The evolution of dance

From Laland et al.:

Evidence from multiple sources reveals a surprising link between imitation and dance. As in the classical correspondence problem central to imitation research, dance requires mapping across sensory modalities and the integration of visual and auditory inputs with motor outputs. Recent research in comparative psychology supports this association, in that entrainment to a musical beat is almost exclusively observed in animals capable of vocal or motor imitation. Dance has representational properties that rely on the dancers’ ability to imitate particular people, animals or events, as well as the audience’s ability to recognize these correspondences. Imitation also plays a central role in learning to dance and the acquisition of the long sequences of choreographed movements are dependent on social learning. These and other lines of evidence suggest that dancing may only be possible for humans because its performance exploits existing neural circuitry employed in imitation.

This painting by Edgar Degas not only depicts a ballet rehearsal but also illustrates the roles of imitation and synchrony

Clips from the body of the article, with another figure:

...there can be no doubt that, compared to other animals, humans are exceptional imitators. It may be no coincidence that a recent PET scan analysis of the neural basis of dance found that foot movement to music excited regions of neural circuitry (e.g. the right frontal operculum) previously associated with imitation. Dancing may only be possible because its performance exploits the neural circuitry employed in imitation. Such reasoning applies equally where individuals dance alone; unlike much human behavior, dancing inherently seems to require a brain capable of solving the correspondence problem.

Dance often tells a story, and this representational quality provides another link with imitation. For instance, in the astronomical dances of ancient Egypt, priests and priestesses, accompanied by harps and pipes, mimed significant events in the story of a god or imitated cosmic patterns, such as the rhythm of night and day. Africa, Asia, Australasia and Europe all possess long-standing traditions for masked dances, in which the performers portray the character associated with the mask and enact religious stories. Native Americans have many animal dances, such as the Buffalo dance, which was thought to lure buffalo herds close to the village, and the eagle dance, which is a tribute to these revered birds. This tradition continues to the present. In 2009, Rambert (formerly the Rambert Dance Company), a world leader in contemporary dance, marked the bicentenary of Charles Darwin’s birth and 150th anniversary of his seminal work On the Origin of Species by collaborating with one of us (N.C.) to produce Comedy of Change (Figure above), which evoked animal behaviour on stage with spellbinding accuracy. In all such instances, the creation and performance of the dance requires an ability on the part of the dancer to imitate the movements and sounds of particular people, animals, or events. Such dances re-introduce the correspondence problem, as the dancer, choreographer and audience must be able to connect the dancers’ movements to the target phenomenon they represent.

On teaching old dogs new tricks.

Metcalfe et al. find that older healthy adults not only are better than young adults at answering general-information questions in the first place, but also, when they do make a mistake, they are more likely than young adults to correct those errors. Correcting errors is, of course, the quintessential new-learning task: To correct mistakes, one needs to supplant entrenched responses with new ones. The fact that older adults display greater facility at error correction than young adults contravenes the view that aging necessarily produces cognitive rigidity and an inability to learn. Here is their abstract:

Although older adults rarely outperform young adults on learning tasks, in the study reported here they surpassed their younger counterparts not only by answering more semantic-memory general-information questions correctly, but also by better correcting their mistakes. While both young and older adults exhibited a hypercorrection effect, correcting their high-confidence errors more than their low-confidence errors, the effect was larger for young adults. Whereas older adults corrected high-confidence errors to the same extent as did young adults, they outdid the young in also correcting their low-confidence errors. Their event-related potentials point to an attentional explanation: Both groups showed a strong attention-related P3a in conjunction with high-confidence-error feedback, but the older adults also showed strong P3as to low-confidence-error feedback. Indeed, the older adults were able to rally their attentional resources to learn the true answers regardless of their original confidence in the errors and regardless of their familiarity with the answers.

Several perspectives on the valuation of outgroups.

A recent issue of the Proceedings of the National Academy of Science has two relevant articles:

Keelah et al. show that Americans’ stereotypes about racial groups may actually reflect their stereotypes about these groups’ presumed home ecologies. Harsh and unpredictable (“desperate”) ecologies induce fast strategy behaviors such as impulsivity, whereas resource-sufficient and predictable (“hopeful”) ecologies induce slow strategy behaviors such as future focus.

