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Picture 1Here is a heads up for a recent study demonstrating – again – that the amygdala is not merely a “fear centre” in the brain. I have previously blogged about the amygdala, first not being a single structure, and that it is not only involved in fear.

In 2007, a team of French researchers demonstrated that direct stimulation of the amygdala did evoke emotional responses, but that there was a difference between which hemisphere was stimulated. Right amygdala stimulations induced aversive responses, in particular fear and sadness. In contrast, left hemisphere stimulation induced either positive (happiness) or negative emotions (fear, anxiety, sadness). As the abstract reads:

Very few studies in humans have quantified the effect obtained after direct electrical stimulation of the amygdala, in terms of both emotional and physiological responses. We tested patients with drug-resistant partial epilepsies who were explored with intracerebral electrodes in the setting of presurgical evaluation. We assessed the effects of direct electric stimulations in either the right or the left amygdala on verbally self-reported emotions (Izard scale) and on psychophysiological markers of emotions by recording skin conductance responses (SCRs) and by measuring the electromyographic responses of the corrugator supercilii (EMGc). According to responses on Izard scales, electrical stimulations of the right amygdala induced negative emotions, especially fear and sadness. In contrast, stimulations of the left amygdala were able to induce either pleasant (happiness) or unpleasant (fear, anxiety, sadness) emotions. Unpleasant states induced by electrical stimulations were accompanied by an increase in EMGc activity. In addition, when emotional changes were reported after electrical stimulation, SCR amplitude for the positively valenced emotions was larger than for the negative ones. These findings provide direct in vivo evidence that the human amygdala is involved in emotional experiences and strengthen the hypothesis of a functional asymmetry of the amygdala for valence and arousal processing.

Interestingly, there is more to say about this study. First, it may be that there is a systematic bias introduced by the way the researchers did the study. By using high-frequency (50 Hz) stimulation in 1 second, they might have induced one characteristic response of the amygdala. This structure is often seen as having quick “on-off” responses. Thus, one second pulse trains is actually a long duration for the amygdala. So a pulse of 20 milliseconds could be hypothesised to produce different responses. Also, the researchers found that GSR responses were actually larger for positive emotions, when they were reported. As the amygdala has often been implicated in unconscious emotional responses (mostly aversive responses) one may speculate that the left-hemisphere amygdala involvement in positive emotions may be related to conscious emotions.

As always, new findings leads to numerous novel questions, ideas and hypotheses. Which is why science is so much fun. But it is important to note the change we see today the role of the amygdala in emotional responses. We are moving away from the LeDouxian paradigmatic focus on fear (and some aversion)as the sole emotion of the brain, and more towards a balanced view towards a similar focus on positive emotions and (hopefully) more complex human emotions. Through this development, we can see that novel findings are breaking down the old ideas of neo-phrenology, breaking single structures into smaller parts, and into parts of a larger network of convergence and divergence structures. Keep your eyes open, more is on the way.

-Thomas

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Just noticed this very attractive title by the Brafman brothers- The book, Sway — the irresistable pull of irrational behavior, “will challenge your every thought”, according to a NY Times review. And it gets similarly good reviews from other prominent people, like Michael Shermer, the author of the recent book The mind of the market, which I blogged about recently.

I found a couple of good videos on this book that’s good to share:

A longer version with more nuances can be seen here:

So after this, you get the idea: unconscious, automatic thought patterns act out and cause irrational behaviours, sometimes at the worst possible time and place.The questions raised are, of course, interesting and important. Why do we sometimes make horrific decisions, despite having all the information available to make better ones? Why do prominent people, like George W. Bush, suffer from loss aversion, leading to billions of dollars spent and thousands of lives lost? Because it’s “too late” to pull out? Because the pain of acknowledging defeat, error or insufficiency is bigger than the benefit of sparing yet more money and lives?

Other examples can be found at the Wall Street, military, aircraft captains, and even yourself. Maybe even on a daily basis. Taken together, the examples presented in these videos and the book demonstrate that we are all susceptible to make these kinds of errors. The next and better step is, of course, to identify these errors in ourselves (and others) and act upon them in time. Coaching, anyone?

I guess I should read the book, if the publishers will send me the book 8)

-Thomas

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Here is a heads up for the upcoming Sedbergh Festival of Ideas. Martin is going over to bring our view on the neuroethics of consciousness science research. Unfortunately, I’m unable to attend, but Martin will cover our ideas very nicely.

The event Martin is talking at is “Event 4 — Varieties of consciousness“, together wih no other than Geraint Rees, Ilona Roth and Max Velmans. If you are in the vicinity, why not attend? I hope Martin is going to blog about this meeting, just as he will with his recent trip to the HBM conference.

UPDATE: Here is the program (I just received from Andi Chapple):

Session 1 – Science and Consciousness
10am – 1.30pm, Saturday 19 July
People’s Hall, Howgill Lane, Sedbergh, Cumbria LA10 5DE, England
£15 (£6 concessions) for the whole session, £6 (£2.50 concessions) for the discussion (introduced and moderated by Prof. Velmans) from 11.45am to 1.30pm.

