Tuesday, December 08, 2015

Lower leg power predicts cognitive aging.

Gretchen Reynolds points to a study of 162 healthy female twin pairs, some identical, and some not, who 10 years previously had completed extensive examinations of their thinking and memory abilities, as well as measurements of their leg-muscle power.
...those who had had the sturdiest legs a decade ago showed the least fall-off in thinking skills, even when the scientists controlled for such factors as fatty diets, high blood pressure and shaky blood-sugar control...a muscularly powerful twin now performed about 18 percent better on memory and other cognitive tests than her weaker sister...in the brain imaging of the identical twins, if one genetically identical twin had had sturdier legs than the other at the start of the study, she now displayed significantly more brain volume and fewer “empty spaces in the brain” than her weaker sister.
Keep in mind the 'this is only one study' caution. It involved only a single analysis of the brain health of middle-aged female twins. However, it is a plausible result, because it is known that exercise causes muscles to release brain growth factors, and sturdier muscles might be expected to release more.

Monday, December 07, 2015

Racial bias and time perception.

From Moskowitz et al.:
Arousal is known to shape time perception, and heightened arousal causes one to perceive that time has slowed (i.e., a given length of time feels longer than it actually is). The current experiments illustrate that among White people who experience arousal when contemplating race (specifically those for whom appearing biased is an ongoing concern), time perception slows when they observe faces of Black men. We asked participants to judge the duration of presentation for faces of White and Black men (shown for periods ranging from 300 to 1,200 ms) relative to a standard duration of 600 ms. Evidence of bias emerged when White participants concerned with bias saw faces of Black men (e.g., durations of less than 600 ms were perceived as being greater than 600 ms). The current findings have implications for intergroup interactions in which timing is essential—for example, length of job interviews, police officers’ perception of the length of an encounter and when force should be initiated, and doctors’ perception of the length of medical encounters. Racially biased time perception is a new form of implicit bias, one exerted at the perceptual level.

Friday, December 04, 2015

Cultural specificity of human fairness.

Blake et al. do an interesting experiment on how sensitive children are to inequality. They asked one child in a pair or to accept or reject an offer of Skittles on behalf of both of them. Between ages 4 and 15 offers that were equal for both children were accepted, but older children often refected offers that would provide more Skittles to their partner. The age at which children started rejecting such offers varied across the seven countries studied (Canada, India, Mexico, Peru, Senegal, Uganda, USA) suggesting different times for development of a sense of fairness. In three countries—the United States, Canada, and Uganda—some older children also rejected offers that were unfair to their partner.
A sense of fairness plays a critical role in supporting human cooperation. Adult norms of fair resource sharing vary widely across societies, suggesting that culture shapes the acquisition of fairness behaviour during childhood. Here we examine how fairness behaviour develops in children from seven diverse societies, testing children from 4 to 15 years of age (n = 866 pairs) in a standardized resource decision task. We measured two key aspects of fairness decisions: disadvantageous inequity aversion (peer receives more than self) and advantageous inequity aversion (self receives more than a peer). We show that disadvantageous inequity aversion emerged across all populations by middle childhood. By contrast, advantageous inequity aversion was more variable, emerging in three populations and only later in development. We discuss these findings in relation to questions about the universality and cultural specificity of human fairness.

Thursday, December 03, 2015

The evolution of music from emotional signals

I want to pass on the slightly edited abstract of a recent article on the evolutionary origins of music, "Music evolution and neuroscience," in Progress in Brain Research, written by my Univ. of Wisconsin colleague Charles Snowdon.
There have been many attempts to discuss the evolutionary origins of music. We review theories of music origins and take the perspective that music is originally derived from emotional signals in both humans and animals. An evolutionary approach has two components: First, is music adaptive? How does it improve reproductive success? Second, what, if any, are the phylogenetic origins of music? Can we find evidence of music in other species? We show that music has adaptive value through emotional contagion, social cohesion, and improved well-being. We trace the roots of music through the emotional signals of other species suggesting that the emotional aspects of music have a long evolutionary history. We show how music and speech are closely interlinked with the musical aspects of speech conveying emotional information. We describe acoustic structures that communicate emotion in music and present evidence that these emotional features are widespread among humans and also function to induce emotions in animals. Similar acoustic structures are present in the emotional signals of nonhuman animals. We conclude with a discussion of music designed specifically to induce emotional states in animals, both cotton top tamarin monkeys and domestic cats.