...when provided with information about a person’s race (but not ecology), individuals’ inferences about blacks track stereotypes of people from desperate ecologies, and individuals’ inferences about whites track stereotypes of people from hopeful ecologies. However, when provided with information about both the race and ecology of others, individuals’ inferences reflect the targets’ ecology rather than their race: black and white targets from desperate ecologies are stereotyped as equally fast life history strategists, whereas black and white targets from hopeful ecologies are stereotyped as equally slow life history strategists. These findings suggest that the content of several predominant race stereotypes may not reflect race, per se, but rather inferences about how one’s ecology influences behavior.

And, Ginges et al. show that thinking from God's perspective decreases biased valuation of the life of a nonbeliever.

Religious belief is often thought to motivate violence because it is said to promote norms that encourage tribalism and the devaluing of the lives of nonbelievers. If true, this should be visible in the multigenerational violent conflict between Palestinians and Israelis which is marked by a religious divide. We conducted experiments with a representative sample of Muslim Palestinian youth (n = 555), examining whether thinking from the perspective of Allah (God), who is the ultimate arbitrator of religious belief, changes the relative value of Jewish Israelis’ lives (compared with Palestinian lives). Participants were presented with variants of the classic “trolley dilemma,” in the form of stories where a man can be killed to save the lives of five children who were either Jewish Israeli or Palestinian. They responded from their own perspective and from the perspective of Allah. We find that whereas a large proportion of participants were more likely to endorse saving Palestinian children than saving Jewish Israeli children, this proportion decreased when thinking from the perspective of Allah. This finding raises the possibility that beliefs about God can mitigate bias against other groups and reduce barriers to peace.

Also, in the journal Psychological Science, Roets et al. consider the case of Singapore, which contradicts:

...numerous empirical studies that have consistently demonstrated the seemingly inextricable link between authoritarianism and negative attitudes about out-groups. Indeed, in the authoritarian mind, minorities are readily perceived as “bad, disruptive, immoral, and deviant” people who do not fit into society... However, what if authoritarians live in a society in which a very strong and established authority most explicitly endorses diversity and multiculturalism, thereby enforcing a social norm that is in direct opposition to authoritarians’ “natural” negative attitudes toward minorities? Over the past 50 years, the Singaporean government (run by the People’s Action Party) has been highly committed to regulating its ethnically diverse society and promoting multiculturalism through a variety of ingenious yet most consequential measures. A prime example is the imposition of strict ethnic quotas in public residential estates

They analyzed data from a questionnaire measuring authoritarianism that was completed by 249 Singaporean students (the target sample; and 245 Belgian students (the comparison group)...the Belgian control group showed the usual negative relationships between authoritarianism and multiculturalism and between authoritarianism and positive attitudes about out-groups, as found in all previous research. In the Singaporean sample, however, there were significant, positive relationships between authoritarianism and multiculturalism and between authoritarianism and positive attitudes about out-groups... [The] results demonstrate that when a strong authority explicitly and relentlessly endorses diversity and multiculturalism, such a perspective can be adopted even (and especially) by people who are intuitively most opposed to diversity.

You might also note the comments of Aaron Wendland on the writings of Emmanuel Levinas, after World War II, on deep-seated and often irrational fear of the “other.”

Levinas’s antihistamine for our allergic reactions involves three things: an appeal to the “infinity” in human beings, a detailed description of face-to-face encounters and an account of a basic hospitality that constitutes humanity.

Paying attention to your body can increase resilience to stress

Resilience is the ability to rapidly return to normal, both physically and emotionally, after a stressful event. Reynolds points to work by Haase et al., who provide fMRI evidence that in high resilience individuals brain areas receiving signals from the body become more active during stress and supress signals to brain areas that intensify body arousal. Individuals with lower resilience show reduced attention to bodily signals but greater neural processing to aversive bodily perturbations. Here's the Haase et al. abstract:

Highlights

• Low resilience individuals are less sensitive to body-relevant information. • Low resilience individuals show an exaggerated brain response to an aversive interoceptive stimulus. • This mismatch between attention to and processing of interoceptive afferents may result in poor adaptation in stressful situations.

