Wednesday, February 18, 2009

Encephalon - 64th Edition

Welcome to the Sixty-Fourth Edition of Encephalon, a neuroscience and psychology blog carnival. I’d be lying if I told you I didn’t procrastinate just a bit on writing this post… I was hoping that a “Darwinian Presidential Valentine Encephalon for Paraskavedekatriaphobics” theme might emerge from the large number of submissions, but it did not. So without further ado, let us tally no longer, onward and upward..... hey, stop procrastinating!


Doctor Spurt at Effortless Incitement advises us to be concrete in order to achieve a distant goal in Construal Level and Procrastination. Construal-level theory holds that “events that are distant in time tend to be represented more abstractly than are events that are close in time.” To test how this idea might relate to procrastination, McCrea et al. (2008) distributed questionnaires to be returned at a later date. Those with questions that were framed in more abstract terms (e.g., “what characteristics are implied by opening a bank account?”) were returned at a more laggardly rate than those with more concrete requirements (“how do you go about opening a bank account?”).

Would I lie to you about lie detection? Kylie Sturgess from PodBlack Cat reviews the new TV show, Lie To Me, and likes what she sees so far:
Right now I’m watching the second episode, where it begins with lie detectors and how they’re little better than holding a West African Egg.

In West Africa anyone suspected of a crime was made to hand a bird’s egg to another person. Anyone who broke the egg would be considered guilty, based on their nervousness.

In ancient China suspects were told to hold a handful of rice in their mouths during a prosecutor’s argument. The suspect was considered guilty if, by the end of that argument, the rice stayed dry — because salivation was believed to cease in times of anxiety.

And all bogus as a lie detector.

Speaking of lying and reviews, individuals with autism spectrum disorders (ASD) are notoriously incapable of detecting deceit from another person’s facial expression, body language, or tone of voice. They are also unlikely to deceive other people, although some with ASD (autistic savants) show remarkable abilities in other realms. Arj from ** Science On Tap ** reviews Daniel Tammet’s new book:

Autistic savant Daniel Tammet's first book, "Born On A Blue Day" was an international best-seller as an engaging autobiographical overview of his fascinating life and talents. His new book, "Embracing The Wide Sky" is a more scientific look at the way his mind works, and provocatively covers a range of cognitive issues. Tammet's perspective is utterly unique, as an articulate, thoughtful savant who can introspectively analyze his own mind workings.

Synesthesia, a "neurologically based phenomenon in which stimulation of one sensory or cognitive pathway leads to automatic, involuntary experiences in a second sensory or cognitive pathway," is not uncommon in people with ASD. Tammet discusses his own synesthesic percepts, which include numbers that have color and texture, or shape. Mo from Neurophilosophy discusses a new study establishing that synesthesia has a genetic component. Prior research assumed that the condition might be X-linked (because it affects more females than males) and transmitted by a single gene. But the truth is more complex, as usual:

Researchers from the University of Oxford have now conducted the first genome-wide search for genes linked to the condition. In the American Journal of Human Genetics, they report the identification of a number of genes that are likely to be involved in auditory-visual synaesthesia, in which sounds are perceived as colours. The study reveals also that synaesthesia is not X-linked, and that the genetics of this form of synaesthesia - and probably that of other forms - is far more complex than previously thought.
(Image Credit: Jane Mackay)


Jane Mackay painted “Tchaikovsky’s First Piano Concerto” to create a synesthetic composition that bridges the gap between sight and sound. [from Yale Scientific Magazine]

