Monday, October 26, 2009

Meditation training can enhance the stability of our attention

Several groups collaborate to show that meditation training can can significantly affect attention and brain function.
The capacity to stabilize the content of attention over time varies among individuals, and its impairment is a hallmark of several mental illnesses. Impairments in sustained attention in patients with attention disorders have been associated with increased trial-to-trial variability in reaction time and event-related potential deficits during attention tasks. At present, it is unclear whether the ability to sustain attention and its underlying brain circuitry are transformable through training. Here, we show, with dichotic listening task performance and electroencephalography, that training attention, as cultivated by meditation, can improve the ability to sustain attention. Three months of intensive meditation training reduced variability in attentional processing of target tones, as indicated by both enhanced theta-band phase consistency of oscillatory neural responses over anterior brain areas and reduced reaction time variability. Furthermore, those individuals who showed the greatest increase in neural response consistency showed the largest decrease in behavioral response variability. Notably, we also observed reduced variability in neural processing, in particular in low-frequency bands, regardless of whether the deviant tone was attended or unattended. Focused attention meditation may thus affect both distracter and target processing, perhaps by enhancing entrainment of neuronal oscillations to sensory input rhythms, a mechanism important for controlling the content of attention. These novel findings highlight the mechanisms underlying focused attention meditation and support the notion that mental training can significantly affect attention and brain function.

Election night 2008: testosterone level of male McCain voters dropped

Stanton et al. collected saliva samples from 183 study participants before and after the results of the 2008 presidential election were announced. The results show that male Barack Obama voters (winners) had stable post-outcome testosterone levels, whereas testosterone levels dropped in male John McCain and Robert Barr (Libertarian candidate) voters (losers). There were no significant effects in female voters. These results were consistent with earlier studies showing testosterone decreases in male supporters of an athletic team after it loses a game.

Friday, October 23, 2009

Emotional contagion without conscious awareness

Tamietto et al. make the fascinating observation that unseen emotionally expressive facial or body movements (stimuli presented to the blind portion of the visual field of patients with damage to their visual cortex) cause arousal and facial reactions. They suggest that emotional contagion represents affective reactions mediated by visual pathways of old evolutionary origin that bypass cortical vision and allow emotion communication and affect sharing. Here is their abstract:
The spontaneous tendency to synchronize our facial expressions with those of others is often termed emotional contagion. It is unclear, however, whether emotional contagion depends on visual awareness of the eliciting stimulus and which processes underlie the unfolding of expressive reactions in the observer. It has been suggested either that emotional contagion is driven by motor imitation (i.e., mimicry), or that it is one observable aspect of the emotional state arising when we see the corresponding emotion in others. Emotional contagion reactions to different classes of consciously seen and “unseen” stimuli were compared by presenting pictures of facial or bodily expressions either to the intact or blind visual field of two patients with unilateral destruction of the visual cortex and ensuing phenomenal blindness. Facial reactions were recorded using electromyography, and arousal responses were measured with pupil dilatation. Passive exposure to unseen expressions evoked faster facial reactions and higher arousal compared with seen stimuli, therefore indicating that emotional contagion occurs also when the triggering stimulus cannot be consciously perceived because of cortical blindness. Furthermore, stimuli that are very different in their visual characteristics, such as facial and bodily gestures, induced highly similar expressive responses. This shows that the patients did not simply imitate the motor pattern observed in the stimuli, but resonated to their affective meaning. Emotional contagion thus represents an instance of truly affective reactions that may be mediated by visual pathways of old evolutionary origin bypassing cortical vision while still providing a cornerstone for emotion communication and affect sharing.

Health improves during economic depressions.

Having to live more lean and mean in economically hard times is apparently good for us. From Granados and Roux:
Recent events highlight the importance of examining the impact of economic downturns on population health. The Great Depression of the 1930s was the most important economic downturn in the U.S. in the twentieth century. We used historical life expectancy and mortality data to examine associations of economic growth with population health for the period 1920–1940. We conducted descriptive analyses of trends and examined associations between annual changes in health indicators and annual changes in economic activity using correlations and regression models. Population health did not decline and indeed generally improved during the 4 years of the Great Depression, 1930–1933, with mortality decreasing for almost all ages, and life expectancy increasing by several years in males, females, whites, and nonwhites. For most age groups, mortality tended to peak during years of strong economic expansion (such as 1923, 1926, 1929, and 1936–1937). In contrast, the recessions of 1921, 1930–1933, and 1938 coincided with declines in mortality and gains in life expectancy. The only exception was suicide mortality which increased during the Great Depression, but accounted for less than 2% of deaths. Correlation and regression analyses confirmed a significant negative effect of economic expansions on health gains. The evolution of population health during the years 1920–1940 confirms the counterintuitive hypothesis that, as in other historical periods and market economies, population health tends to evolve better during recessions than in expansions.