Abstract

This study examined neural processes of resilience during aversive interoceptive processing. Forty-six individuals were divided into three groups of resilience Low (LowRes), high (HighRes), and normal (NormRes), based on the Connor-Davidson Resilience Scale (2003). Participants then completed a task involving anticipation and experience of loaded breathing during functional magnetic resonance imaging (fMRI) recording. Compared to HighRes and NormRes groups, LowRes self-reported lower levels of interoceptive awareness and demonstrated higher insular and thalamic activation across anticipation and breathing load conditions. Thus, individuals with lower resilience show reduced attention to bodily signals but greater neural processing to aversive bodily perturbations. In low resilient individuals, this mismatch between attention to and processing of interoceptive afferents may result in poor adaptation in stressful situations.

Biochemical individuality obsoletes many dietary recommendations and the glycemic index.

An important paper by a Weizmann Institute group has been languishing in my list of potential posts, and Murphy's summary of their work now prods me to pass on their bottom line: the glycemic index, used to rank foods according to their effects on blood sugar, is not really useful, because people differ strikingly in their indivual biochemistries, the way in which they extract energy from different foods. The Weizmann group devised "a machine-learning algorithm that integrates blood parameters, dietary habits, anthropometrics, physical activity, and gut microbiota measured...and showed that it accurately predicts personalized postprandial glycemic response to real-life meals." Companies like Nutrigenomix have begun to offer personalized nutrition assessment based on individual genomics. Here is the Weizmann Inst. info:

Highlights

•High interpersonal variability in post-meal glucose observed in an 800-person cohort 

•Using personal and microbiome features enables accurate glucose response prediction 

•Prediction is accurate and superior to common practice in an independent cohort 

•Short-term personalized dietary interventions successfully lower post-meal glucose

Summary

Elevated postprandial blood glucose levels constitute a global epidemic and a major risk factor for prediabetes and type II diabetes, but existing dietary methods for controlling them have limited efficacy. Here, we continuously monitored week-long glucose levels in an 800-person cohort, measured responses to 46,898 meals, and found high variability in the response to identical meals, suggesting that universal dietary recommendations may have limited utility. We devised a machine-learning algorithm that integrates blood parameters, dietary habits, anthropometrics, physical activity, and gut microbiota measured in this cohort and showed that it accurately predicts personalized postprandial glycemic response to real-life meals. We validated these predictions in an independent 100-person cohort. Finally, a blinded randomized controlled dietary intervention based on this algorithm resulted in significantly lower postprandial responses and consistent alterations to gut microbiota configuration. Together, our results suggest that personalized diets may successfully modify elevated postprandial blood glucose and its metabolic consequences.

Posthumanism - the quantification craze and the death of beauty

An eloquent recent essay, “Among the Disrupted” by Leon Wieseltier (pointed to by a Brooks Op-Ed piece), is worth your attention. It opens with a screed on the how journalism has degenerated into a “twittering cacophony of one-liners and promotional announcements” with its force of expression diminishing as its frequency grows, and how culture is being degraded by “the idolatry of metrics and quantification applied to things that cannot be captured by numbers.“ Below are a few clips... Here is a core sentiment:

The notion that the nonmaterial dimensions of life must be explained in terms of the material dimensions, and that nonscientific understandings must be translated into scientific understandings if they are to qualify as knowledge, is increasingly popular inside and outside the university, where the humanities are disparaged as soft and impractical and insufficiently new. The contrary insistence that the glories of art and thought are not evolutionary adaptations, or that the mind is not the brain, or that love is not just biology’s bait for sex, now amounts to a kind of heresy. So, too, does the view that the strongest defense of the humanities lies not in the appeal to their utility — that literature majors may find good jobs, that theaters may economically revitalize neighborhoods — but rather in the appeal to their defiantly nonutilitarian character, so that individuals can know more than how things work, and develop their powers of discernment and judgment, their competence in matters of truth and goodness and beauty, to equip themselves adequately for the choices and the crucibles of private and public life.

Actually, I think the sentiments in the above paragraph are misguided (is Wieseltier really a classical vitalist?), but that's possible grist for another post. Continuing....

...the worldview that is ascendant may be described as posthumanism.

…what is humanism?…The most common understanding of humanism is that it denotes a pedagogy and a worldview. ..The worldview takes many forms: a philosophical claim about the centrality of humankind to the universe, and about the irreducibility of the human difference to any aspect of our animality; a methodological claim about the most illuminating way to explain history and human affairs, and about the essential inability of the natural sciences to offer a satisfactory explanation; a moral claim about the priority, and the universal nature, of certain values, not least tolerance and compassion.