Interestingly, one of the chromosomal regions identified in the Oxford study contains a gene associated with autism. Sandeep Gautam from The Mouse Trap has written about the existence of a continuum between autism and schizophenia in the past. A "dueling parental genes" version of this hypothesis was featured in a Nature essay last year and received coverage in the New York Times. Sandy’s current submission covers Psychosis and Salience dysregulation. According to this view, the neurotransmitter dopamine is involved in assigning salience and motivational significance to internal and external events. Excessive dopamine release in schizophrenia can result in an aberrant emphasis on internal representations (thoughts, perceptions, memories) relative to external sensory stimuli in the environment. Jim van Os goes even further, arguing for the end of “schizophrenia” as a diagnostic entity and the beginning of “salience dysregulation syndrome.” Most would agree that that the DSM-IV label “schizophrenia” can refer to quite different disorders. However, this new scheme suffers from its own categorical limitations (in my opinion) because salience dysregulation syndrome (van Os, 2009) can manifest...

with affective expression (high in mania/depression dimension); with developmental expression (high in developmental cognitive deficit/negative symptoms); and not otherwise specified.

...depending on whether certain “thresholds” for the various dimensional components are exceeded.

But dopamine can be fun too! Yay! But not for the mouse that couldn't get high. Boo. At Neurotopia, Scicurious comments on the latest paper about the dopamine transporter knockout mouse (DAT-KO) and the rewarding and reinforcing effects of cocaine. DAT recycles dopamine (DA) from the synapse back into the neuron, so the DAT-KO mice have an excess of DA hanging around their synapses. However, earlier studies found that DAT-KO mice did self-administer cocaine…gasp!
If cocaine was rewarding WITHOUT increasing DA levels in the brain, the dopamine theory of addiction was wrong, and a bunch of scientists were going to have to stop going to things like "dopamine dinners" and "the international conference on dopamine".
The current crop of DAT-KO mice was different, although it’s not clear why. Could it be that different stem cells were used to create each mouse line?? I’m going to the next “dopamine dinner” to find out.

Ward Plunet of Brain Health Hacks asks, Do antidepressant work just because they make you hungry? What he really should have asked is "Do antipsychotics work just because they make you hungry?", because the drugs in question include olanzapine (Zyprexa) and clozapine (Clozaril), which are atypical antipsychotics. These are well-known for causing significant weight gain, and one mechanism for this might involve increases in ghrelin, a hormone that stimulates appetite. Many of the atypicals are already in use for treating bipolar disorder, but they are not at all typical (yet) for unipolar depression. In November 2007, the FDA approved aripiprazole (Abilify) as an add-on medication for unremitting depression (meaning, the patients were already taking an antidepressant drug but were still depressed).

Moving into the topic of conventional antidepressant drugs, one proposed mechanism of action is through neurogenesis, or the growth of new neurons, in the hippocampal region of the medial temporal lobe (specifically, the dentate gyrus field). Andy from BrainsLab.net discusses the enhancement of neurogenesis in adulthood resulting from exposure to an enriched environment. Another route to increased neurogenesis involves conditioned responses in hippocampal-dependent learning tasks. Since the hippocampus is a critical for learning and memory, do these new neurons contribute to an improvement in these tasks? That does seem to be the case.

But is altered neuroplasticity a cause or an effect of major depression? Although neurogenesis has been seen as the “next new thing” to explain the efficacy of antidepressant drugs, this view is not without controversy. Another proposed contributor to the etiology of mood disorders (especially bipolar disorder and seasonal affective disorder) is dysregulation of circadian rhythms. For an overview, Lithium, Circadian Clocks and Bipolar Disorder (and anything else on the subject by Coturnix of A Blog Around The Clock fame) is a good place to start. One current submission from Amiya Sarkar (of Physiology Physics Woven Fine) reviews the Molecular Basis of Genetic Switch In The Circadian Clock.

Continuing with the general theme of mental health, Sandra Kiume presents Suicide Hashtag Livetweeting. A recent suicide standoff and the mediated reactions of people on Twitter are analyzed for the World of Psychology blog. The post includes a Twitter glossary, and the launch of a new resource for people in distress seeking crisis resources and information: the #unsuicide hashtag.

February 12 was the 200th birthday of Abraham Lincoln, the great U.S. president who ended slavery. The Neurocritic (courtesy of Channel N) featured a President's Day video on Lincoln's battle with depression, produced by John McManamy. For more background, read the detailed biography Lincoln's Melancholy by Joshua Wolf Shenk.

