How psychedelics affect our brain - unconstrained cognition

Carhart-Harris et al. have done an interesting study showing that psilocybin decreases surrogate markers for neuronal activity [cerebral blood flow and blood oxygen level-dependent (BOLD) signals] in key brain regions implicated in psychedelic drug actions. They also report that psilocybin appears to decrease brain “connectivity” as measured by pharmaco-physiological interaction. Their results imply that "the subjective effects of psychedelic drugs are caused by decreased activity and connectivity in the brain's key connector hubs, enabling a state of unconstrained cognition."

Psychedelic drugs have a long history of use in healing ceremonies, but despite renewed interest in their therapeutic potential, we continue to know very little about how they work in the brain. Here we used psilocybin, a classic psychedelic found in magic mushrooms, and a task-free functional MRI (fMRI) protocol designed to capture the transition from normal waking consciousness to the psychedelic state. Arterial spin labeling perfusion and blood-oxygen level-dependent (BOLD) fMRI were used to map cerebral blood flow and changes in venous oxygenation before and after intravenous infusions of placebo and psilocybin. Fifteen healthy volunteers were scanned with arterial spin labeling and a separate 15 with BOLD. As predicted, profound changes in consciousness were observed after psilocybin, but surprisingly, only decreases in cerebral blood flow and BOLD signal were seen, and these were maximal in hub regions, such as the thalamus and anterior and posterior cingulate cortex (ACC and PCC). Decreased activity in the ACC/medial prefrontal cortex (mPFC) was a consistent finding and the magnitude of this decrease predicted the intensity of the subjective effects. Based on these results, a seed-based pharmaco-physiological interaction/functional connectivity analysis was performed using a medial prefrontal seed. Psilocybin caused a significant decrease in the positive coupling between the mPFC and PCC. These results strongly imply that the subjective effects of psychedelic drugs are caused by decreased activity and connectivity in the brain's key connector hubs, enabling a state of unconstrained cognition.

Brain deactivations after psilocybin. (Upper) Regions where there was a significant decrease in the BOLD signal after psilocybin versus after placebo. (Lower) Regions where there was a consistent decrease in CBF (cerebral blood flow) and BOLD after psilocybin. We observed no increases in CBF or BOLD signal in any region.

Life is a digital code.

Here is a nicely done precis of a crucial bit of our intellectual history from science written by Matt Ridley, his answer to "What is your favorite deep, elegant or beautiful explanation.":

It's hard now to recall just how mysterious life was on the morning of 28 February and just how much that had changed by lunchtime. Look back at all the answers to the question "what is life?" from before that and you get a taste of just how we, as a species, floundered. Life consisted of three-dimensional objects of specificity and complexity (mainly proteins). And it copied itself with accuracy. How? How do you set about making a copy of a three-dimensional object? How to do you grow it and develop it in a predictable way? This is the one scientific question where absolutely nobody came close to guessing the answer. Erwin Schrodinger had a stab, but fell back on quantum mechanics, which was irrelevant. True, he used the phrase "aperiodic crystal" and if you are generous you can see that as a prediction of a linear code, but I think that's stretching generosity.

Indeed, the problem had just got even more baffling thanks to the realization that DNA played a crucial role—and DNA was monotonously simple. All the explanations of life before 28 Feb 1953 are hand-waving waffle and might as well speak of protoplasm and vital sparks for all the insights they gave.

Then came the double helix and the immediate understanding that, as Crick wrote to his son a few weeks later, "some sort of code"—digital, linear two-dimensional, combinatorially infinite and instantly self-replicating—was all the explanation you needed. Here's part of Francis Crick's letter, 17 March 1953:

"My Dear Michael,

Jim Watson and I have probably made a most important discovery...Now we believe that the DNA is a code. That is, the order of the bases (the letters) makes one gene different from another gene (just as one page pf print is different from another). You can see how Nature makes copies of the genes. Because if the two chains unwind into two separate chains, and if each chain makes another chain come together on it, then because A always goes with T, and G with C, we shall get two copies where we had one before. In other words, we think we have found the basic copying mechanismby which life comes from life...You can understand we are excited."

Never has a mystery seemed more baffling in the morning and an explanation more obvious in the afternoon.

Testosterone, digit ratio, and abstract reasoning ability

Brañas-Garza and Aldo Rustichini suggest that perhaps higher testosterone market traders are more successful not only because they are greater risk takers, but also because their abstract reasoning abilities are superior:

Recent literature emphasizes the role that testosterone, as well as markers indicating early exposure to T and its organizing effect on the brain (such as the ratio of second to fourth finger, ), have on performance in financial markets. These results may suggest that the main effect of T, either circulating or in fetal exposure, on economic behavior occurs through the increased willingness to take risks. However, these findings indicate that traders with a low digit ratio are not only more profitable, but more able to survive in the long run, thus the effect might consist of more than just lower risk aversion. In addition, recent literature suggests a positive correlation between abstract reasoning ability and higher willingness to take risks. To test the two hypotheses of testosterone on performance in financial activities (effect on risk attitude versus a complex effect involving risk attitude and reasoning ability), we gather data on the three variables in a sample of 188 ethnically homogeneous college students (Caucasians). We measure a digit ratio, abstract reasoning ability with the Raven Progressive Matrices task, and risk attitude with choice among lotteries. Low digit ratio in men is associated with higher risk taking and higher scores in abstract reasoning ability when a combined measure of risk aversion over different tasks is used. This explains both the higher performance and higher survival rate observed in traders, as well as the observed correlation between abstract reasoning ability and risk taking. We also analyze how much of the total effect of digit ratio on risk attitude is direct, and how much is mediated. Mediation analysis shows that a substantial part of the effect of T on attitude to risk is mediated by abstract reasoning ability.

Us vs. them in context.

As I scan the tables of contexts of journals for items that might be appropriate for MindBlog, I am majorly influenced by a catchy title and relative brevity, the old brain doesn’t have to work as hard. (In this vein, see the recent essay on "Bite Size" Science.) Gilbert Chin of Science Magazine notes that a plain title I passed over points to an interesting piece of work, showing that our attitude towards pluralism and tolerance can depend very much on whether we are in the majority or minority of the relevant social group. From Chin's summary:

Us versus Them is both an enduring view of the world and a malleable one. It is enduring in the sense that groups form naturally even where there are no preexisting differences and malleable in the sense that the group that one identifies with can change over time or between situations. Theoretical and empirical evidence justifies the generalization that members of a majority group tend to favor the assimilation of immigrants into the native culture, whereas immigrants are more likely to vote for pluralistic policies that acknowledge the distinctiveness of minority cultures.

The abstract of the article:

This research examined preferences for national- and campus-level assimilative and pluralistic policies among Black and White students under different contexts, as majority- and minority-group members. We targeted attitudes at two universities, one where 85% of the student body is White, and another where 76% of students are Black. The results revealed that when a group constituted the majority, its members generally preferred assimilationist policies, and when a group constituted the minority, its members generally preferred pluralistic policies. The results support a functional perspective: Both majority and minority groups seek to protect and enhance their collective identities.

Even if the juice is a placebo...

I thought the stuff on the oxytocin spray in the previous post was a hoot, and so dashed off the post on receiving a colleague's email on it yesterday.  Several alert readers have immediately sent in appropriately skeptical comments.  Cursory inspection of the website shows the product to be from a homeopathic outfit, the product description actually gives NO CLUE on how much oxytocin (plus a lot of other claimed stuff) is present.  But hey.... I guess $50 for the product should reinforce a pretty good placebo effect!

Juice up your Valentine's day!

I've done numerous posts on oxytocin effects on us humans (enter oxytocin in the search box in the left column). Generally, it makes us nicer and more affiliative. A recent email from a colleague who diligently sends me results of his wide ranging web scans for enhancers of vitality, longevity, etc. makes me aware that getting a nip of oxytocin for yourself is like falling off a log (if you are also willing to part with ~50-60 dollars for nasal or sublingual versions). He has tried the sub-lingual spray and says it does work "although the subjective results are highly-dependent upon my physiological/mental state and/or the time of day. There are also quite likely different genetic predispositions as reported in Deric's mind blog." I would be curious to try the stuff, but don't want to threaten the curmudgeonly behavior that I normally enjoy.

Don't go to bed angry...