Wednesday, December 02, 2015

Increased false-memory susceptibility after mindfulness meditation

From Wilson et al.:
The effect of mindfulness meditation on false-memory susceptibility was examined in three experiments. Because mindfulness meditation encourages judgment-free thoughts and feelings, we predicted that participants in the mindfulness condition would be especially likely to form false memories. In two experiments, participants were randomly assigned to either a mindfulness induction, in which they were instructed to focus attention on their breathing, or a mind-wandering induction, in which they were instructed to think about whatever came to mind. The overall number of words from the Deese-Roediger-McDermott paradigm that were correctly recalled did not differ between conditions. However, participants in the mindfulness condition were significantly more likely to report critical nonstudied items than participants in the control condition. In a third experiment, which tested recognition and used a reality-monitoring paradigm, participants had reduced reality-monitoring accuracy after completing the mindfulness induction. These results demonstrate a potential unintended consequence of mindfulness meditation in which memories become less reliable.

Tuesday, December 01, 2015

Religiousness decreases children’s altruistic behaviors.

Decety et al. challenge the view that religiosity facilitates prosocial behavior.:

Highlights
•Family religious identification decreases children’s altruistic behaviors
•Religiousness predicts parent-reported child sensitivity to injustices and empathy
•Children from religious households are harsher in their punitive tendencies 
Summary
Prosocial behaviors are ubiquitous across societies. They emerge early in ontogeny and are shaped by interactions between genes and culture. Over the course of middle childhood, sharing approaches equality in distribution. Since 5.8 billion humans, representing 84% of the worldwide population, identify as religious, religion is arguably one prevalent facet of culture that influences the development and expression of prosociality. While it is generally accepted that religion contours people’s moral judgments and prosocial behavior, the relation between religiosity and morality is a contentious one. Here, we assessed altruism and third-party evaluation of scenarios depicting interpersonal harm in 1,170 children aged between 5 and 12 years in six countries (Canada, China, Jordan, Turkey, USA, and South Africa), the religiousness of their household, and parent-reported child empathy and sensitivity to justice. Across all countries, parents in religious households reported that their children expressed more empathy and sensitivity for justice in everyday life than non-religious parents. However, religiousness was inversely predictive of children’s altruism and positively correlated with their punitive tendencies. Together these results reveal the similarity across countries in how religion negatively influences children’s altruism, challenging the view that religiosity facilitates prosocial behavior.

Monday, November 30, 2015

The effects of birth order on personality.

Rohrer et. al. issue a new installment on the perennial question of how our birth order influences us, with a study showing higher intelligence in firstborns,  but no birth-order effects on extraversion, emotional stability, agreeableness, conscientiousness, or imagination.:

Significance
The question of whether a person’s position among siblings has a lasting impact on that person’s life course has fascinated both the scientific community and the general public for >100 years. By combining large datasets from three national panels, we confirmed the effect that firstborns score higher on objectively measured intelligence and additionally found a similar effect on self-reported intellect. However, we found no birth-order effects on extraversion, emotional stability, agreeableness, conscientiousness, or imagination. This finding contradicts lay beliefs and prominent scientific theories alike and indicates that the development of personality is less determined by the role within the family of origin than previously thought. 
Abstract
This study examined the long-standing question of whether a person’s position among siblings has a lasting impact on that person’s life course. Empirical research on the relation between birth order and intelligence has convincingly documented that performances on psychometric intelligence tests decline slightly from firstborns to later-borns. By contrast, the search for birth-order effects on personality has not yet resulted in conclusive findings. We used data from three large national panels from the United States (n = 5,240), Great Britain (n = 4,489), and Germany (n = 10,457) to resolve this open research question. This database allowed us to identify even very small effects of birth order on personality with sufficiently high statistical power and to investigate whether effects emerge across different samples. We furthermore used two different analytical strategies by comparing siblings with different birth-order positions (i) within the same family (within-family design) and (ii) between different families (between-family design). In our analyses, we confirmed the expected birth-order effect on intelligence. We also observed a significant decline of a 10th of a SD in self-reported intellect with increasing birth-order position, and this effect persisted after controlling for objectively measured intelligence. Most important, however, we consistently found no birth-order effects on extraversion, emotional stability, agreeableness, conscientiousness, or imagination. On the basis of the high statistical power and the consistent results across samples and analytical designs, we must conclude that birth order does not have a lasting effect on broad personality traits outside of the intellectual domain.

