Wednesday, February 29, 2012

The map in our head is oriented north.

Interesting observations from Julia Frankenstein et al.:

We examined how a highly familiar environmental space—one’s city of residence—is represented in memory. Twenty-six participants faced a photo-realistic virtual model of their hometown and completed a task in which they pointed to familiar target locations from various orientations. Each participant’s performance was most accurate when he or she was facing north, and errors increased as participants’ deviation from a north-facing orientation increased. Pointing errors and latencies were not related to the distance between participants’ initial locations and the target locations. Our results are inconsistent with accounts of orientation-free memory and with theories assuming that the storage of spatial knowledge depends on local reference frames. Although participants recognized familiar local views in their initial locations, their strategy for pointing relied on a single, north-oriented reference frame that was likely acquired from maps rather than experience from daily exploration. Even though participants had spent significantly more time navigating the city than looking at maps, their pointing behavior seemed to rely on a north-oriented mental map.
Added note: Check out this nice summary by Frankenstein in the NYTimes.

Tuesday, February 28, 2012

Early maternal support predicts larger brain volumes at school age.

Luby et al. offer a compelling study showing the importance of maternal nuturing in young humans.Maternal support is predictive of hippocampus volume measured at school age. From their introduction:

Animal studies have shown that maternal nurturance...promotes adaptive programming of the hypothalamic–pituitary–adrenal axis stress response and hippocampal development. Improvements in the capacity for stress modulation have been shown to be related to epigenetic modifications whereby methylation of multiple genes results in changes in gene expression for glucocorticoid and mineralcorticoid receptors. These changes are associated with increases in dendritic branching and neurogenesis and related increases in hippocampal volumes. Consistent with this phenomenon and conversely, the stress of early maternal deprivation has been shown to have negative effects on this cascade. A similar relationship between early nurturance and stress modulation has also been reported in nonhuman primates.
Their abstract:
Early maternal support has been shown to promote specific gene expression, neurogenesis, adaptive stress responses, and larger hippocampal volumes in developing animals. In humans, a relationship between psychosocial factors in early childhood and later amygdala volumes based on prospective data has been demonstrated, providing a key link between early experience and brain development. Although much retrospective data suggests a link between early psychosocial factors and hippocampal volumes in humans, to date there has been no prospective data to inform this potentially important public health issue. In a longitudinal study of depressed and healthy preschool children who underwent neuroimaging at school age, we investigated whether early maternal support predicted later hippocampal volumes. Maternal support observed in early childhood was strongly predictive of hippocampal volume measured at school age. The positive effect of maternal support on hippocampal volumes was greater in nondepressed children. These findings provide prospective evidence in humans of the positive effect of early supportive parenting on healthy hippocampal development, a brain region key to memory and stress modulation.

Monday, February 27, 2012

How to get the rich to share their marbles.

Jonathan Haidt does a nice job of bringing contemporary relevance to Tomasello and colleagues' work comparing and contrasting the social behaviors of young humans and chimpanzees. (As these two previous MindBlog posts show (1,2), this laboratory has been carpet bombing the journals with articles in this vein.)

Pretend you’re a three-year-old, exploring an exciting new room full of toys. You and another child come up to a large machine that has some marbles inside, which you can see. There’s a rope running through the machine and the two ends of the rope hang out of the front, five feet apart. If you or your partner pulls on the rope alone, you just get more rope. But if you both pull at the same time, the rope dislodges some marbles, which you each get to keep. The marbles roll down a chute, and then they divide: one rolls into the cup in front of you, three roll into the cup in front of your partner...In this situation, where both kids have to pull for anyone to get marbles, the children equalize the wealth about 75% of the time, with hardly any conflict. Either the “rich” kid hands over one marble spontaneously or else the “poor” kid asks for one and his request is immediately granted. (Chimpanzees doing tasks similar to this one do not share the spoils, in any of the conditions. They just grab what they can, regardless of who did what.)
A slight variation ..reveals a deep truth. Things start off just as in the first condition: you and your partner see two ropes hanging out of the machine. But as you start tugging it becomes clear that they are two separate ropes. You pull yours, and one marble rolls out into your cup. Your partner pulls the other rope, and is rewarded with three marbles...What happens next?...For the most part, it’s pullers-keepers. Even though you and your partner each did the same work (rope pulling) at more or less the same time, you both know that you didn’t really collaborate to produce the wealth. Only about 30% of the time did the kids work out an equal split. In other words, the “share-the-spoils” button is not pressed by the mere existence of inequality. It is pressed when two or more people collaborated to produce a gain. Once the button is pressed in both brains, both parties willingly and effortlessly share.
Haidt argues that Obama's prescription for curing the economy fails to press the "share-the-spoils", which might happen if he could frame his statements to make Americans perceive the economy as a giant collaborative project, as happened for the generations that went through the great depression and the second world war (share-the-sacrifice). Instead,
Obama promised he would not raise taxes on anyone but the rich. He and other Democrats have also vowed to “protect seniors” from cuts, even though seniors receive the vast majority of entitlement dollars. The president is therefore in the unenviable position of arguing that we’re in big trouble and so a small percentage of people will have to give more, but most people will be protected from sacrifice. This appeal misses the shared-sacrifice button completely. It also fails to push the share-the-spoils button. When people feel that they’re all pulling on different ropes, they don’t feel entitled to a share of other people’s wealth, even when that wealth was acquired by luck.