February 12 also marked the 200th birthday of Charles Darwin, father of the theory of evolution by natural selection. We all know that acquired traits cannot be inherited, right? Two of our contributors tackle a recent paper that potentially raises a thorny exception to the rule (at least, if you believe the simplistic popular coverage of the finding, which you should not).

First up is John Fossella of Genes to Brains to Mental Health, who wishes a Happy 200th birthday Charles Darwin ! Here’s an inherited acquired characteristic for you:
[Arai et al., 2009] measured a trait known as long-term potentiation (LTP), wherein a synapse fires in a longer and stronger fashion. This type of potentiation is thought to be a basic mechanism that neural networks use in learning and memory formation. In their paper, the team found that certain synapses in the hippocampus were potentiated when animals were exposed to an “enriched” environment (normally mice are caged in empty bins lined with woodchips, but an enriched environment is one filled with tunnels, hidden passages, toys, ropes to climb & other stuff to discover and learn about). The team shows that, in response to an enriched environment, the mice acquire the LTP trait.

The next thing the team found was that the offspring of female (but not male) mice that had acquired the LTP trait - did also show the LTP trait - even when they, themselves, did not experience the enriched environment. Thus, the so-called acquired trait (LTP) was inherited by the offspring. Hmmmm - sounds a bit Lamarckian to me, or, as the authors of this research article suggest, “Lamarckian-like”. Is this a case that violates core tenets of the modern synthesis ? Does it besmirch Darwin on his 200th birthday ?
NO!! Find out why not by reading the rest of the post.

In addition, Robert Sylwester from SharpBrains provides a helpful lay overview of this study in A Love affair Across Generations: A Lamarckian Reincarnation? He takes up the environmental enrichment angle, notes the contributions of pioneering researchers (i.e., Dr. Marian C. Diamond and Dr. William T. Greenough), and concludes with the importance of this work for educators.

These results provide our second example of neuroplasticity resulting from environmental enrichment (e.g., “exposure to novel objects, elevated social interactions and voluntary exercise”) in rodents. What about neuroplasticity in humans? What constitutes effective "environmental enrichment"? The "brain training" industry is big business now. Rats aren't susceptible to overbearing marketing tactics or the placebo effect, so how do you separate the help from the hype? Two recent papers are of interest here. The first did a meta-analysis of studies examining the effects of brain training programs in healthy elderly participants (Papp et al., 2009). The authors concluded that the cognitive interventions weren't very effective. The second paper [the IMPACT study] reported modest benefits in auditory memory/attention from engaging in a particular computerized training program (Smith et al., 2009). In Brain Training: It Works, and It Doesn't Work, Alvaro Fernandez discusses the IMPACT study and suggests we move beyond simplistic notions that such training programs are either magic bullets or completely bogus. Look for commentary from The Neurocritic in the coming days...

Are you superstitious? Were you afraid to use your laptop on Friday the 13th? Or were you feeling lucky?



Dr. Romeo Vitelli of Providentia is not a gambling man. In Playing The Odds, a recent trip to Las Vegas reminded him of B.F. Skinner, operant conditioning, and his days as an undergraduate psychology major. Similarities between the variable reinforcement schedule provided to a white lab rat in a Skinner Box and a human gambler playing those slot machines were noted.

Still feeling irrational? Then watch Dan Ariely: Tendencies of Irrational Behavior, via Channel N. Behavioral economist Ariely gives a witty 20 minute lecture explaining cognitive illusions, defaults, and irrational decision-making. A nice FORA.tv presentation with enhanced multimedia features.