Here is a humanist proposition for the age of Google: The processing of information is not the highest aim to which the human spirit can aspire, and neither is competitiveness in a global economy. The character of our society cannot be determined by engineers.

…machines may be more neutral about their uses than the propagandists and the advertisers want us to believe. We can leave aside the ideology of digitality and its aggressions, and regard the devices as simply new means for old ends. Tradition “travels” in many ways. It has already flourished in many technologies — but only when its flourishing has been the objective. I will give an example from the humanities. The day is approaching when the dream of the democratization of knowledge — Borges’s fantasy of “the total library” — will be realized. Soon all the collections in all the libraries and all the archives in the world will be available to everyone with a screen. Who would not welcome such a vast enfranchisement? But universal accessibility is not the end of the story, it is the beginning. The humanistic methods that were practiced before digitalization will be even more urgent after digitalization, because we will need help in navigating the unprecedented welter. Searches for keywords will not provide contexts for keywords. Patterns that are revealed by searches will not identify their own causes and reasons. The new order will not relieve us of the old burdens, and the old pleasures, of erudition and interpretation.

The persistence of humanism through the centuries, in the face of formidable intellectual and social obstacles, has been owed to the truth of its representations of our complexly beating hearts, and to the guidance that it has offered, in its variegated and conflicting versions, for a soulful and sensitive existence…In a society rife with theories and practices that flatten and shrink and chill the human subject, the humanist is the dissenter. Never mind the platforms. Our solemn responsibility is for the substance.

Homosexuality as a discrete class.

Norris et al. contribute to previous work engaging the question of whether homosexuality has a taxonic structure of categories of individuals with distinct orientation, or whether sexual orientation lies on the sort of continuum suggested by Kinsey and others. Because individuals who report nonheterosexual identities, behavior, and attractions are more likely than heterosexual individuals to meet criteria for a psychiatric disorder their study utilized a National Epidemiologic Survey on Alcohol and Related Conditions. The survey was conducted through personal interviews with one randomly selected adult in each household. Their abstract:

Previous research on the latent structure of sexual orientation has returned conflicting results, with some studies finding a dimensional structure (i.e., ranging quantitatively along a spectrum) and others a taxonic structure (i.e., categories of individuals with distinct orientations). The current study used a sample (N = 33,525) from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC). A series of taxometric analyses were conducted using three indicators of sexual orientation: identity, behavior, and attraction. These analyses, performed separately for women and men, revealed low-base-rate same-sex-oriented taxa for men (base rate = 3.0% of those sampled) and women (base rate = 2.7%). Generally, taxon membership conferred an increased risk for psychiatric and substance-use disorders. Although taxa were present for men and women, women demonstrated greater sexual fluidity, such that any level of same-sex sexuality conferred taxon membership for men but not for women.

Another installment on anti-aging chemistry - pterostilbene

I thought I would report on my recent meandering into recent work on the putative anti-aging compounds Resveratrol and Pterostilbene, which are found in some fruits, nuts, and vegetables. (I reported my experience with resveratrol in a 2008 MindBlog post.) The meandering started with a glance at Weintraub's piece on health benefits of red wine versus grape juice. She quoted M.I.T. anti-aging researcher Leonard Guarente, who started the company Elysium, which sells Pterostilbene, a resveratrol cousin that is more easily absorbed after oral ingestion:

Poulose et al. have recently reviewed articles on the effects of pterostilbene and resveratrol on brain health and chemistry (motivated readers can obtain a PDF from me, see also the article by Mitteldorf and the website examine.com).

Even after the neutral to negative experience with resveratrol that I reported in the MindBlog post mentioned above, I've just ordered a bit of pterostilbene to see if I experience some of the cognitive effects claimed.  I'll report on the experience.

How to be bad together - Punishing pro-social behavior.

I pass on part of a brief essay by Gloria Origgi noting the work of Gächter and Herrmann, who examined positive and negative reciprocity in different groups selected within Switzerland and Russia.:

There is a vast literature showing how direct and indirect reciprocity are important tools for dealing with human cooperation. Many experiments have shown that people use “altruistic punishment” to sustain cooperation, that is, they are willingly to pay without receiving anything back just in order to sanction those who don’t cooperate, and hence promote pro-social behavior.

Yet, Gächter and Herrmann showed in their surprising paper that in some cultures, when people were tested in cooperative games (such as the “public good game”), the people who cooperated were punished, rather than the free-riders.