Friday, November 27, 2015

A picture show; and, Alzheimer's and the innate immune system


Our nervous and immune systems interact with each other at the same time they both interact with our environment. Cell magazine has put together a picture show that illustrates the beauty and complexity of these interactions. It accompanies special issues of Trends in Neuroscience and Trends in Immunology that deal with neuroimmunology in disease and in normal aging. Of special interest is a description of how releasing an inhibition of the innate immune system can allow phagocytes to clear the Aβ/β-amyloid of Alzheimer's disease from the brain.

Thursday, November 26, 2015

Online political communication: more than an echo chamber?

From Barbera et al.:
We estimated ideological preferences of 3.8 million Twitter users and, using a data set of nearly 150 million tweets concerning 12 political and nonpolitical issues, explored whether online communication resembles an “echo chamber” (as a result of selective exposure and ideological segregation) or a “national conversation.” We observed that information was exchanged primarily among individuals with similar ideological preferences in the case of political issues (e.g., 2012 presidential election, 2013 government shutdown) but not many other current events (e.g., 2013 Boston Marathon bombing, 2014 Super Bowl). Discussion of the Newtown shootings in 2012 reflected a dynamic process, beginning as a national conversation before transforming into a polarized exchange. With respect to both political and nonpolitical issues, liberals were more likely than conservatives to engage in cross-ideological dissemination; this is an important asymmetry with respect to the structure of communication that is consistent with psychological theory and research bearing on ideological differences in epistemic, existential, and relational motivation. Overall, we conclude that previous work may have overestimated the degree of ideological segregation in social-media usage.

Wednesday, November 25, 2015

Choosing to be grateful.

In a piece timed for Thanksgiving, Arthur Brooks does a nice job of fetching up and giving links to references to a number of interesting studies on the positive effects of gratitude on well-being. Arthur Brooks is a person who my knee-jerk liberal reflexes would dictate be discounted immediately, because he is head of the conservative American Enterprise Institute. However this former academic is one clever dude (Here is an Op-Ed piece on abundance. Other commentaries are found here.)

Musical expertise modulates the brain’s entrainment to music.

Yet another study, by Doelling and Poeppel, showing effects of musical training on the brain and supporting a role for cortical oscillatory activity in music perception and cognition.:

Significance
We demonstrate that cortical oscillatory activity in both low (less than 8 Hz) and high (15–30 Hz) frequencies is tightly coupled to behavioral performance in musical listening, in a bidirectional manner. In light of previous work on speech, we propose a framework in which the brain exploits the temporal regularities in music to accurately parse individual notes from the sound stream using lower frequencies (entrainment) and in higher frequencies to generate temporal and content-based predictions of subsequent note events associated with predictive models.
Abstract
Recent studies establish that cortical oscillations track naturalistic speech in a remarkably faithful way. Here, we test whether such neural activity, particularly low-frequency (less than 8 Hz; delta–theta) oscillations, similarly entrain to music and whether experience modifies such a cortical phenomenon. Music of varying tempi was used to test entrainment at different rates. In three magnetoencephalography experiments, we recorded from nonmusicians, as well as musicians with varying years of experience. Recordings from nonmusicians demonstrate cortical entrainment that tracks musical stimuli over a typical range of tempi, but not at tempi below 1 note per second. Importantly, the observed entrainment correlates with performance on a concurrent pitch-related behavioral task. In contrast, the data from musicians show that entrainment is enhanced by years of musical training, at all presented tempi. This suggests a bidirectional relationship between behavior and cortical entrainment, a phenomenon that has not previously been reported. Additional analyses focus on responses in the beta range (∼15–30 Hz)—often linked to delta activity in the context of temporal predictions. Our findings provide evidence that the role of beta in temporal predictions scales to the complex hierarchical rhythms in natural music and enhances processing of musical content. This study builds on important findings on brainstem plasticity and represents a compelling demonstration that cortical neural entrainment is tightly coupled to both musical training and task performance, further supporting a role for cortical oscillatory activity in music perception and cognition.