Several studies have shown that sleep enhances emotional memories. Baran et al. show that maybe its better let anger keep you awake at night than to sleep on it. Sleep consolidates the negative emotional memory. Having trouble sleeping after an unsettling experience may be the brain's way of trying to keep the memory or emotion from being stored. The abstract:

Sleep enhances memories, particularly emotional memories. As such, it has been suggested that sleep deprivation may reduce posttraumatic stress disorder. This presumes that emotional memory consolidation is paralleled by a reduction in emotional reactivity, an association that has not yet been examined. In the present experiment, we used an incidental memory task in humans and obtained valence and arousal ratings during two sessions separated either by 12 h of daytime wake or 12 h including overnight sleep. Recognition accuracy was greater following sleep relative to wake for both negative and neutral pictures. While emotional reactivity to negative pictures was greatly reduced over wake, the negative emotional response was relatively preserved over sleep. Moreover, protection of emotional reactivity was associated with greater time in REM sleep. Recognition accuracy, however, was not associated with REM. Thus, we provide the first evidence that sleep enhances emotional memory while preserving emotional reactivity.

Our connectomes 'R Us?

I have received by now several offers from Houghton Mifflin publishers to send a reviewer's copy of Sebastian Seung's "Connectome: How the Brain's Wiring Makes Us Who We Are." I haven't acted on it, because a review of the synopsis has convinced me that Seung's own brilliant efforts, and similar works he describes to map every connection in our brain, are not the complete key to understanding ourselves that he implies. I was actually starting to write a list of problems I see with the idea that when you've got the wiring diagram between nerve cells you've got it all, but this succinct critique by Chris Koch permits me to be lazy:

Treating the connectome as the be-all and end-all of brain function has its problems. Seung, for example, rebrands autism and schizophrenia as 'connectopathies' — diseases in which the brain's wiring goes awry. Yet plenty of other things are wrong in brains with these disorders besides their connectivity.

Faults in synaptic transmission and in processes inside neurons and the glial cells that support them have all been implicated in mental illness and brain disease. Neurons are intricate devices with elaborate input structures that show complex, time-dependent and nonlinear processing. They have various characteristic, and often tortuous, morphologies. Connectionism treats all this as irrelevant. Even though we have known the connectome of the nematode worm for 25 years, we are far from reading its mind. We don't yet understand how its nerve cells work.

Massage therapy suppresses expression of inflammatory genes after exercise..

I've been getting regular deep tissue structural massage for years, and continue to be amazed at how good it makes me feel. This report from Tarnopolsky and colleagues explains at least part of the reason why. They profiled the expression of genes involved in both inflammatory pathways and in pathways that regenerate energy generating mitochondria in the leg muscles of eleven young men after very strenuous leg exercise, with one leg being massaged after the exercise. The massaged legs had 30% more PGC-1alpha, a gene that helps muscle cells build mitochondria. They also had three times less NFkB, which turns on genes associated with inflammation. (The study found no evidence to support often-repeated claims that massage removes lactic acid, a byproduct of exertion long blamed for muscle soreness, or waste products from tired muscles.) Here is the detailed abstract:

Massage therapy is commonly used during physical rehabilitation of skeletal muscle to ameliorate pain and promote recovery from injury. Although there is evidence that massage may relieve pain in injured muscle, how massage affects cellular function remains unknown. To assess the effects of massage, we administered either massage therapy or no treatment to separate quadriceps of 11 young male participants after exercise-induced muscle damage. Muscle biopsies were acquired from the quadriceps (vastus lateralis) at baseline, immediately after 10 min of massage treatment, and after a 2.5-hour period of recovery. We found that massage activated the mechanotransduction signaling pathways focal adhesion kinase (FAK) and extracellular signal–regulated kinase 1/2 (ERK1/2), potentiated mitochondrial biogenesis signaling [nuclear peroxisome proliferator–activated receptor γ coactivator 1α (PGC-1α)], and mitigated the rise in nuclear factor κB (NFκB) (p65) nuclear accumulation caused by exercise-induced muscle trauma. Moreover, despite having no effect on muscle metabolites (glycogen, lactate), massage attenuated the production of the inflammatory cytokines tumor necrosis factor–α (TNF-α) and interleukin-6 (IL-6) and reduced heat shock protein 27 (HSP27) phosphorylation, thereby mitigating cellular stress resulting from myofiber injury. In summary, when administered to skeletal muscle that has been acutely damaged through exercise, massage therapy appears to be clinically beneficial by reducing inflammation and promoting mitochondrial biogenesis.

The good life can be a killer.

I've enjoyed the recent piece on our dysfunctional modern community structures by Jane Brodie (who got her journalism degree at the University of Wisconsin, Madison, where I teach).

...homes and shopping malls far from city centers…[have created] creating vehicle-dependent environments that foster obesity, poor health, social isolation, excessive stress and depression…Physical activity has been disappearing from the lives of young and old, and many communities are virtual “food deserts,” serviced only by convenience stores that stock nutrient-poor prepared foods and drinks…people in the current generation (born since 1980) will be the first in America to live shorter lives than their parents do.

In a healthy environment…people who are young, elderly, sick or poor can meet their life needs without getting in a car, which means creating places where it is safe and enjoyable to walk, bike, take in nature and socialize…People who walk more weigh less and live longer…People who are fit live longer… People who have friends and remain socially active live longer…In 1974, 66 percent of all children walked or biked to school By 2000, that number had dropped to 13 percent…We’ve engineered physical activity out of children’s lives…two in seven volunteers for the military can’t get in because they’re not in good enough physical condition…Not only are Americans of all ages fatter than ever, but also growing numbers of children are developing diseases once seen only in adults: Type 2 diabetes, heart disease and fatty livers.

On the question of whether our suburbs can be saved, Brodie notes environmental redesigning projects to foster better physical and mental health proceeding in Atlanta, GA., Lakewood, CO., Syracuse, NY, and Elgin, IL. (and, see designinghealthycommunities.org.)

Should I use condoms for sex? The millisecond scan.

This item caught my eye, since I spend the winter months each year living in the center of the gay Wilton Manors ghetto of Fort Lauderdale, FL., where the boys hook up at a fast and furious rate. Many base a decision on whether to use condoms on their 'intuition' of whether a potential partner is HIV positive. Renner et al. find that this guessing is very rapid and based on a few fairly simple facial trait characteristics (that in fact have not been shown to have any relationship to actual HIV status).

Research indicates that many people do not use condoms consistently but instead rely on intuition to identify sexual partners high at risk for HIV infection. The present studies examined neural correlates for first impressions of HIV risk and determined the association of perceived HIV risk with other trait characteristics. Participants were presented with 120 self-portraits retrieved from a popular online photo-sharing community (www.flickr.com). Factor analysis of various explicit ratings of trait characteristics yielded two orthogonal factors: (1) a ‘valence-approach’ factor encompassing perceived attractiveness, healthiness, valence, and approach tendencies, and (2) a ‘safeness’ factor, entailing judgments of HIV risk, trustworthiness, and responsibility. These findings suggest that HIV risk ratings systematically relate to cardinal features of a high-risk HIV stereotype. Furthermore, event-related brain potential recordings revealed neural correlates of first impressions about HIV risk. Target persons perceived as risky elicited a differential brain response in a time window from 220–340 ms and an increased late positive potential in a time window from 350–700 ms compared to those perceived as safe. These data suggest that impressions about HIV risk can be formed in a split second and despite a lack of information about the actual risk profile. Findings of neural correlates of risk impressions and their relationship to key features of the HIV risk stereotype are discussed in the context of the ‘risk as feelings’ theory.

Simplicity itself.

I have to pass on this brief essay by one of my heroes, Thomas Metzinger:

Elegance is more than an aesthetic quality, or some ephemeral sort of uplifting feeling we experience in deeper forms of intuitive understanding. Elegance is formal beauty. And formal beauty as a philosophical principle is one of the most dangerous, subversive ideas humanity has discovered: it is the virtue of theoretical simplicity. Its destructive force is greater than Darwin's algorithm or that of any other single scientific explanation, because it shows us what the depth of an explanation is.

Elegance as theoretical simplicity comes in many different forms. Everybody knows Occam's razor, the ontological principle of parsimony: Entities are not to be multiplied beyond necessity. William of Occam gave us a metaphysical principle for choosing between competing theories: All other things being equal, it is rational to always prefer the theory that makes fewer ontological assumptions about the kinds of entities that really exist (souls, life forces, abstract objects, or an absolute frame of reference like electromagnetic ether). We are to admit no more causes of natural things than such as are both true and sufficient to explain their appearances—Isaac Newton formulated this as the First Rule of Reasoning in Philosophy, in his Principia Mathematica. Throw out everything that is explanatorily idle, and then shift the burden of proof to the proponent of a less simple theory. In Albert Einstein's words: The grand aim of all science … is to cover the greatest possible number of empirical facts by logical deductions from the smallest possible number of hypotheses or axioms.