Professor Geraint Rees, Institute of Cognitive Neuroscience, UCL, London
Dr. Ilona Roth, Psychology in Science Group, Open University
Martin Skov, Danish Research Centre for Magnetic Resonance, Copenhagen
Professor Max Velmans, Goldsmiths College, London

Professor Tom Ormerod, University of Lancaster introduces the speakers.

Session 2 – Varieties of Consciousness
10am – 1.30pm, Sunday 20 July
People’s Hall, Howgill Lane, Sedbergh, Cumbria LA10 5DE, England
£12 (£5 concessions)

Speakers will lead short hands-on sessions so the audience can get personal experience of what they are talking about, then present their area of interest, and then there will be a general discussion.

Dr. Michael Daniels, Liverpool John Moores University (transpersonal
psychology and parapsychology)

Dr. David Scott (Zen and ‘Big Mind’ techniques)
Ian McPherson (t’ai chi and qi gong)

-Thomas

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hjernep1grafik620×120_istoc.jpg

And while we’re in the talk of media coverage, I should mention to those who understand Danish that the Danish Broadcast Company, or DR, has a documentary series on their primary radio channels, P1. The series is called “Hjernerejsen” (loosely translated to “The brain travel”) and it covers topics such as emotions and bonding, brain maturation, transhumanism and neuroethics.In the program called “the soul is in the brain”, I starred in an interview about the new ideas that neuroscience brings to our traditional thoughts about personality and self. My co-interviewees were Jesper Mogensen and Albert Gjedde, both well-renowned neuroscientists both within and outside Scandinavia.

In a coming topic on the senses (tomorrow, April 19.), I speak about how neuroscience can be used in marketing, aka neuromarketing.

The series can be found here, and DR does a nice podcast: http://podcast.dr.dk/p1/rssfeed/tema_torsdag.xml (copy and paste into your preferred podcasting program)

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books.jpgWhile Thomas is getting his kicks off at the SfN meeting in Atlanta I am toiling away at a number of long overdue papers here in the increasingly cold Denmark. I have several longer blog posts planned, but no time to write them. So, here’s three things to read in the meantime at other venues on the net.

First, John Searle reviews a new book on consciousness by Nicholas Humphrey, Seeing Red, in The New York Review of Books. I have always enjoyed Humphrey’s work, but his new theory on consciousness sounds plain weird (at least as retold by Searle; I haven’t read Humphrey’s book). In Searle’s words:

(more…)

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scr11_new.pngThis time it should work. Science & Consciousness Review, the online webzine/journal for the review of the scientific study of consciousness, is back online. It crashed several months ago due to a buggy new interface and content management system. Now, with a fresh new and well proved system (same as BrainEthics is using, wordpress), it is now running, albeit in a next-to-full version. Commenting is still disabled, as are newsletters, certain images and some other functions. It’s slowly coming up, too
However, you can now enjoy the articles that we at BrainEthics have contributed with at SCR. First of all, Martin’s excellent review of Solso’s book on neuroaesthetics, and my article on “how genes make up your mind”.

Enjoy… and spread the word.

-Thomas

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A conscious veggie?

lockedin.jpgIt should be mentioned that there is a highly controversial paper out in this week’s Science. Here, a study by Dr Adrian Owen shows that a patient that meets the criteria for vegetative state shows what can be thought of as signs of conscious life. You can see the MindHacks coverage of this story here. basically, the researchers asked their patient to imagine playing tennis or moving around her home and found that:

the patient activated predicted cortical areas in a manner indistinguishable from that of healthy volunteers

The researchers take this as a sign of the patient being conscious while still being unable to communicate, let alone perform any volutary behaviour. In this sense, it seems that the patient rather meets the criteria for locked-in syndrome. The study thus raises the question of whether this patient — indeed, any PVS patient — is conscious, and whether the diagnostic criteria are yet poorly defined and the symptoms similarly poorly understood.

Nevertheless, it should be considered an open question whether we should accept this finding as a true sign of consciousness in the patient. This is also covered nicely in a comment by Naccache in the same issue of Science. Pointing out some of the shortcomings of this study, as well as contrasting it to the many studies showing specific changes in PVS contrasted to normal consciousness, Naccache concludes:

Though not totally convincing on the issue of consciousness, the Owen et al. work paves the way for future functional brain-imaging studies on comatose and vegetative state patients. One can imagine probing each of the psychological properties of conscious processing listed above, and even trying to collect subjective reports by modifying the experimental paradigm.

As I have written earlier, this is indeed the case: we do not have a clear concept of the distinctions between coma, vegetative states, minimally conscious states or locked-in syndrome. Only during the past few years we have seen a dramatic increase in our understanding of these disorders. It is no doubt that our understanding will increase in the same manner during the next many years.

I have asked Dr. Owen and his co-author, Steven Laureys about this finding, and hope to get back to you with their replies shortly. In the meantime, you might be interested in this article (PDF) that Laureys and I co-authored with prof. Bernard Baars in TINS.

UPDATE: Nature has a podcast interview with Dr. Owen here.

-Thomas

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