Tuesday, November 24, 2015

Our bodies can sabotage our healthy behaviors..

I pass on an interesting chunk from Reynolds' review of work by Mansoubi et al. showing that people who use sit-to-stand workstations in their office compensate by reducing activity and increasing sitting outside of working hours, thus canceling out the effects of their virtuous exercise at the office.
...the human body and brain are funny. They often, and rather insidiously, undermine some of our best efforts to be healthier, in an attempt to maintain our physiological status quo. The result can be that we do not benefit as much as we’d hoped from changes to our lifestyles. When we slash calories to lose weight, for instance, our bodies often lower our metabolic rate, and our weight doesn’t budge much.

Similarly, studies of people who begin or greatly intensify an exercise program have shown that these exercisers often start sitting more during the hours when they are not working out, so that their overall daily energy expenditure doesn’t increase substantially and the number of hours that they spend sitting grows.

Monday, November 23, 2015

Wielding power increases testosterone in women.

Anders et al. provide evidence for a gender→testosterone pathway:

Significance
Human biology is typically studied within the framework of sex (evolved, innate factors) rather than gender (sociocultural factors), despite some attention to nature/nurture interactions. Testosterone is an exemplar of biology studied as natural difference: men’s higher testosterone is typically seen as an innate “sex” difference. However, our experiment demonstrates that gender-related social factors also matter, even for biological measures. Gender socialization may affect testosterone by encouraging men but not women toward behaviors that increase testosterone. This shows that research on human sex biology needs to account for gender socialization and that nurture, as well as nature, is salient to hormone physiology. Our paper provides a demonstration of a novel gender→testosterone pathway, opening up new avenues for studying gender biology.
Abstract
Testosterone is typically understood to contribute to maleness and masculinity, although it also responds to behaviors such as competition. Competition is crucial to evolution and may increase testosterone but also is selectively discouraged for women and encouraged for men via gender norms. We conducted an experiment to test how gender norms might modulate testosterone as mediated by two possible gender→testosterone pathways. Using a novel experimental design, participants (trained actors) performed a specific type of competition (wielding power) in stereotypically masculine vs. feminine ways. We hypothesized in H1 (stereotyped behavior) that wielding power increases testosterone regardless of how it is performed, vs. H2 (stereotyped performance), that wielding power performed in masculine but not feminine ways increases testosterone. We found that wielding power increased testosterone in women compared with a control, regardless of whether it was performed in gender-stereotyped masculine or feminine ways. Results supported H1 over H2: stereotyped behavior but not performance modulated testosterone. These results also supported theory that competition modulates testosterone over masculinity. Our findings thus support a gender→testosterone pathway mediated by competitive behavior. Accordingly, cultural pushes for men to wield power and women to avoid doing so may partially explain, in addition to heritable factors, why testosterone levels tend to be higher in men than in women: A lifetime of gender socialization could contribute to “sex differences” in testosterone. Our experiment opens up new questions of gender→testosterone pathways, highlighting the potential of examining nature/nurture interactions and effects of socialization on human biology.

Friday, November 20, 2015

Flip-Flops in medical advice.

I want to forward readers some clips I've taken from a review by Zuger of a recent book "Ending Medical Reversal" by Prasad and Cifu. After glancing through the following you might want to also have a look a this article by Span on the over-treatment of older patients.
Prasad and Cifu... have set themselves the task of figuring out how often modern medicine reverses itself, analyzing why it happens, and suggesting ways to make it stop...[they] extrapolate from past reversals to conclude that about 40 percent of what we consider state-of-the-art health care is likely to turn out to be unhelpful or actually harmful.
Recent official flip-flops include habits of treating everything from lead poisoning to blood clots, from kidney stones to heart attacks. One reversal concerned an extremely common orthopedic procedure, the surgical repair of the meniscus in the knee, which turns out to be no more effective than physical therapy alone. The interested reader can plow through almost 150 disproved treatments in the book’s appendix.
What could make more sense, after all, than finding some cancers early, fixing a piece of torn cartilage, closing a hole in the heart, and propping open blood vessels that have become perilously narrow? And yet not one of these helpful interventions has been shown to make a difference in the health or survival of patients who obediently line up to have them done.
“Often the study of the study of how therapies should work is much more extensive and comes before the study of whether therapies do work,” the authors write. Thus a medical culture based on “should work” rather than “does work” is condemned to constantly correct itself when the science is finally evaluated for outcomes that matter.
To fix this constant backtracking would require nothing less than a revolution in how doctors are trained, with an emphasis on the proven and practical rather than the theoretical. (It would also require a second revolution in how doctors practice, with less prestige and remuneration for coming up with new ideas and more for validating old ones.)