The nagging thing you don't understand about yourself

The 150th issue of the British Psychological Association's Research Digest email has posted a series of fascinating responses by leading psychologists to the request that they look inwards and share, in 150 words, one nagging thing they still don't understand about themselves.

Thursday, October 22, 2009

The ages of mankind

Here is a neat graphic from the New York Times, apparently motivated by a paper this month in The Lancet saying that half of all the babies born in developed countries in 2007 will live to be 104. This suggests the addition of a 4th life stage, "Old old age" to current categories of youth, adulthood, and old age. The graphic depicts the stages of life as viewed in different historical eras by a variety of writers.

The 'society of selves' in each of us

David Brooks does a nice layman's summary titled "Where the Wild Things Are" of our modern views on how an individual's 'character' is composed - not from the top down by a single unifying feature, but rather from a pandora's box of possible selves, each of which can appear under a particular set of circumstances.

Wednesday, October 21, 2009

The Fat and Short of It

Engber writes a brief article on the fact that not only are there correlations between excess fat and health risk, but also shorter height correlates with increased coronary heart disease, diabetes or stroke. Also,
In the labor market, the effects of height and weight tend to run in parallel. A 2004 study by John Cawley of Cornell University found that severely obese white women who weigh more than two standard deviations above average — women who weigh, for example, more than 212 pounds if they’re 5 feet 4 inches tall — are paid up to 9 percent less for their work. Likewise, a decrease in a man’s height to the 25th percentile from the 75th — roughly to 5 feet 8 inches from 6 feet— is associated with, on average, a dip in earnings of 6 to 10 percent...And like obese people, short people are less likely to finish college than those of average weight. A paper from the July issue of the journal Economics and Human Biology used survey data from more than 450,000 adults to conclude that male college graduates are, on average, more than an inch taller than men who never finished high school.

Social threat activates our body's inflammatory chemistry

This work from Dickerson et al. is both fascinating and frightening. It provides a more detailed glimpse of how social threat can transmute into self-destructive body chemistry.
This study experimentally tested whether a stressor characterized by social-evaluative threat (SET), a context in which the self can be judged negatively by others, would elicit increases in proinflammatory cytokine activity and alter the regulation of this response. This hypothesis was derived in part from research on immunological responses to social threat in nonhuman animals. Healthy female participants were assigned to perform a speech and a math task in the presence or absence of an evaluative audience (SET or non-SET, respectively). As hypothesized, stimulated production of the proinflammatory cytokine tumor necrosis factor-α (TNF-α) increased from baseline to poststressor in the SET condition, but was unchanged in the non-SET condition. Further, the increases in TNF-α production correlated with participants' cognitive appraisals of being evaluated. Additionally, the ability of glucocorticoids to shut down the inflammatory response was decreased in the SET condition. These findings underscore the importance of social evaluation as a threat capable of eliciting proinflammatory cytokine activity and altering its regulation.

Genetic influences increase between early and middle childhood.

From Davis et al.:
The generalist genes hypothesis implies that general cognitive ability (g) is an essential target for understanding how genetic polymorphisms influence the development of the human brain. Using 8,791 twin pairs from the Twins Early Development Study, we examine genetic stability and change in the etiology of g assessed by diverse measures during the critical transition from early to middle childhood. The heritability of a latent g factor in early childhood is 23%, whereas shared environment accounts for 74% of the variance. In contrast, in middle childhood, heritability of a latent g factor is 62%, and shared environment accounts for 33%. Despite increasing importance of genetic influences and declining influence of shared environment, similar genetic and shared environmental factors affect g from early to middle childhood, as indicated by a cross-age genetic correlation of .57 and a shared environmental correlation of .65. These findings set constraints on how genetic and environmental variation affects the developing brain.

Tuesday, October 20, 2009

Cognitive enhancement may come at a cost.

Johan Leher has contributed a fascinating article to Nature News (PDF here) that discusses the 30 or more strains of mice that have been genetically altered to have enhanced memory and problem solving capabilities, and more generally addresses the issue of cognitive enhancement in humans. Many of the mouse mutants have enhanced long term potentiation (LTP) at synapses (a few nerve transmissions between nerve cells enhance further transmissions). LTP is a fundamental feature of learning and memory, and it appears that by increasing its plasticity it is possible to increase cognitive capacity.