Of course, in today's technical debates new questions have emerged: Why do metaphysics at all? Isn't it simply the number of free, adjustable parameters in competing hypotheses what we should measure? Is it not syntactic simplicity that captures elegance best, say, the number fundamental abstractions and guiding principles a theory makes use of? Or will the true criterion for elegance ultimately be found in statistics, in selecting the best model for a set of data points while optimally balancing parsimony with the "goodness of fit" of a suitable curve? And, of course, for Occam-style ontological simplicity the BIG question always remains: Why should a parsimonious theory more likely be true? Ultimately, isn't all of this rooted in a deeply hidden belief that God must have created a beautiful universe?

I find it fascinating to see how the original insight has kept its force over the centuries. The very idea of simplicity itself, applied as a metatheoretical principle, has demonstrated great power—the subversive power of reason and reductive explanation. The formal beauty of theoretical simplicity is deadly and creative at the same time. It destroys superfluous assumptions whose falsity we just cannot bring ourselves to believe, whereas truly elegant explanations always give birth to an entirely new way of looking at the world. What I would really like to know is this: Can the fundamental insight—the destructive, creative virtue of simplicity—be transposed from the realm of scientific explanation into culture or onto the level of conscious experience? What kind of formal simplicity would make our culture a deeper, more beautiful culture? And what is an elegant mind?

Our Thrifty Brains.

Andy Clark has done a piece that is really worth reading in the Stone, a New York Times forum for contemporary philosophers. (And, check out the video below):

Might the miserly use of neural resources be one of the essential keys to understanding how brains make sense of the world? Some recent work in computational and cognitive neuroscience suggests that it is indeed the frugal use of our native neural capacity (the inventive use of restricted “neural bandwidth,” if you will) that explains how brains like ours so elegantly make sense of noisy and ambiguous sensory input. That same story suggests, intriguingly, that perception, understanding and imagination, which we might intuitively consider to be three distinct chunks of our mental machinery, are inextricably tied together as simultaneous results of a single underlying strategy known as “predictive coding.” This strategy saves on bandwidth using (who would have guessed it?) one of the many technical wheezes that enable us to economically store and transmit pictures, sounds and videos using formats such as JPEG and MP3.

...perception may best be seen as what has sometimes been described as a process of “controlled hallucination” ...in which we (or rather, various parts of our brains) try to predict what is out there, using the incoming signal more as a means of tuning and nuancing the predictions rather than as a rich (and bandwidth-costly) encoding of the state of the world.

The basic effect hereabouts is neatly illustrated by a simple but striking demonstration (used by the neuroscientist Richard Gregory back in the 1970’s to make this very point) known as “the hollow face illusion.” This is a well-known illusion in which an ordinary face mask viewed from the back can appear strikingly convex. That is, it looks (from the back) to be shaped like a real face, with the nose sticking outward rather than having a concave nose cavity. Just about any hollow face mask will produce some version of this powerful illusion, and there are many examples on the Web, like this one:

A simple way to attentuate emotional arousal?

I just came across these interesting observations of Herwig et al.. They show that simply using self referential reflection (i.e., using mindfullness) to make an emotional state aware can attenuate amygdala activation and emotional arousal:

The regulation of emotions is an ongoing internal process and often a challenge. Current related neural models concern the intended control of reactions towards external events, mediated by prefrontal cortex regions upon basal emotion processing as in the amygdala. Cognitive strategies to regulate emotions in the context of affective disorders or stress reduction, increasingly applied in clinical practice, are also related to mindfulness techniques. We questioned their effects on neural emotion processing and investigated brain activity during purely internal mental self-referential processes of making current emotions and self-related cognitions aware. Thirty healthy subjects performed a task comprising periods of cognitive self-reflection, of introspection for actual own emotions and feelings, and of a neutral condition, while they were scanned with functional magnetic resonance imaging. Brain activations of twenty-seven subjects during emotion-introspection and self-reflection, and also a conjunction of both, were compared with the neutral condition. The conditions of self-reflection and emotion-introspection showed distinguishable activations in medial and ventrolateral prefrontal areas, in parietal regions and in the amygdala. Notably, amygdala activity decreased during emotion-introspection and increased compared to ‘neutral’ during self-reflection. The results indicate that already the self-referential mental state of making the actual emotional state aware is capable of attenuating emotional arousal. This extends current theories of emotion regulation and has implications for the application of mindfulness techniques as a component of psychotherapeutic strategies in affective disorders and also for possible everyday emotion regulation.

You think, therefore I am.

I pass on this contribution from Rose and Markus as their answer to this year's annual question from Edge.org (What is your favorite deep, elegant, or beautiful explanation?):

"I think, therefore I am." Cogito ergo sum. Remember this elegant and deep idea from René Descartes' Principles of Philosophy? The fact that a person is contemplating whether she exists, Descartes argued, is proof that she, indeed, actually does exist. With this single statement, Descartes knit together two central ideas of Western philosophy: 1) thinking is powerful, and 2) individuals play a big role in creating their own I's—that is, their psyches, minds, souls, or selves.

Most of us learn "the cogito" at some point during our formal education. Yet far fewer of us study an equally deep and elegant idea from social psychology: Other people's thinking likewise powerfully shapes the I's that we are. Indeed, in many situations, other people's thinking has a bigger impact on our own thoughts, feelings, and actions than do the thoughts we conjure while philosophizing alone.

In other words, much of the time, "You think, therefore I am." For better and for worse.

An everyday instance of how your thinking affects other people's being is the Pygmalion effect. Psychologists Robert Rosenthal and Lenore Jacobson captured this effect in a classic 1963 study. After giving an IQ test to elementary school students, the researchers told the teachers which students would be "academic spurters" because of their allegedly high IQs. In reality, these students' IQs were no higher than those of the "normal" students. At the end of the school year, the researchers found that the "spurters'" had attained better grades and higher IQs than the "normals." The reason? Teachers had expected more from the spurters, and thus given them more time, attention, and care. And the conclusion? Expect more from students, and get better results.

A less sanguine example of how much our thoughts affect other people's I's is stereotype threat. Stereotypes are clouds of attitudes, beliefs, and expectations that follow around a group of people. A stereotype in the air over African Americans is that they are bad at school. Women labor under the stereotype that they suck at math.

As social psychologist Claude Steele and others have demonstrated in hundreds of studies, when researchers conjure these stereotypes—even subtly, by, say, asking people to write down their race or gender before taking a test—students from the stereotyped groups score lower than the stereotype-free group. But when researchers do not mention other people's negative views, the stereotyped groups meet or even exceed their competition. The researchers show that students under stereotype threat are so anxious about confirming the stereotype that they choke on the test. With repeated failures, they seek their fortunes in other domains. In this tragic way, other people's thoughts deform the I's of promising students.

As the planet gets smaller and hotter, knowing that "You think, therefore I am" could help us more readily understand how we affect our neighbours and how our neighbours affect us. Not acknowledging how much we impact each other, in contrast, could lead us to repeat the same mistakes.

Cellular 'self eating' accounts for some beneficial effects of exercise.

Population studies suggest that exercise protects against diabetes, cancer, and age related diseases such as Alzheimer's. Work by Congcong He et al. has now shown that at least part of this effect is due to the increased "self-eating" (Autophagy) that cells must do to meet the energy demands of exercise. Autophagy recycles used or flawed membranes and internal cell structures by encircling its target material and then dumping it into a compartment that digests it. It has been shown in animal models to reduce diabetes, cancer, and neuro-degenerative diseases. The He et al. work documents that exercise induces autophagy in the skeletal muscles of mice, which in turn lowers glucose and insulin in the bloodstream. Mutant mice that don't induce more autophagy during exercise didn't show this effect. Further, the exercise induced reversal of diabetes induced by overfeeding mice was observed only the mice who showed a exercise induced increased autophagy. Here is the abstract with more details:

Exercise has beneficial effects on human health, including protection against metabolic disorders such as diabetes. However, the cellular mechanisms underlying these effects are incompletely understood. The lysosomal degradation pathway, autophagy, is an intracellular recycling system that functions during basal conditions in organelle and protein quality control. During stress, increased levels of autophagy permit cells to adapt to changing nutritional and energy demands through protein catabolism. Moreover, in animal models, autophagy protects against diseases such as cancer, neurodegenerative disorders, infections, inflammatory diseases, ageing and insulin resistance. Here we show that acute exercise induces autophagy in skeletal and cardiac muscle of fed mice. To investigate the role of exercise-mediated autophagy in vivo, we generated mutant mice that show normal levels of basal autophagy but are deficient in stimulus (exercise- or starvation)-induced autophagy. These mice (termed BCL2 AAA mice) contain knock-in mutations in BCL2 phosphorylation sites (Thr69Ala, Ser70Ala and Ser84Ala) that prevent stimulus-induced disruption of the BCL2–beclin-1 complex and autophagy activation. BCL2 AAA mice show decreased endurance and altered glucose metabolism during acute exercise, as well as impaired chronic exercise-mediated protection against high-fat-diet-induced glucose intolerance. Thus, exercise induces autophagy, BCL2 is a crucial regulator of exercise- (and starvation)-induced autophagy in vivo, and autophagy induction may contribute to the beneficial metabolic effects of exercise.

