposes the category of causality. Responsibility does not imply that we are unmoved movers in the Aristotelian sense, standing outside of the chain of cause and effect, but that we, as agents of intentional actions, are in a peculiar position in a long chain of causes stretching back to the Big Bang. We are agents capable of controlling our actions, not reflex-arcs translating stimulus into response.

The law, then punishes crimes that are the result of deliberation and willing, and is lenient towards accidents or those agents incapable of rational actions (e.g. children). This selectivity can only be based on the idea of deterrence. For it would be absurd to tell someone not to murder, if he could not help it, just as it is absurd to tell someone to stop beating his heart.

The law, instead, punishes crimes that result from actions that we can control, and could thus prevent such actions in the future.

If the law is in fact based on the assumption of uncaused causers, it would have no reason to make distinctions between deliberate murdering and accidental killing. Strict liability would apply to all crimes. It is of course beyond the scope of this article to discuss the history of the law, though it should be pointed out that the concept of personal responsibility in violent crimes is in fact a relatively recent development. Strict liability, extending to relatives and Lords, is common in many primitive societies (I refer the interested reader to Pollack and Maitland's masterpiece or Zane's book on the history of law).

Law and liberty
Free will, in the sense discussed here, means that humans control what they do. Neuroscience will not change this fact. Science fiction, of the variety favored by Greene and Cohen, could always imagine such a day. In this sense, it cannot be distinguished from any teleological religion.

Indeed, determinism of this type, which claims that human beings do not choose, do not act, but are always acted upon, has been revived innumerable times in history, in various guises. It is a historical fact that primitive savages, religious fanatics, and believers in inexorable laws of history have always advocated some version of it.

In the development of the law also, the concept of personal responsibility evolved, partly because some human beings, after struggling free from superstition and the "passive stance," began to understand the nature of their own actions and their effects on the world. Enlightened individualism, we should remember, was a late development, and remains unpopular in many parts of the world today. The intuitive folk psychology of human action we possess is the product of such enlightenment.

On the other hand, in attacking the concept of free will and personal responsibility, Green and Cohen merely revive the cult of irrational thought that has long prevailed in human societies. It should not therefore surprise us to find in their article the following sentence: "rationality is just a presumed correlate of what most people really care about." Indeed, what is left of rationality when you are not responsible for your actions?

In place of reason, these authors substitute aggregate welfare. The law reformed in light of neuroscientific knowledge should, according to them, aim to promote future welfare, rather than punish those responsible for their crimes. In an earlier article I discussed the attempt by these authors to abolish universal moral norms using brain imaging data, in the name of aggregate welfare. We should at least applaud their consistency. Of course, a universal moral norm such as the Categorical Imperative would have no meaning if there is no free will. Why tell someone not to steal if he could not help it, if his brain was to blame?

All considered, then, their arguments boil down to this: (1) the criminal is not responsible for his crime because everything that determines who he is determines who he is; (2) instead of punishing criminals for what they deserve, the law should maximize future welfare.

Ethically, it seems preposterous to argue against the total welfare of mankind, just as logically, it is impossible to refute a tautology. The take-home lesson here is that you should always watch out for someone who argues for something that cannot possibly be contradicted, for there is often a hidden agenda, attached to the can't-possibly-be-wrong package, that triggers the self-destruction of the whole thing once uncovered.

As I pointed out in the earlier article, their concept of aggregate welfare is a vacuous concept, made up for the sake of convenience. We cannot possibly calculate what this welfare is, though we can indirectly observe, by studying history, the long-term effects of certain rules and practices on groups that follow them. In the latter, somewhat more concrete sense of welfare, our current legal framework appears to have been one of the chief promoters of human welfare, judging by the remarkable spread of the relevant ideas from the West, against often strong resistance from local customs and primitive practices.
What we can and cannot know: $16
Finally, throughout their essay, Greene and Cohen emphasize that the "libertarian" conception of free will which they attack has no connection to the political philosophy. This disclaimer, however, betrays ignorance of the political philosophy. Free will and responsibility provide the necessary foundation of the libertarian political philosophy. Laws protect liberty, and liberty entails responsibility.

Their arguments for determinism are yet another attempt to abolish laws as abstract rules that apply to everyone equally. Instead the State and its "scientific experts" will get to decide whether a person will be harmful to society or not, in order to maximize future welfare in each case (i.e. to do whatever those in power wish to do). The law itself becomes meaningless. And instead of being general rules that protect individual liberty, in the hands of Greene and Cohen, and in the name of neuroscience, it will be used, as a tool for state intervention and arbitrary judgments, to destroy liberty.

Lucretius is a neurobiologist living in Maryland. Email. He will read the blog and answer comments there. Read his first article: Does Neuroscience Refute Ethics?

1. Greene, J. & Cohen, J. "For the law, neuroscience changes nothing and everything." Philos Trans R Soc Lond B Biol Sci 359, 1775-85 (2004).

2. von Mises, L. Theory and History (Mises Institute, 1957).

3. Wegner, D. M. Precis of the illusion of conscious will. Behav Brain Sci 27, 649-59; discussion 659-92 (2004).

4. Heberlein, A. S. & Adolphs, R. Impaired spontaneous anthropomorphizing despite intact perception and social knowledge. Proc Natl Acad Sci U S A 101, 7487-91 (2004).