In Temperamental Journey, Doc (aka Mormon MD) of Mind, Soul, and Body reviews Jerome Kagan’s seminal work on temperament in infants and links to an archival interview with Natasha Mitchell for an All in the Mind Podcast. The inevitable nature/nurture question arises during the course of the interview. Is who we are determined more by experience or biology? “Why does this question persist?” is my own reply to the query. I think it is a false dichotomy, as do most reasonable contemporary scientists. As Kagan explains:
‘the development of a person is like a cloth that appears to us to be grey but it’s composed of infinitely tiny black threads - biology - infinitely tiny white threads - experience - but you don’t see any black and white threads, all you see is the grey cloth.’ A person is that cloth and it’s combined of both and to ask which is more important is like asking about a Christmas blizzard - which is more important the temperature or the humidity? The answer is they are both important.”
Doc uses this viewpoint as a segue to his discuss own experience as a pediatric neurologist. Although I am much more of a reductionist, he does provide an interesting perspective on the acceptance of ambiguity in clinical practice.

Joseph Kim of Brain Blogger offers an opinion piece on Bias in Medical Education. "Is all bias bad?" he asks. Or are some forms of bias appropriate? For example, take this Primer on Acupuncture. There are plenty of reasons to be biased against alternative medical treatments that don't work. Here are a few of the reasons why Steve Novella Is Skeptical of Acupuncture:
1) Acupuncture is a pre-scientific superstition

2) Acupuncture lacks a plausible mechanism

3) Claims for efficacy are often based upon a bait-and-switch deception

4) Clinical trials show that acupuncture does not work
But I guess that's pretty "biased" of him, isn't it?

Advances in the History of Psychology returns to our carnival after a long absence. Jeremy Burman has submitted a quartet of posts to prevent Encephalon readers from slipping into an ahistoric stupor. Let's begin with a video on the origins of Experimental Psychology, which features Chris Green (president of the Society for the History of Psychology) in “an impossibly brief history of the origins of experimental psychology, from Aristotle to Wundt.”

An exciting new resource is now available online! Scientifica: Source of French Phrenology provides links to the phrenology collection. After that, you can witness The Demise of Dutch Phenomenological Psych.


And for the Anglophiles who assumed that dusty old 19th century psychoanalysis was only for literary critics: think again! Fiction and 'la guerre des psys' in France informs us that only recently have the French taken up the fad of psychoanalysis-bashing and CBT-promotion (Kemp, 2008), sparking what
L’Express has dubbed ‘la guerre des psys’… The French media widely discussed a controversial 2004 report by INSERM, Psychothérapie, trois approches évalués, which found psychoanalysis ineffective in the treatment of schizophrenia and depression, and vaunted the benefits of cognitive behaviour therapy.

Really? You mean schizophrenia can’t be cured by 1,000 sessions on the couch in an analyst's office?

Another historical post is provided by Providentia. In Shooting Dr. Tourette, we learn that the prominent French neurologist (the eponym of Tourette's syndrome) was shot in the back of the neck by a former patient:

Rose maintained that Tourette and the other Salpetriere doctors had hypnotized her against her will and her defense attorney even argued that the hypnosis had somehow caused the shooting. Following a sensational trial, the judge eventually ruled that hypnosis had nothing to do with Rose Kamper's actions and she was declared insane.

Although Dr. Tourette recovered physically from the shooting, the emotional impact would linger. Rose Kamper's testimony and the heavy newspaper coverage of the trial damaged his professional reputation. Despite his fame as a physician and numerous honours, Gilles de la Tourette's condition began deteriorating with fluctuating episodes of depression, mania and mental confusion.

He died at the age of 46, possibly from neurosyphilis.

Our next post is positively prehistoric. The second entry from Neurophilosophy presents a fascinating review on the Brain & behaviour of dinosaurs. It summarizes the work of Lawrence Witmer and colleagues, who scan fossilized dinosaur skulls and then use sophisticated micro-computed tomographic techniques to reconstruct their brains. Then they make inferences about the dinosaurs' behavior.

Now it's back to the present with a three-part series from JLK of Pieces of Me on the psychology of men and the construction of masculinity.