The psychology of perceived wealth.

Studies have shown that not every dollar contributes equally to perceived wealth, people’s standing relative to those around them often predicts well-being better than net worth does, and increasing income trends are preferred over decreasing ones. Sussman and Shafir (at Princeton, where Kahneman has carried out his behavioral economics studies) show several factors that can influence the perception of wealth:

We studied the perception of wealth as a function of varying levels of assets and debt. We found that with total wealth held constant, people with positive net worth feel and are seen as wealthier when they have lower debt (despite having fewer assets). In contrast, people with equal but negative net worth feel and are considered wealthier when they have greater assets (despite having larger debt). This pattern persists in the perception of both the self and others.

In their concluding discussion,

…people have a robust preference for higher assets in cases of negative net worth and for lower debt in cases of positive net worth…debt appears relatively salient in contexts of positive wealth, whereas assets loom relatively large in contexts of negative wealth, and this differential salience has a corresponding impact on financial judgments and decisions.

…the present findings show how the appeal of a loan may depend on one’s perceived financial state. For a person who is in the red, a loan may provide an appealing infusion of cash, whereas for a person in the black, it might present an aversive incursion into debt. Conversely, people who are in the black may be tempted to diminish their debt, whereas it may prove unappealing for those in the red to lower their debt at the expense of their assets.

Remarkably, the same striving for financial wealth and stability can trigger opposing behaviors: preference for greater assets in some circumstances, and for lower debt in others. Such impulses may not always be aligned with what is best financially. People who are in the red and eager to borrow will sometimes have access only to high-interest loans. And people who are eager to clear their debt will sometimes do so even when their debt (e.g., tax-incentivized mortgages) is financially beneficial. Such psychology may be of great consequence. A remarkable 25% of U.S. households had zero or negative net worth in 2009 (for Black households, the figure was about 40%. Better insight into the determinants of perceived financial wealth and financial decision making could help shape behaviorally informed policy.

Bounded rationality.

I thought I would pass on clips from Mahzarin Banaji's response to the Edge.org annual question "What is your favorite deep, elegant, or beautiful explanation?":

…my candidate for the most deeply satisfying explanation of recent decades is the idea of bounded rationality…Herbert Simon put one stake in the ground through the study of information processing and AI, showing that both people and organizations follow principles of behavior such as "satisficing" that constrain them to decent but not the best decisions. The second stake was placed by Kahneman and Tversky, who showed the stunning ways in even experts are error-prone—with consequences for not only their own health and happiness but that of their societies broadly.

Together the view of human nature that evolved over the past four decades has systematically changed the explanation for who we are and why we do what we do. We are error-prone in the unique ways in which we are, the explanation goes, not because we have malign intent, but because of the evolutionary basis of our mental architecture, the manner in which we remember and learn information, the way in which we are affected by those around us and so on. The reason we are boundedly rational is because the information space in which we must do our work is large compared to the capacities we have, including severe limits on conscious awareness, the ability to be able to control behavior, and to act in line even with our own intentions.

The idea that bad outcomes result from limited minds that cannot store, compute and adapt to the demands of the environment is a radically different explanation of our capacities and thereby our nature. It's elegance and beauty comes from it placing the emphasis on the ordinary and the invisible rather than on specialness and malign motives. This seems not so dissimilar from another shift in explanation from god to natural section and it is likely to be equally resisted. 

The age of anxiety

Daniel Smith does an interesting piece asking whether it is appropriate to consider our current times an "age of anxiety." Some clips:

...it is undeniable that ours is an age in which an enormous and growing number of people suffer from anxiety. According to the National Institute of Mental Health, anxiety disorders now affect 18 percent of the adult population of the United States, or about 40 million people. By comparison, mood disorders — depression and bipolar illness, primarily — affect 9.5 percent…anti-anxiety drug alprazolam — better known by its brand name, Xanax — was the top psychiatric drug on the list, clocking in at 46.3 million prescriptions in 2010.

Just because our anxiety is heavily diagnosed and medicated, however, doesn’t mean that we are more anxious than our forebears. It might simply mean that we are better treated — that we are, as individuals and a culture, more cognizant of the mind’s tendency to spin out of control.

Earlier eras might have been even more jittery than ours. Fourteenth-century Europe, for example, experienced devastating famines, waves of pillaging mercenaries, peasant revolts, religious turmoil and a plague that wiped out as much as half the population in four years. The evidence suggests that all this resulted in mass convulsions of anxiety, a period of psychic torment in which, as one historian has put it, “the more one knew, the less sense the world made.”

It’s hard to imagine that we have it even close to as bad as that. Yet there is an aspect of anxiety that we clearly have more of than ever before: self-awareness…Anxiety didn’t emerge as a cohesive psychiatric concept until the early 20th century..By 1977, the psychoanalyst Rollo May was noting an explosion in papers, books and studies on the subject.

...we shouldn’t be possessive about our uncertainties, particularly as one of the dominant features of anxiety is its recursiveness. Anxiety begins with a single worry, and the more you concentrate on that worry, the more powerful it gets, and the more you worry. One of the best things you can do is learn to let go: to disempower the worry altogether. If you start to believe that anxiety is a foregone conclusion — if you start to believe the hype about the times we live in — then you risk surrendering the battle before it’s begun.

On Solitude.

Reading a recent New York Times Op-Ed piece by Susan Cain ("The Rise of the New Groupthink") transported me back over 20 years to what I then experienced as a transformative reading of British Psychotherapist Anthony Storr's book "Solitude, a return to the self." It's reading provided me with a my needed validation of my own solitary and introspective nature (preferring to do my work and thinking my myself, even while serving and respecting social groups, such as the laboratory I ran). Storr's book was a reaction against the popular psychotherapies of the 1980s which emphasized intimate interpersonal relationships as the chief, if not the only, source of human happiness. He made a strong case that the life of an average person, not just a familiar list of brilliant scholars and artists such as Beethoven, Kant, Newton, etc., could be greatly enriched more time spent alone.

In a similar vein Cain writes against the current assumption that creativity, particularly in business, requires the collaboration of group of people addressing the problem at hand. Her central illustration describes the origins of the Apple computer, It's creation required the support of a creative group of engineers and Steve Jobs' business sense, but the creative kernel of work and insight that put together the core of the actual hardware and code that ran it was done by Wozniak's solitary effort. Cain notes:

...brainstorming sessions are one of the worst possible ways to stimulate creativity...People in groups tend to sit back and let others do the work; they instinctively mimic others’ opinions and lose sight of their own; and, often succumb to peer pressure... fear of rejection actives the brain's amygdala.

The one important exception to this dismal record is electronic brainstorming, where large groups outperform individuals; and the larger the group the better. The protection of the screen mitigates many problems of group work. This is why the Internet has yielded such wondrous collective creations. Marcel Proust called reading a “miracle of communication in the midst of solitude,” and that’s what the Internet is, too. It’s a place where we can be alone together — and this is precisely what gives it power.

...most humans have two contradictory impulses: we love and need one another, yet we crave privacy and autonomy....To harness the energy that fuels both these drives, we need to move beyond the New Groupthink and embrace a more nuanced approach to creativity and learning. Our offices should encourage casual, cafe-style interactions, but allow people to disappear into personalized, private spaces when they want to be alone. Our schools should teach children to work with others, but also to work on their own for sustained periods of time. And we must recognize that introverts like Steve Wozniak need extra quiet and privacy to do their best work.

Before Mr. Wozniak started Apple, he designed calculators at Hewlett-Packard, a job he loved partly because HP made it easy to chat with his colleagues. Every day at 10 a.m. and 2 p.m., management wheeled in doughnuts and coffee, and people could socialize and swap ideas. What distinguished these interactions was how low-key they were. For Mr. Wozniak, collaboration meant the ability to share a doughnut and a brainwave with his laid-back, poorly dressed colleagues — who minded not a whit when he disappeared into his cubicle to get the real work done.

Chill-out architecture - The use of tree metaphors

I gravitate towards forests and trees (typing right now at a desk that looks out at a large tree canopy on the opposite riverbank) because the vision of green trees under a blue sky is vastly more calming that having to look at the more brown and red tints of modern city structures. (My current Fort Lauderdale location is an extended strip mall only occasionally small bits of nature to intrude). Old pine forests give me the same sheltered feeling as the great cathedrals of Europe.