The downside of enhancing memory, at least in some unusual humans who have extraordinary memory abilities, is that they appear to be locked in details, unable to understand metaphors or generalize. Martha Farah notes that some human experiments with amphetamines show a trade-off between enhanced attention and performance on creative tasks. "The brain may have made a compromise in that having a more accurate memory interferes with the ability to generalize...You may need a little noise in order to be able to think abstractly, to get beyond the concrete and literal." A further issue is non-cognitive side effects, which have been demonstrated in mice, such as enhanced sensitivity to pain.

The Teddy Bear Effect

An interesting article from Livingston and Pearce, "The Teddy-Bear Effect: Does Having a Baby Face Benefit Black Chief Executive Officers?" The abstract:
Prior research suggests that having a baby face is negatively correlated with success among White males in high positions of leadership. However, we explored the positive role of such "babyfaceness" in the success of high-ranking Black executives. Two studies revealed that Black chief executive officers (CEOs) were significantly more baby-faced than White CEOs. Black CEOs were also judged as being warmer than White CEOs, even though ordinary Blacks were rated categorically as being less warm than ordinary Whites. In addition, baby-faced Black CEOs tended to lead more prestigious corporations and earned higher salaries than mature-faced Black CEOs; these patterns did not emerge for White CEOs. Taken together, these findings suggest that babyfaceness is a disarming mechanism that facilitates the success of Black leaders by attenuating stereotypical perceptions that Blacks are threatening. Theoretical and practical implications for research on race, gender, and leadership are discussed.

Monday, October 19, 2009

Perpetual revelations

Ross Douthat reviews a book, "The Case for God" by Karen Armstrong, that tries to land somewhere between the militant atheists and the religious fundamentalists. Armstrong makes a case for an approach to religion:
...which emphasizes the pursuit of an unknowable Deity, rather than the quest for theological correctness ... compatible with a liberal, scientific, technologically advanced society. She argues that it’s actually truer to the ancient traditions of Judaism, Islam and (especially) Christianity than is much of what currently passes for “conservative” religion. And the neglect of these traditions, she suggests, is “one of the reasons why so many Western people find the concept of God so troublesome today.”

Both modern believers and modern atheists, Armstrong contends, have come to understand religion primarily as a set of propositions to be assented to, or a catalog of specific facts about the nature of God, the world and human life. But this approach to piety would be foreign to many premodern religious thinkers, including the greatest minds of the Christian past, from the early Fathers of the Church to medieval eminences like Thomas Aquinas.

These and other thinkers, she writes, understood faith primarily as a practice, rather than as a system — not as “something that people thought but something they did.” Their God was not a being to be defined or a proposition to be tested, but an ultimate reality to be approached through myth, ritual and “apophatic” theology, which practices “a deliberate and principled reticence about God and/or the sacred” and emphasizes what we can’t know about the divine. And their religion was a set of skills, rather than a list of unalterable teachings — a “knack,” as the Taoists have it, for navigating the mysteries of human existence.

Taking it lying down...

Many cognitive neuroscience measurements are made on subjects who are supine, as for example in an MRI scanner. Given that body postures can affect behaviors (as when slumped postures lead to more 'helpless' behaviors, or erect posture with chest protruding enhances confident behavior) Harmon-Jones and Peterson compared the brain responses of subjects to anger-inducing insults while in either an upright or reclined position . It is know that left prefrontal cortex is more activated than the right prefrontal cortex during the experience of anger, particularly anger associated with approach motivational inclinations. They found, consistent with an embodied motivation prediction, that a insult delivered to subjects in an upright condition produced greater relative left lateral frontal activity than insults in a reclined condition - which produced about the same relative left lateral frontal activity as the neutral-upright condition.

Friday, October 16, 2009

Rational Irrationality

John Cassidy, in an interesting article in The New Yorker, discusses the inner logic of an economy like ours, in which behavior that is perfectly reasonable on the individual level produces calamity when aggregated in the marketplace. During both rises and falls in the markets, very small perturbations can be magnified by interlocking feedback loops that cause the economy to balloon into either a bubble or a crash.

Calvin Trillin, in a humorous but dead-on piece, has a much more simple model for the meltdown. Wall Street used to be run by the bottom third of the college class, the people who took gut general education courses (such as the Geology course referred to as "Rocks for Jocks"), and they weren't smart enough to invent all these fancy derivative investment vehicles. Then the upper third of the class that used to become teachers, doctors, or lawyers decided they needed to make more money. Mathematicians and physicists poured in to investment houses and invented all the complicated and sophisticated schemes that brought down the system.