Thursday, November 19, 2015

Divided we fall - putting social progress on par with prosperity

Laura Levis, in Harvard Magazine, describes work of Porter and Stern, who have developed a social progress index that:
...ranks 133 countries on multiple dimensions of social and environmental performance in three main categories: Basic Human Needs (food, water, shelter, safety); Foundations of Wellbeing (basic education, information, health, and a sustainable environment); and Opportunity (freedom of choice, freedom from discrimination, and access to higher education). Porter considers the index “the most comprehensive framework developed for measuring social progress, and the first to measure social progress independently of gross domestic product (GDP)."

The United States may rank sixth among countries in terms of GDP per capita, but its results on the Social Progress Index are lackluster. It is sixteenth overall in social progress: well below Canada, the United Kingdom, Germany, and Japan in several key areas, including citizens’ quality of life and provision of basic human needs. The nation ranks thirtieth in personal safety, forty-fifth in access to basic knowledge, sixty-eighth on health and wellness, and seventy-fourth in ecosystem sustainability. “We had a lot of firsts in social progress over the years in America,” Porter points out, “but we kind of lost our rhythm and our momentum.”
About 20 or 30 years ago, for reasons Porter says he cannot completely explain, the rate of progress in America began to slow down. As a society, he points out, Americans slowly became more divided, and important priorities such as healthcare, education, and politics suffered. “We had gridlock, whether it’s unions or whether it’s ideological differences, and—although we’ve made some big steps in certain areas of human rights like gay rights—if you think about the really core things like our education system and our health system, we’re just not moving,” he says. “I think our political system isn’t helping, because we’re all about political gains and blocking the other guy, rather than compromising and getting things done.”

Wednesday, November 18, 2015

A personal note, the Steinway B now in Fort Lauderdale - some Chopin

After a few tense moments,  my Steinway B is now moved from Wisconsin to Florida.


I've upgraded my video and audio recording equipment, finally got the bugs out of the process, and thought I would pass on my first test recording - of a Chopin Nocturne that I plan to play at a recital next February here in Fort Lauderdale.  The vers. 3 refers to the fact that this is the third recording of this piece that I have put on my YouTube channel.

 

Neuropolitics - reading the electorate's mind.

Members of our two major political parties increasingly seem to inhabit alternative realities that are utterly incomprehending of each other. How about reinforcing these bubbles with technology for feeding blocks of voters only what they want to hear? A NYTimes piece by Kevin Randall describes some really spooky new political tools: digital campaign signs that note the facial and emotional reactions of those watching their message and tally emotional reactions like happiness, surprise, anger, disgust, fear and sadness. This permits alteration of the message to elicit desired responses. Such devices have been used in Mexico, Poland, Turkey, and probably the U.S.
In Mexico, President Enrique Peña Nieto’s campaign and his party, the Institutional Revolutionary Party, or PRI, employed tools to measure voters’ brain waves, skin arousal, heart rates and facial expressions during the 2012 presidential campaign. More recently, the party has been using facial coding to help pick its best candidates, one consultant says. Some officials even speak openly about their embrace of neuropolitical techniques, and not just for campaigning, but for governing as well.
Neuromarketing consultants say they are conducting research like this in more than a dozen countries, including Argentina, Brazil, Costa Rica, El Salvador, Russia, Spain and, to a much lesser extent, the United States.
One neuromarketing firm says it has worked for a Hillary Rodham Clinton presidential campaign committee to help it improve its targeting and messages.
David Plouffe, President Obama’s former campaign manager, said the tools “would be new ground for political campaigns...The richness of this data compared to what is gathered today in testing ads or evaluating speeches and debates, which is the trusty old dial test and primitive qualitative methods, is hard to comprehend. It gets more to emotion, intensity and a more complex understanding of how people are reacting.”
Added note: Mexico's governing party, the PRI, has now said it will no longer employ the techniques described above.