Thus I am very sympathetic to efforts to argue for a evolutionary or biological basis for these feelings, which appear to be common to most human cultures. E.O. Wilson, the father of "Sociobiology" and evolutionary psychology, has written a book "Biophilia" that essentially argues that our preference for natural scenes is innate, the product of a psychology that evolved in paleolithic times. I would like this to be a correct view, but alas, it is, like most of evolutionary psychology, more like Rudyard Kipling's "Just so Stories" than hard science.

It is one thing to simply note trees as a metaphor for shelter, and thus to find it natural that architectural designs (such as the Metropol Parasol in Seville shown in the picture) that incorporate the tree metaphor would be pleasing to us. It is quite another hang this all on the supposed cognitive neuroscience of embodied cognition, as Sarah Williams Goldhagen, the architecture critic for The New Republic, has done in a rather confused piece. A recent post by Voytek, and the discussion following, point out a number of reservations and relevant points.

Living large - how the powerful overestimate.

From Duguid and Goncalo, their abstract, slightly edited:

In three experiments, we tested the prediction that individuals’ experience of power influences their perceptions of their own height. In the first experiment high power, relative to low power, was associated with smaller estimates of a pole’s height relative to the self, in a second experiment with larger estimates of one’s own height, and in a third experiment with choice of a taller avatar to represent the self in a second-life game . These results emerged regardless of whether power was experientially primed (In the first and third experiments) or manipulated through assigned roles (in the second experiment). Although a great deal of research has shown that more physically imposing individuals are more likely to acquire power, this work is the first to show that powerful people feel taller than they are. The discussion considers the implications for existing and future research on the physical experience of power.

My pushing back against our diffusion into “the cloud”

My son visits over the new year's holiday every year, which gives me the chance to have a "techie" conference with him to see what I've been missing. One of the web applications he mentioned lead me to Ghostery, a web app that installs on your web browser with a cute little pac-man like ghost that shows you who is tracking your web movements and what cookies have been put on your browser (I was rather taken aback to see that I'm tracked by 759 'bugs' and have 412 cookies). The Ghostery App allows you to inactivate them individually or as a group. Even though most of the monitoring of our movements on the web is supposedly for benign marketing purposes, I'm more than happy to turn it all off.

A storm of controversy has risen over Google recent effort to conflate supposedly neutral web searches with its Google Plus social network, so that a search for information on some idea or item might now yield results that include posts, photos, profiles and conversations from Google Plus that are public or were shared privately with the person searching. I go to google for Google for links to expert information, and don't want my search results to be cluttered with friends’ postings. Since I use google for practically everything I do on the web (this blog, mail, calendar, contacts, google+, google voice, etc.), this cross linking of my search results and my google+ account is in fact happening. Fortunately, you can turn off this google+ feature by going to the gear-shaped options icon at the top right of google search results, selecting "Search settings," scrolling down till you see "Personal results" and tick the box next to "Do not use personal results."

Remembering a rosy future.

Here is a fascinating tidbit from Dan Schacter's laboratory. When we imagine events in the future, our subsequent recall of negative simulations fades more rapidly than our recall of positive ones.:

Mental simulations of future experiences are often concerned with emotionally arousing events. Although it is widely believed that mental simulations enhance future behavior, virtually nothing is known about how memory for these simulations changes over time or whether simulations of emotional experiences are especially well remembered. We used a novel paradigm that combined recently developed methods for generating simulations of future events and well-established procedures for testing memory to examine the retention of positive, negative, and neutral simulations over delays of 10 min and 1 day. We found that at the longer delay, details associated with negative simulations were more difficult to remember than details associated with positive or neutral simulations. We suggest that these effects reflect the influence of the fading-affect bias, whereby negative reactions fade more quickly than positive reactions, and that this influence results in a tendency to remember a rosy simulated future. We discuss implications of our findings for individuals with affective disorders, such as depression and anxiety.

(Schacter, in the Harvard Psychology department, is a prolific memory researcher, and is author of such popular books as "The Seven Sins of Memory: How the Mind Forgets and Remembers." as well as coauthor, along with Gilbert and Wegner, of a really excellent introductory college Psychology text.)

Our bias against creativity

In principle we are all for creativity, but, when faced with the prospect of actually altering our behavior or opinions we falter. Mueller et al suggest that this is a covert, largely unconscious process regulated by how uncertain we feel. Their results show that regardless of the degree to which people are open minded, when they feel motivated to reduce uncertainty (either because they have an immediate goal of reducing uncertainty or they feel uncertain generally), they may experience more negative associations with creativity, which results in lower evaluations of a creative idea. Their findings imply an irony. Other research has shown that uncertainty spurs the search for and generation of creative ideas, yet these findings reveal that uncertainty also makes people less able to recognize creativity, perhaps when they need it most. Here is the abstract.:

People often reject creative ideas, even when espousing creativity as a desired goal. To explain this paradox, we propose that people can hold a bias against creativity that is not necessarily overt and that is activated when people experience a motivation to reduce uncertainty. In two experiments, we manipulated uncertainty using different methods, including an uncertainty-reduction prime. The results of both experiments demonstrated the existence of a negative bias against creativity (relative to practicality) when participants experienced uncertainty. Furthermore, this bias against creativity interfered with participants’ ability to recognize a creative idea. These results reveal a concealed barrier that creative actors may face as they attempt to gain acceptance for their novel ideas.

IQ scores are malleable.

Brinch and Galloway do a rather clean demonstration that contests the common notion that education has little effect on IQ. Here is the abstract and one figure from the paper.:

Although some scholars maintain that education has little effect on intelligence quotient (IQ) scores, others claim that IQ scores are indeed malleable, primarily through intervention in early childhood. The causal effect of education on IQ at later ages is often difficult to uncover because analyses based on observational data are plagued by problems of reverse causation and self-selection into further education. We exploit a reform that increased compulsory schooling from 7 to 9 y in Norway in the 1960s to estimate the effect of education on IQ. We find that this schooling reform, which primarily affected education in the middle teenage years, had a substantial effect on IQ scores measured at the age of 19 y.

Average IQ and education by time to reform.

BioDigitalHuman - You've got to check out this site!

I've just spent the last two hours marveling at the incredibly elegant 3-D human anatomy website developed by BioDigital Systems (pointed to by Natashe Singer's article). (I'm finding the 3-D graphics work on either Firefox or Chrome, but not both, depending of which of my MacBook Pro laptops I'm using.  Go figure.  I use Apple computers, so can't comment on Microsoft Explorer.) You can view gross to detailed levels of skeletal, muscular, nervous, endocrine, cardiovascular, digestive, etc., systems. A click on a structure brings up a detailed description along with relevant clinical issues. I focused first on the brain (finding it helps if you first toggle off viewing the skeleton system skull that covers it. Duh!) You can zoom in and out, performing 3-D rotations to see precisely where structures are. Asking for smaller internal structure like the pituitary, or left or right amygdala, takes you to their internal location, and you can zoom in and out to appreciate how to get there. The transitions from external to internal brain structures are crude and jerky at this point, and I hope the developers will be adding more fine structure and smoother transitions during zooming. (It will take a massive amount of work to do this.)

I moved next to the muscular system, particularly around the knee joints (whose malfunctions in my case over the past year have convinced me I may no longer a teenager, in fact might be "old"). I found a more clear view of the muscles and their insertions that might underlie the pain than I've been able to get from several doctor's appointments.

Happy hunting!

Classic versus modern violins: beauty in the eye of the beholder?

It is a truism among musicians that no modern violin can, or ever will, approach the perfection of the instruments crafted by Renaissance violin makers such as Stradivari or Guarneri del Gesù in the late 17th and early 18th centuries. Nichlas Wade describes an interesting test published in PNAS that aims to determine if this is in fact the case. Violinists attending an international competition were asked to wear goggles (so they could not identify the instruments they were playing) and play three classic (a Guarneri and two Stradivari instruments) and three high quality modern violins. (It has been as pastime of physicists for years to analyze the sound qualities of old violins and devise construction techniques that could reproduce them in modern instruments.)

...participants in Dr. Fritz’s test could not reliably distinguish the old instruments from modern violins. Only 8 of the 21 subjects chose an old violin as the one they’d like to take home. In the old-to-new comparison, a Stradivarius came in last and a new violin as the most preferred.

The results are clear, even though there was grumbling from other players that the test was performed in a hotel room rather than a concert hall, so projection qualities of the instruments might not have been appreciated.

This reminds me of the numerous blind taste tests involving hundreds of people have shown no correlation between the price of wines costing from $1.50 to $150 and their reported taste. In fact, I've done a posting on the neural correlates of this effect (see also this related posting).