Friday, February 24, 2012

Cognitive dissonance reduction in conservative and liberal Christians

Ross et al. offer an interesting study showing how the answers of conservative and liberal Christians to the question "What would a contemporary Jesus do?" reduces the cognitive dissonance of their own opinions:

The present study explores the dramatic projection of one's own views onto those of Jesus among conservative and liberal American Christians. In a large-scale survey, the relevant views that each group attributed to a contemporary Jesus differed almost as much as their own views. Despite such dissonance-reducing projection, however, conservatives acknowledged the relevant discrepancy with regard to “fellowship” issues (e.g., taxation to reduce economic inequality and treatment of immigrants) and liberals acknowledged the relevant discrepancy with regard to “morality” issues (e.g., abortion and gay marriage). However, conservatives also claimed that a contemporary Jesus would be even more conservative than themselves on the former issues whereas liberals claimed that Jesus would be even more liberal than themselves on the latter issues. Further reducing potential dissonance, liberal and conservative Christians differed markedly in the types of issues they claimed to be more central to their faith. A concluding discussion considers the relationship between individual motivational processes and more social processes that may underlie the present findings, as well as implications for contemporary social and political conflict.

Thursday, February 23, 2012

Desperately seeking simplicity.

The Harvard Business Review blog network has an article by Chris Zook, who is co-head of the Global Strategy Practice at Bain & Company (Now why does that name sound familiar, I wonder!!). I thought it worthwhile to abstract and paraphrase his thoughts - his comments derive from a theme that was omnipresent at the recent World Economic Forum in Davos:

that while events are unfolding in the world at an accelerating pace, increasingly complex institutions are less and less able to deal with them.
The problem seems
...not so much identifying what needed to be done as the lack of a plan for making the changes quickly enough.
In a survey, hundreds of leaders and executives...
...say that they do not face inadequate opportunities. Rather, their biggest barrier by far (about 85% of the time) relates to the internal complexity of their organizations and the management of their energy against that...a multi-year study of the root causes of enduring success...found an increasing premium to simplicity in the world of today — not just simplicity of organization, but more fundamentally to an essential simplicity at the heart of strategy itself...an inherent advantage in dealing with... faster moving markets and increased internal complexity due to ability to keep things simpler and more transparent than their rivals...companies who seemed best at creating enduring competitive advantage seemed to be able to maintain a simplicity at their core (think of companies like IKEA, Nike, or Vanguard for instance — very large in size, but with a clarity of strategy and purpose that jumps out at you).
This has its own parallel in the three attributes of great leaders of the future outlined in a talk by Daniel Goleman (Author of Emotional Intelligence):
1) authenticity and sharp clarity of purpose, 2) empathy and the ability to relate to people at the "front line" levels, and 3) self-awareness and humility to constantly question and adapt.

Wednesday, February 22, 2012

An App for your anxiety...

Continuing in the thread of yesterdays post about a science App, I should mention the blip of interest (and controversy) over the putative appearance of an array of 'therapists in your iPhone or Android phone." Benedict Carey offers a recent review. My first reaction is one of complete aversion, thinking that therapy is best cast in a social web of narrative, but as Carey notes:

The upside is that well-designed apps could reach millions of people who lack the means or interest to engage in traditional therapy and need more than the pop mysticism, soothing thoughts or confidence boosters now in use.
It is a fact that some cognitive missteps are of a very mechanical nature, reflecting glitches in stimulus-response matching. Here is a nice example of the app approach:
..cognitive bias modification...seeks to break some of the brain’s bad habits...and is straightforward. Consider people with social anxiety, a kind of extreme shyness that can leave people breathless with dread...many who struggle with such anxiety fixate subconsciously on hostile faces in a crowd of people with mostly relaxed expressions, as if they see only the bad apples in a bushel of mostly good ones...Modifying that bias — that is, reducing it — can interrupt the cascade of thoughts and feelings that normally follow, short-circuiting anxiety, lab studies suggest. In one commonly used program, for instance, people see two faces on the screen, one with a neutral expression and one looking hostile. The faces are stacked one atop the other, and a split-second later they disappear, and a single letter flashes on the screen, in either the top half or the bottom....Users push a button to identify the letter, but this is meaningless; the object is to snap the eyes away from the part of the screen that showed the hostile face, conditioning the brain to ignore those bad apples. That’s all there is to it. Repeated practice, the researchers say, may train the eyes to automatically look away, or the frontal areas of the brain to exercise more top-down control.
Some studies claim positive results with these simple games equivalent to normal therapy, other find no effect. There are the usual issues of whether positive outcomes are a placebo effort or undue attention is being paid to positive data, while negative results are rationalized or downplayed. The strongest claims seem to be for anxiety disorders, not depression.