Temperature and social proximity

An interesting bit from IJzerman and Semin, who examine the effect of warmth on social proximity:
"Holding warm feelings toward someone" and "giving someone the cold shoulder" indicate different levels of social proximity. In this article, we show effects of temperature that go beyond these metaphors people live by. In three experiments, warmer conditions, compared with colder conditions, induced (a) greater social proximity, (b) use of more concrete language, and (c) a more relational focus. Different temperature conditions were created by either handing participants warm or cold beverages (Experiment 1) or placing them in comfortable warm or cold ambient conditions (Experiments 2 and 3). These studies corroborate recent findings in the field of grounded cognition revealing that concrete experiences ground abstract concepts with which they are coexperienced. Our studies show a systemic interdependence among language, perception, and social proximity: Environmentally induced conditions shape not only language use, but also the perception and construal of social relationships.

Thursday, October 15, 2009

Texting, surfing, studying...

I've done a number of posts on the evils of multitasking (for example here and here, or enter multitasking in the search box in the left column of this blog), and thus was struck by a number of salient points in an article by Perri Klass. Here are some clips:
...A recent and much-discussed study showed decreased productivity in adults who were multitasking...you don’t really multitask, you just think you do; the brain can’t process two high-level cognitive things. What you are actually doing...is oscillating between the two...So are teenagers any better at oscillating?...It may be that multitasking is more of a problem for us old brains...parents are digital immigrants...children are digital natives...they really have come of age with these technologies.

The literature looking at media and its impact on attentional skills is just in its infancy...We don’t really know what they pay attention to, what they don’t. We don’t know how it impacts their school performance, whether it impacts their school performance.
One possibility is that performing a task while allowing distractions lengthens the amount of time that can be spent on the task, more than compensating for a decrease in efficiency.

Bright-sided

Patricia Cohen offers a review of Barbara Ehrenreich's new book “Bright-sided: How the Relentless Promotion of Positive Thinking Has Undermined America,” which takes on the happiness movement, in particular its more extreme proponents. The book, despite its title, it is not a curmudgeonly rant. Ehrenreich found in 2000 that she had breast cancer. The book chronicles:
...her stay in a world that she became intimately familiar with: the smiley-faced, pink-ribboned, positive-thinking culture that surrounds breast cancer patients...The unrelenting message was “that you had to be cheerful and accepting and that you would not recover unless you were...It’s a clever blame-the-victim sort of thing.”

Then the financial crisis hit. “Wham,” she said. “It was so clear to me that it was connected.” The relentlessly optimistic forecasts about subprime mortgages and endless increases in real estate values were the product of the positive-thinking culture. One of the fundamental tenets of the literature, Ms. Ehrenreich said, is to surround yourself with other positive thinkers and “get rid of negative people...
We’ve been weeding out anybody capable of rational thinking, of realism.”

In “Bright-sided,” she traces the roots of the nation’s blithe sunniness to a reaction against Calvinist gloom and the limits of medical science in the first half of the 19th century. Starting with Phineas Parkhurst Quimby, perhaps one of the first American New Age faith healers, she draws a line to Mary Baker Eddy, the founder of Christian Science; the psychologist William James; Ralph Waldo Emerson; Norman Vincent Peale, who published “The Power of Positive Thinking” in 1952; and the toothy television minister Joel Osteen, who preaches the gospel of prosperity...To Ms. Ehrenreich, the reliance on one’s personal disposition shifts attention from the larger social, political and economic forces behind poverty, unemployment and poor health care. “It can’t all be fixed by assertiveness training...All that shiny optimism, she said, was “like sitting in a warm bubble bath for too long.”

Wednesday, October 14, 2009

The illusion of sex

Here is a figure from a neat article (PDF here) by Richard Russell illustrating how facial contrast and cosmetics can alter the perceived sex of an androgynous face.


The Illusion of Sex. The face on the left appears male, while the face on the right appears female. Both images were produced by making slight alterations to the same original image. The eyes and lips were unaltered, and hence equally dark in both images. The remainder of the image was darkened to produce the left image, and lightened to produce the right image. The eyes and lips may appear darker in the right image than in the left image, but are notöit is an example of simultaneous contrast.

The neuropsychology of religion - neural correlates of belief

Sam Harris (the guy who wrote "The End of Faith" and "Letters to a Christian Nation"), along with a group of collaborators, has made fMRI measurements on fifteen committed Christians and fifteen nonbelievers as they evaluated the truth and falsity of religious and nonreligious propositions. Religious thinking is more associated with brain regions that govern emotion, self-representation, and cognitive conflict, while thinking about ordinary facts is more reliant upon memory retrieval networks.