Are the Humanities becoming the “Animal Sciences”

A theme of my "Biology of Mind" course at the University of Wisconsin and the book of that title that I generated from my lecture notes was that our understanding of almost any aspect of our culture and literature could be enhanced by knowledge of its biological underpinnings. As more or and more of the cognitive faculties once assumed to be unique to humans are found in animals (aspects of math, language, tool use, the roots of morality) the citadel of the Humanities has increasingly taken note and an
article by James Gorman points to the consequences of this: a array of courses that bridge animal studies and human animal interactions.

This spring, freshmen at Harvard can take “Human, Animals and Cyborgs.” Last year Dartmouth offered “Animals and Women in Western Literature: Nags, Bitches and Shrews.” New York University offers “Animals, People and Those in Between.”

The existence of an emerging scholarly community is reflected by the recent formation of the Animals and Society Institute, which lists more than 100 college level courses that fit under the broad banner of animal studies. Previously ignored ethical issues in the treatment of animals are being scrutinized. The human-animal divide is being eroded as humans increasingly realize they too are animals, and subject to the same natural forces. Any cultural trend that injects just a bit more humility into us humans has to be a good thing.

Structural changes in adult brains caused by acquiring knowledge

A number of reports have appeared over the past 20 years suggesting that the hippocampus region of the brain involved in place memory is larger than normal in London Taxi drivers (who must pass a memory test of London streets to become licensed taxi drivers). Woollett and Maguire have now examined this more carefully. Their summaries:

-Trainee taxi drivers in London spend 3–4 years learning the city's layout
-We assessed the brain and memory of trainees before and after this long training
-Those who qualified experienced increased gray matter in posterior hippocampus
-Successful qualification was also associated with changes in memory profile

The last decade has seen a burgeoning of reports associating brain structure with specific skills and traits. Although these cross-sectional studies are informative, cause and effect are impossible to establish without longitudinal investigation of the same individuals before and after an intervention. Several longitudinal studies have been conducted; some involved children or young adults, potentially conflating brain development with learning, most were restricted to the motor domain, and all concerned relatively short timescales (weeks or months). Here, by contrast, we utilized a unique opportunity to study average-IQ adults operating in the real world as they learned, over four years, the complex layout of London's streets while training to become licensed taxi drivers. In those who qualified, acquisition of an internal spatial representation of London was associated with a selective increase in gray matter (GM) volume in their posterior hippocampi and concomitant changes to their memory profile. No structural brain changes were observed in trainees who failed to qualify or control participants. We conclude that specific, enduring, structural brain changes in adult humans can be induced by biologically relevant behaviors engaging higher cognitive functions such as spatial memory, with significance for the “nature versus nurture” debate.

Can ignorance promote democracy?

It is easy to despair over the continuing decay in the intelligence and rationality of American voters, and worry about their susceptibility to manipulation by loud voices offering simplistic solutions. Past work has suggested that when many individuals (human voters, flocks of birds, schools of fish) must come together to make a single collective decision, a strongly opinionated minority (tea party anyone?), might be able to exert disproportional pressure on the decision-making process. Couzin et al. develop a theoretical model in which uninformed individuals inhibit the influence of a strongly opinionated minority, returning control to the numerical majority, and in experiments on the shiner, a schooling fish, show the utility of their model. In the presence of an intransigent (and not proselytizing) minority uninformed individuals tend to adopt the opinions of those around them, amplifying the majority opinion and preventing erosion by the intransigent minority. Thus, adding uninformed individuals to a group can facilitate fair representation during the process of information integration. Here is the abstract:

Conflicting interests among group members are common when making collective decisions, yet failure to achieve consensus can be costly. Under these circumstances individuals may be susceptible to manipulation by a strongly opinionated, or extremist, minority. It has previously been argued, for humans and animals, that social groups containing individuals who are uninformed, or exhibit weak preferences, are particularly vulnerable to such manipulative agents. Here, we use theory and experiment to demonstrate that, for a wide range of conditions, a strongly opinionated minority can dictate group choice, but the presence of uninformed individuals spontaneously inhibits this process, returning control to the numerical majority. Our results emphasize the role of uninformed individuals in achieving democratic consensus amid internal group conflict and informational constraints.

Dynamics of improvising together.

In a previous life (when I was a 30-something) I frequently participated in dance improvisation sessions sponsored by either the Univ. of Wisc. Dance Department or local dance groups. One of the basic exercises was 'mirroring', two dancers generating novel movements by attempting to spontaneously generate matching movements. This worked much better when participants were equal, rather than one being designated the leader. Here is an interesting bit of work by Noy et al. describing why that was the case:

Joint improvisation is the creative action of two or more people without a script or designated leader. Examples include improvisational theater and music, and day-to-day activities such as conversations. In joint improvisation, novel action is created, emerging from the interaction between people. Although central to creative processes and social interaction, joint improvisation remains largely unexplored due to the lack of experimental paradigms. Here we introduce a paradigm based on a theater practice called the mirror game. We measured the hand motions of two people mirroring each other at high temporal and spatial resolution. We focused on expert actors and musicians skilled in joint improvisation. We found that players can jointly create novel complex motion without a designated leader, synchronized to less than 40 ms. In contrast, we found that designating one player as leader deteriorated performance: The follower showed 2–3 Hz oscillation around the leader's smooth trajectory, decreasing synchrony and reducing the range of velocities reached. A mathematical model suggests a mechanism for these observations based on mutual agreement on future motion in mirrored reactive–predictive controllers. This is a step toward understanding the human ability to create novelty by improvising together.

Have a scary memory? Erase it with prozac plus psychotherapy.

Numerous clinical studies by now have shown that a combination of antidepressant medication and psychological treatment works better for mood disorders than either therapy on its own. Karpova et al. have now ferreted out the mechanisms that might underlie this fact by investigating the effect of fluoxetine (Prozac) on fear-conditioned memories in mice. Fluoxetine accelerated extinction of fear responses, and together with extinction training disrupted fear renewal and fear reinstatement, but neither treatment by itself produced long term fear extinction. Their results suggest that fluoxetine reactivates plasticity within the amygdala, which, in combination with extinction training, can lead to the erasure of conditioned fear responses. Here is their abstract:

Antidepressant drugs and psychotherapy combined are more effective in treating mood disorders than either treatment alone, but the neurobiological basis of this interaction is unknown. To investigate how antidepressants influence the response of mood-related systems to behavioral experience, we used a fear-conditioning and extinction paradigm in mice. Combining extinction training with chronic fluoxetine, but neither treatment alone, induced an enduring loss of conditioned fear memory in adult animals. Fluoxetine treatment increased synaptic plasticity, converted the fear memory circuitry to a more immature state, and acted through local brain-derived neurotrophic factor. Fluoxetine-induced plasticity may allow fear erasure by extinction-guided remodeling of the memory circuitry. Thus, the pharmacological effects of antidepressants need to be combined with psychological rehabilitation to reorganize networks rendered more plastic by the drug treatment.

Our genes and our behavior, a paradigm shift in our understanding

I thought it would be interesting to pass on two recent items I've come across. The first is the paper by Schultz et al. (also, see commentary by Wade.) that challenges some of the leading theories of social behavior (that stress environment, larger groups sizes forcing larger more intelligent brains, stepwise progression to complexity,etc.) to argue that genetic determinants force primate species, including ours, into whatever social structures they inherit.

Compare this with the proposed article from Behavioral and Brain Sciences "Behavior genetics and post genomics", by Charney (PDF download here), which points to the much more tortuous road from genotype to phenotype. Here is his abstract:

The science of genetics is undergoing a paradigm shift. Recent discoveries, including the activity of retrotransposons, the extent of copy number variations, somatic and chromosomal mosaicism, and the nature of the epigenome as a regulator of DNA expressivity, are challenging a series of dogmas concerning the nature of the genome and the relationship between genotype and phenotype. DNA, once held to be the unchanging template of heredity, now appears subject to a good deal of environmental change; considered to be identical in all cells and tissues of the body, there is growing evidence that somatic mosaicism is the normal human condition; and treated as the sole biological agent of heritability, we now know that the epigenome, which regulates gene expressivity, can be inherited via the germline. These developments are particularly significant for behavior genetics for at least three reasons: First, these phenomena appear to be particularly prevalent in the human brain, and likely are involved in much of human behavior; second, they have important implications for the validity of heritability and gene association studies, the methodologies that largely define the discipline of behavior genetics; and third, they appear to play a critical role in development during the perinatal period, and in enabling phenotypic plasticity in offspring in particular. I examine one of the central claims to emerge from the use of heritability studies in the behavioral sciences, the principle of "minimal shared maternal effects," in light of the growing awareness that the maternal perinatal environment is a critical venue for the exercise of adaptive phenotypic plasticity. This consideration has important implications for both developmental and evolutionary biology.