Gender Part 1: Boys Don't Cry

Gender Part 1: Better Than Thou


Gender Part 1: Defining Manhood



Brandon Teena (a.k.a. Teena Brandon)
Born: December 12, 1972
Birthplace: Lincoln, Nebraska,
Date of Death: December 31, 1993 (murdered)

It's intended to be part of an even larger series on gender:
My intention is to compose a series of posts dedicated to this topic. I will cover women's, men's, transgender, and intersex issues over the course of the series. They will be primarily non-academic in nature because I know that most of my readers are in vastly different fields. Therefore, I will refer you to books and things that are written for the masses for more information, and if anyone wants journal articles just let me know. Favorite books on the topic are interspersed throughout the post.
Why aren't there any men's studies programs? Isn't that a silly idea?
What we have created is a male culture that values fierce independence, control or lack of emotions, no tolerance for weakness, and a disdain for anything "feminine."

Men aren't born that way. We make them that way. And then we wonder why women have a hard time getting ahead in a male-dominated career path, why the kiss of death for a woman is to cry at work, why men don't help out with children and the household as much as we would like them to, why HOMOPHOBIA EXISTS.
There's so much ugliness in the world, so let's turn to something beautiful, and that would be Brainbow.


A Snapshot of Memory. This image from the hippocampus shows smaller glial cells (the small ovals) among neurons (larger, with more filaments). The hippocampus is known to play a major role in memory formation.

For more on this artful science, read Fantastic Fluorescence: Brainbow and The Nobel Prize 2008.

Last (but not least) is a fun demonstration from Cognitive Daily that uses the rapid serial visual presentation (RSVP) method. What are The words you can't ignore, even if you only see them for 1/10 of a second? Sex words and taboo words draw attention away from the task of detecting a target word (color names) in the visual stream. See for yourself!



That's it for this edition. Thanks to everyone who contributed. The next Encephalon will appear on March 2 at PodBlack Cat.

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11 Comments:

At February 18, 2009 8:13 PM, Blogger Ward said...

Wow, that was a lot of work and you did a very impressive job of tying the various submissions together. Great work.

 
At February 18, 2009 8:35 PM, Blogger The Neurocritic said...

Thanks, Ward.

 
At February 18, 2009 8:55 PM, Anonymous Anonymous said...

Wow! That's quite a collection. Thanks for including us (AHP). But, more than that, thanks for putting in what was obviously a major effort.

 
At February 18, 2009 9:24 PM, Blogger Ward said...

This comment has been removed by the author.

 
At February 18, 2009 9:50 PM, Blogger Andy McKenzie said...

This is pretty impressive man, good work.

 
At February 18, 2009 9:59 PM, Blogger Ward said...

I would like to thank you (neurocritic) for pointing out my stupid mistakes (I guess that what happens when you try to write outside of your field - and get lost in the race to tell a story). I have gone back and tried to find more references to cover antidepressants and point out where the theory falls short. I also credit you for pointing out my mistakes.

thanks again.

I will try to keep updating my piece it in an attempt at getting the information correct.

 
At February 18, 2009 10:49 PM, Blogger Doctor Spurt said...

Three cheers - this is a terrific edition of the carnival!

 
At February 18, 2009 10:53 PM, Anonymous Anonymous said...

Glad to hear of your interest in the IMPACT study - I look forward to your post. If you want a preprint of the paper, or have any questions, please email me at henry.mahncke at positscience.com

I posted on the study at a Posit Science blog.

 
At February 19, 2009 4:22 PM, Blogger The Neurocritic said...

Thanks, everyone.

Henry - I do have a copy of the paper already.

 
At February 27, 2009 9:05 AM, Anonymous Anonymous said...

Hey, where did you get your information on the old lie detector tests in China and West Africa? I cannot seem to find an original source. - Thanks!

 
At March 08, 2009 8:39 PM, Blogger The Science Police said...

Hi again.

We share your interest (and skepticism) for research on autism. Please find a new post (and a poll), we'd be interested to hear your take on...

http://thesciencepolice.blogspot.com/
The Science Police

 

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