Tuesday, February 21, 2012

Science of minus 10 Biology iPad App

I've been cruising the annual best science and engineering visualization competition sponsored every year by Science Magazine and the National Science Foundation (see also Wired Magazine account.). I find especially compelling the game "Powers of Ten", which allows players to zoom into a person’s hand, explore the world at different magnifications and learn about the human body:

Monday, February 20, 2012

Our brains as prediction machines - a unified view of mind and action

Anything Andy Clark writes is totally worth reading (I used his charming essay "I am John's brain" when I first began teaching my "Biology of Mind Course" at the University of Wisconsin in the 1990's), and so I pass on this manuscript of an article on which comments are currently being solicited.  It is a fascinating read, lucidly and clearly written. 

"Whatever Next? Predictive Brains, Situated Agents, and the Future of Cognitive Science"

Abstract: Brains, it has recently been argued, are essentially prediction machines. They are bundles of cells that support perception and action by constantly attempting to match incoming sensory inputs with top-down expectations or predictions. This is achieved using a hierarchical generative model that aims to minimize prediction error within a bidirectional cascade of cortical processing.  Such accounts offer a unifying model of perception and action, illuminate the functional role of attention, and may neatly capture the special contribution of cortical processing to adaptive success. The paper critically examines this 'hierarchical prediction machine' approach, concluding that it offers the best clue yet to the shape of a unified science of mind and action. Sections 1 and 2 lay out the key elements and implications of the approach. Section 3 explores a variety of pitfalls and challenges, spanning the evidential, the methodological, and the more properly conceptual. The paper ends (sections 4 and 5) by asking how such approaches might impact our more general vision of mind, experience, and agency. 

Friday, February 17, 2012

Our brain's grasp of metaphors grounded in perception?

Theories of grounded cognition suggest that knowledge is represented in modal systems derived from perception (rather than abstract brain codes) and that cognition depends on perceptual simulations. Conceptual metaphor theory is one approach to grounded cognition which suggests that knowledge is structured by metaphorical mappings from sensory experience. Sathian and colleagues do a interesting experiment in which they find that textural metaphors — phrases like "soft-hearted"— turn on a part of the brain (the parietal operculum) that's important to the sense of touch. This doesn't happen with literal counterparts: "he is wet behind the ears" versus "he is naïve," for example, or "it was a hairy situation" versus "it was a precarious situation."


Figure - Touching actives areas shown in yellow and red. Textural metaphors also trigger a reaction (shown in green and, where overlapping, brown) in the parietal operculum.

It would be interesting to see if a subject's appreciation of a tactile metaphor was compromised by transcranial magnetic stimulation that disrupted activity of the parietal operculum.

Thursday, February 16, 2012

Negative social interactions and body inflammation.

Many studies have proven that social relationships influence our physical health. People who are more socially integrated live longer, and are less likely to have medical problems such as heart attacks and upper respiratory illness. (Cytokines are small protein molecules - peptides - that regulate our inflammatory immune response. While transient inflammatory response due to tissue insult are adaptive and trigger needed immune responses, chronic increases in proinflammatory cytokines IL-6 and TNF-α are linked hypertension, atherosclerosis, coronary heart disease, depression, diabetes, and some cancers.) Chiang et al. now show that these cytokines promoting tissue inflammation appear when we are in socially stressful situations:

Research has consistently documented that social relationships influence physical health, a link that may implicate systemic inflammation. We examined whether daily social interactions predict levels of proinflammatory cytokines IL-6 and the soluble receptor for tumor necrosis factor-α (sTNFαRII) and their reactivity to a social stressor. One-hundred twenty-two healthy young adults completed daily diaries for 8 d that assessed positive, negative, and competitive social interactions. Participants then engaged in laboratory stress challenges, and IL-6 and sTNFαRII were collected at baseline and at 25- and 80-min poststressor, from oral mucosal transudate. Negative social interactions predicted elevated sTNFαRII at baseline, and IL-6 and sTNFαRII 25-min poststressor, as well as total output of sTNFαRII. Competitive social interactions predicted elevated baseline levels of IL-6 and sTNFαRII and total output of both cytokines. These findings suggest that daily social interactions that are negative and competitive are associated prospectively with heightened proinflammatory cytokine activity.

Wednesday, February 15, 2012

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.

Tuesday, February 14, 2012

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.

Monday, February 13, 2012

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.

Friday, February 10, 2012

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.

Thursday, February 09, 2012

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.

Wednesday, February 08, 2012

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.

Tuesday, February 07, 2012

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.

Monday, February 06, 2012

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.

Friday, February 03, 2012

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.)

Thursday, February 02, 2012

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.

Wednesday, February 01, 2012

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?