Friends with benefits - pet ownership and well-being

My two abyssinian cats and I agree with the (obvious) results of this study by Harmon-Jones et al.:

Social support is critical for psychological and physical well-being, reflecting the centrality of belongingness in our lives. Human interactions often provide people with considerable social support, but can pets also fulfill one's social needs? Although there is correlational evidence that pets may help individuals facing significant life stressors, little is known about the well-being benefits of pets for everyday people. Study 1 found in a community sample that pet owners fared better on several well-being (e.g., greater self-esteem, more exercise) and individual-difference (e.g., greater conscientiousness, less fearful attachment) measures. Study 2 assessed a different community sample and found that owners enjoyed better well-being when their pets fulfilled social needs better, and the support that pets provided complemented rather than competed with human sources. Finally, Study 3 brought pet owners into the laboratory and experimentally demonstrated the ability of pets to stave off negativity caused by social rejection. In summary, pets can serve as important sources of social support, providing many positive psychological and physical benefits for their owners.

Local Jekyll and global Hyde - duality of face perception

Miellet et al. make the curious observation that we can identify faces with either focused foveal global (peripheral) vision:

The main concern in face-processing research is to understand the processes underlying the identification of faces. In the study reported here, we addressed this issue by examining whether local or global information supports face identification. We developed a new methodology called “iHybrid.” This technique combines two famous identities in a gaze-contingent paradigm, which simultaneously provides local, foveated information from one face and global, complementary information from a second face. Behavioral face-identification performance and eye-tracking data showed that the visual system identified faces on the basis of either local or global information depending on the location of the observer’s first fixation. In some cases, a given observer even identified the same face using local information on one trial and global information on another trial. A validation in natural viewing conditions confirmed our findings. These results clearly demonstrate that face identification is not rooted in a single, or even preferred, information-gathering strategy.

Figure - Procedure used to create iHybrid faces. The spatial frequencies (SFs) of two original face images (illustrated here with Brad Pitt and William H. Macy) were decomposed separately into four nonoverlapping SF bands of 1 octave each (<3, 3–6, 6–12, >12 cycles per degree of visual angle). A Gaussian window (SD = 25 pixels, ~1° of visual angle) was then centered on every potential fixation location on each face; this procedure formed a lattice of 5- × 5-pixel cells covering the original 260 × 260 image. When an observer fixated on the stimulus, the local information across the four SF bands for one identity was extracted through the Gaussian window at that location, and the complementary global SF information was extracted from the other identity. The sum of the complementary, fixation-dependent identities formed the iHybrid stimulus. In the example illustrated here, the dashed red line indicates a fixation location at the left eye; local SF information was extracted from this location in the image of Brad Pitt, and the complementary SF information was taken from the image of William H. Macy. An observer who identifies the resulting face as Brad Pitt is using local information, and an observer who identifies this face as William H. Macy is using global information.

Leaning to the left makes an object seem smaller.

From Eerland et al., here is yet another neat example of embodied cognition, how a body state can influence "objective" estimations:

In two experiments, we investigated whether body posture influences people’s estimation of quantities. According to the mental-number-line theory, people mentally represent numbers along a line with smaller numbers on the left and larger numbers on the right. We hypothesized that surreptitiously making people lean to the right or to the left would affect their quantitative estimates. Participants answered estimation questions while standing on a Wii Balance Board. Posture was manipulated within subjects so that participants answered some questions while they leaned slightly to the left, some questions while they leaned slightly to the right, and some questions while they stood upright. Crucially, participants were not aware of this manipulation. Estimates were significantly smaller when participants leaned to the left than when they leaned to the right.

Musicians use both sides of their brains more frequently.

A colleague pointed me to this interesting (to me, because I'm a pianist) work by Sohee Park's laboratory at Vanderbilt. Their central finding is that professionally trained musicians more effectively use divergent thinking (the ability to come up with new solutions to open-ended, multifaceted problems, or thinking 'outside of the box'). Creative thinking was tested both with written word association test and by asking subjects to make up new functions for a variety of household objects. Brain activity was measured by near infrared spectroscopy (NIRS), a noninvasive neuroimaging method that allows in-vivo measurement of changes in the concentrations of oxygenated hemoglobin and deoxygenated hemoglobin in the cortex. They suggest that musician's elevated use of both brain hemispheres may be related to having to use two hands independently, as well as follow multiple voices on musical scores. Folley, one of the authors, noted "“Musicians may be particularly good at efficiently accessing and integrating competing information from both hemispheres...Instrumental musicians often integrate different melodic lines with both hands into a single musical piece, and they have to be very good at simultaneously reading the musical symbols, which are like left-hemisphere-based language, and integrating the written music with their own interpretation, which has been linked to the right hemisphere.” Here is the PDF of their article, and here is the abstract:

Empirical studies of creativity have focused on the importance of divergent thinking, which supports generating novel solutions to loosely defined problems. The present study examined creativity and frontal cortical activity in an externally-validated group of creative individuals (trained musicians) and demographically matched control participants, using behavioral tasks and near-infrared spectroscopy (NIRS). Experiment 1 examined convergent and divergent thinking with respect to intelligence and personality. Experiment 2 investigated frontal oxygenated and deoxygenated hemoglobin concentration changes during divergent thinking with NIRS. Results of Experiment 1 indicated enhanced creativity in musicians who also showed increased verbal ability and schizotypal personality but their enhanced divergent thinking remained robust after co-varying out these two factors. In Experiment 2, NIRS showed greater bilateral frontal activity in musicians during divergent thinking compared with nonmusicians. Overall, these results suggest that creative individuals are characterized by enhanced divergent thinking, which is supported by increased frontal cortical activity.

Good minus God - distrust of atheists

Gervais et al offer yet another study on us poor atheists. I follow their abstract with some comments on such studies:

Recent polls indicate that atheists are among the least liked people in areas with religious majorities (i.e., in most of the world). The sociofunctional approach to prejudice, combined with a cultural evolutionary theory of religion's effects on cooperation, suggest that anti-atheist prejudice is particularly motivated by distrust. Consistent with this theoretical framework, a first study using a broad sample of American adults revealed that distrust characterized anti-atheist prejudice but not anti-gay prejudice. In subsequent studies, distrust of atheists generalized even to participants from more liberal, secular populations. In three further studies description of a criminally untrustworthy individual was seen as comparably representative of atheists and rapists but not representative of Christians, Muslims, Jewish people, feminists, or homosexuals. In addition, results were consistent with the hypothesis that the relationship between belief in God and atheist distrust was fully mediated by the belief that people behave better if they feel that God is watching them. In implicit measures, participants strongly associated atheists with distrust, and belief in God was more strongly associated with implicit distrust of atheists than with implicit dislike of atheists. Finally, atheists were systematically socially excluded only in high-trust domains; belief in God, but not authoritarianism, predicted this discriminatory decision-making against atheists in high trust domains. These 6 studies are the first to systematically explore the social psychological underpinnings of anti-atheist prejudice, and converge to indicate the centrality of distrust in this phenomenon.

In the New York Times online Opinionator, Louise Anthony makes some interesting points about such studies. A few brief clips:

I gather that many people believe that atheism implies nihilism — that rejecting God means rejecting morality. A person who denies God, they reason, must be, if not actively evil, at least indifferent to considerations of right and wrong. After all, doesn’t the dictionary list “wicked” as a synonym for “godless?” And isn’t it true, as Dostoevsky said, that “if God is dead, everything is permitted”?

Well, actually — no, it’s not. (And for the record, Dostoevsky never said it was.) Atheism does not entail that anything goes.

We “moralistic atheists” do not see right and wrong as artifacts of a divine protection racket. Rather, we find moral value to be immanent in the natural world, arising from the vulnerabilities of sentient beings and from the capacities of rational beings to recognize and to respond to those vulnerabilities and capacities in others...many theists, like many atheists, believe that moral value is inherent in morally valuable things. Things don’t become morally valuable because God prefers them; God prefers them because they are morally valuable.

Prosocial behavior as intrinsic to our brains in absence of social pressure

Zaki and Mitchell question the evolutionary and economic models assume that humans are fundamentally selfish and perform altruistic behaviors only because of social pressure:

Standard economic and evolutionary models assume that humans are fundamentally selfish. On this view, any acts of prosociality—such as cooperation, giving, and other forms of altruism—result from covert attempts to avoid social injunctions against selfishness. However, even in the absence of social pressure, individuals routinely forego personal gain to share resources with others. Such anomalous giving cannot be accounted for by standard models of social behavior. Recent observations have suggested that, instead, prosocial behavior may reflect an intrinsic value placed on social ideals such as equity and charity. Here, we show that, consistent with this alternative account, making equitable interpersonal decisions engaged neural structures involved in computing subjective value, even when doing so required foregoing material resources. By contrast, making inequitable decisions produced activity in the anterior insula, a region linked to the experience of subjective disutility. Moreover, inequity-related insula response predicted individuals’ unwillingness to make inequitable choices. Together, these data suggest that prosocial behavior is not simply a response to external pressure, but instead represents an intrinsic, and intrinsically social, class of reward.

Single nucleotide change in oxytocin receptor gene decreases stress relief by social support.

In recent years, the human oxytocin system has been increasingly studied as essential to our prosocial behavior and also buffering stress. One single nucleotide variation in the oxytocin receptor (OXTR) gene named rs53576 (G/A) involves switching between the G and A nucleotides. THe A allel of rs5376 has been associated with lower empathy, reduced reward dependence, lower optimism and self-esteem, and negative affect. Now Chen et al. find a further correlation; individuals with two copies of AA do not show lower cortisol responses to stress after social support. Here is their abstract:

The neuropeptide oxytocin has played an essential role in the regulation of social behavior and attachment throughout mammalian evolution. Because recent studies in humans have shown that oxytocin administration reduces stress responses and increases prosocial behavior, we investigated whether a common single nucleotide polymorphism (rs53576) in the oxytocin receptor gene (OXTR) might interact with stress-protective effects of social support. Salivary cortisol samples and subjective stress ratings were obtained from 194 healthy male participants before, during, and after a standardized psychosocial laboratory stress procedure. Participants were randomly assigned either to prepare alone or to receive social support from their female partner or close female friend while preparing for the stressful task. Differential stress responses between the genotype groups were observed depending on the presence or absence of social support. Only individuals with one or two copies of the G allele of rs53576 showed lower cortisol responses to stress after social support, compared with individuals with the same genotype receiving no social support. These results indicate that genetic variation of the oxytocin system modulates the effectiveness of positive social interaction as a protective buffer against a stressful experience.

A face only an investor could love...

Here is a quirky item, a bit of a stretch but curious. Given that psychological traits are thought to relate to effective leadership, Wong et al. ask whether any simple physical traits in a leader might correlate with a firms financial performance. They determined the the face width to height ratio of male leaders of 55 Fortune 500 organizations that formed part of the sample of a larger study examining the relationships among CEO characteristics, top-management-team1 processes, and organizational outcomes between 1996 and 2002:

Researchers have theorized that innate personal traits are related to leadership success. Although links between psychological characteristics and leadership success have been well established, research has yet to identify any objective physical traits of leaders that predict organizational performance. In the research reported here, we identified leaders’ facial structure as a specific physical trait that correlates with organizational performance. Specifically, we found that firms whose male CEOs have wider faces (relative to facial height) achieve superior financial performance. Decision-making dynamics within a firm’s leadership team moderate this effect, such that the relationship between a given CEO’s facial measurements and his firm’s financial performance is stronger in firms with cognitively simple leadership teams.

Figure - Industry-adjusted return on assets (ROA) as a function of the cognitive complexity of firms’ top management teams (TMTs) and CEOs’ facial width-to-height ratio (WHR). The slopes illustrated in this graph were calculated using the minimum (low) and maximum (high) values for cognitive complexity and CEO facial WHR. USD = U.S. dollars.

Our mindreading of another person depends on how much skin we see!

This interesting piece in the Journal of Personality and Social Psychology makes observations on how our mindreading, or inferring someone's nature, depends on how much of them we are seeing. From the introduction:

Do people’s mental capacities fundamentally change when they remove a sweater? This seems absurd: How could removing a piece of clothing change one’s capacity for acting or feeling? In six studies, however, we show that taking off a sweater—or otherwise revealing flesh—can significantly change the way a mind is perceived. In this article, we suggest that the kind of mind ascribed to another person depends on the relative salience of his or her body—that the perceived capacity for both pain and planned action depends on whether someone wears a sweater or tank-top.

The abstract:

According to models of objectification, viewing someone as a body induces de-mentalization, stripping away their psychological traits. Here evidence is presented for an alternative account, where a body focus does not diminish the attribution of all mental capacities but, instead, leads perceivers to infer a different kind of mind. Drawing on the distinction in mind perception between agency and experience, it is found that focusing on someone's body reduces perceptions of agency (self-control and action) but increases perceptions of experience (emotion and sensation). These effects were found in three experiments when comparing targets represented by both revealing versus nonrevealing pictures or by simply directing attention toward physical characteristics. In two further experiments he effect of a body focus on mind perception also influenced moral intuitions, with those represented as a body seen to be less morally responsible (i.e., lesser moral agents) but more sensitive to harm (i.e., greater moral patients). These effects suggest that a body focus does not cause objectification per se but, instead, leads to a redistribution of perceived mind.

Why do humans collaborate so much?

Chimpanzees apparently have the cognitive skills needed to be a good collaborator. They recognize and attend to other's goals and understand how to pick an effective cooperative partner. Yet, they collaborate very little. Tomasello and his colleagues have designed an experiment that shows that problem is one of motivation rather than understanding. They presented human children and chimpanzees with a foraging problem that could be solved equally well either individually or collaboratively. Children chose the teamwork option three quarters of the time. Chimps,in contrast, performed at chance levels, indifferent to whether a conspecific worked with them. Here is a description of the setup in Santos' review:

Participants from both species were presented with the opportunity to obtain food from one of two out-of-reach boards. To get food from the first board, participants had to pull a set of ropes on their own to move the food board closer. To access food from the second board, participants had to work collaboratively with a conspecific partner, pulling the set of ropes simultaneously with their partner to access the food. Participants from both species were then given a choice between the two boards: did they want to work with a partner or would they prefer to operate the board by themselves? The authors found a big difference across the two populations. Children preferred to obtain food using the collaborative board, choosing the teamwork option about three quarters of the time. Chimpanzees, in contrast, performed at chance; they were indifferent to whether another conspecific worked with them to solve this problem, suggesting they're not as motivated to seek out opportunities to work together.

To explore the chimps motivation in more detail:

They presented chimpanzees with a similar foraging problem to that of the previous study, but varied the payoffs across the solitary and collaborative boards. In their first study, they observed that chimpanzees show a striking preference to work by themselves when the pay-offs are equated across the two boards. They then changed the pay-off structure in the next study, allowing chimpanzees to earn more food when they worked with a partner. Only when the relative pay-off from the collaborative board was increased did chimpanzees show the kind of preference that children showed for foraging collaboratively. Chimpanzees, it seems, need a little something extra to work in a team; children are motivated to do it for free.

Video at the speed of light.

The N.Y. Times points to extraordinary work that captures the image of a light pulse moving through an object, vastly faster than previous high speed photography. The technique might replace current ultrasound imaging in medical technology with photon imaging.

Taming human conflicts in the real world

Alexander and Christia provide a social psychology experiment that doesn't use Western undergraduate psychology students as subjects! They were provided the opportunity by a natural experiment that resulted from the consolidation of four Mostar high schools into three, yielding corat-majority, bosniac-majority and heterogeneous ethnic compositions. The students participated in economic experiments that pit an individual's self interest against the welfare of other participants. These others sometimes belong to the same ethnic group, and sometimes not, at integrated as well as segregated schools. This allowed the authors to measure the willingness to cooperate with others:

Whereas altruism drives the evolution of human cooperation, ethno-religious diversity has been considered to obstruct it, leading to poverty, corruption, and war. We argue that current research has failed to properly account for the institutional environment and how it affects the role diversity plays. The emergence of thriving, diverse communities throughout human history suggests that diversity does not always lead to cooperation breakdown. We conducted experiments in Mostar, Bosnia-Herzegovina with Catholic Croats and Muslim Bosniaks at a critical historic moment in the city’s postwar history. Using a public goods game, we found that the ability to sanction is key to achieving cooperation in ethno-religiously diverse groups, but that sanctions succeed only in integrated institutional environments and fail in segregated ones. Hence, we show experimentally for the first time in a real-life setting that institutions of integration can unleash human altruism and restore cooperation in the presence of diversity.

Our biological immune system activates our behavioral immune system.

Viewing disease cues (skin lesions, someone sneezing) leads people to display a heightened biological immune response (for example, stimulated production of cytokine interleukin-6). Miller and Maner now provide evidence for the converse: Activation of the biological immune system promotes activation of the behavioral immune system. Their abstract:

Activation of the behavioral immune system has been shown to promote activation of the biological immune system. The current research tested the hypothesis that activation of the biological immune system (as a result of recent illness) promotes activation of the behavioral immune system. Participants who had recently been ill, and had therefore recently experienced activation of their biological immune system, in one study displayed heightened attention to disfigured individuals, and in a second study showed avoidance — cognitive and behavioral processes reflecting activation of the behavioral immune system. These findings shed light on the interactive nature of biological and psychological mechanisms designed to help people overcome the threat of disease.