In some societies, people prefer to act anti-socially and they take actions to make sure that the others do the same! This means that cooperation in societies is not always for the good: you can find cartels of anti-social people who don’t care at all for the common good and prefer to cooperate for keeping a status quo that suits them even if the collective outcome is a mediocre result.

As an Italian with first-hand experience in living in a country where, if you behave well, you are socially and legally sanctioned, this news was exciting, even inspiring … perhaps cooperation is not an inherent virtue of the human species. Perhaps, in many circumstances, we prefer to stay with those who share our selfishness and weaknesses and to avoid pro-social altruistic individuals. Perhaps it's not abnormal to live outside a circle of empathy.

So what’s the scientific “news that stays news”: Cooperation for the collective worse is as widespread as cooperation for a better society!

Purity, Disgust and Donald Trump

Following the thread of the past few posts (on the partisan divide and empathy), I want to pass on this must-read article by Thomas Edsall, who summarizes work of academic researchers probing the role of purity/disgust, order/chaos, anger and fear, in the electorate. Here is a great graphic from the article:

Our strongest prejudice - partisan hostility

Jonathan Haidt points to the fascinating work by political scientists Shanto Iyengar and Sean Westwood, titled “Fear and Loathing Across Party Lines: New Evidence on Group Polarization.”, who found - in four studies designed to reveal prejudice based on race, gender, religion, or political party or ideology - that cross-partisan prejudice was the largest. For white participants who identified with a party, the cross-partisan effect was about 50 percent larger than the cross-race effect. Haidt points out that This is extremely bad news for America because:

...rising cross-partisan hostility means that Americans increasingly see the other side not just as wrong but as evil, as a threat to the very existence of the nation, according to Pew Research. Americans can expect rising polarization, nastiness, paralysis, and governmental dysfunction for a long time to come...This is extremely bad news for science and universities because universities are usually associated with the left...we can expect increasing hostility from Republican legislators toward universities and the things they desire, including research funding and freedom from federal and state control...This is a warning for the rest of the world because some of the trends that have driven America to this point are occurring in many other countries, including: rising education and individualism (which make people more ideological), rising immigration and ethnic diversity (which reduces social capital and trust), and stagnant economic growth (which puts people into a zero-sum mindset).

The situation is made worse by the "motive attribution asymmetry" that I have referenced in a previous post. Both sides of a political divide attribute their own aggressive behavior to love, but the opposite side's to hatred. Millions of Americans believe that their side is basically benevolent while the other side is evil and out to get them.

How learning shapes the empathic brain.

From Hein et al.:

Abstract

Deficits in empathy enhance conflicts and human suffering. Thus, it is crucial to understand how empathy can be learned and how learning experiences shape empathy-related processes in the human brain. As a model of empathy deficits, we used the well-established suppression of empathy-related brain responses for the suffering of out-groups and tested whether and how out-group empathy is boosted by a learning intervention. During this intervention, participants received costly help equally often from an out-group member (experimental group) or an in-group member (control group). We show that receiving help from an out-group member elicits a classical learning signal (prediction error) in the anterior insular cortex. This signal in turn predicts a subsequent increase of empathy for a different out-group member (generalization). The enhancement of empathy-related insula responses by the neural prediction error signal was mediated by an establishment of positive emotions toward the out-group member. Finally, we show that surprisingly few positive learning experiences are sufficient to increase empathy. Our results specify the neural and psychological mechanisms through which learning interacts with empathy, and thus provide a neurobiological account for the plasticity of empathic reactions.

Virtual reality going mainstream will enhance our understanding of consciousness.

These clips from Thomas Metzinger are fascinating:

2016 will be the year in which VR finally breaks through at the mass consumer level. What is more, users will soon be enabled to toggle between virtual, augmented, and substitutional reality, experiencing virtual elements intermixed with their “actual” physical environment or an omnidirectional video feed giving them the illusion of being in a different location in space and/or time, while insight may not always be preserved. Oculus Rift, Zeiss VR One, Sony PlayStation VR, HTC Vive, Samsung’s Galaxy Gear VR or Microsoft’s HoloLens are just the very beginning...

The real news, however, may be that the general public will gradually acquire a new and intuitive understanding of what their very own conscious experience really is and what it always has been. VR is the representation of possible worlds and possible selves, with the aim of making them appear as real as possible—ideally, by creating a subjective sense of “presence” in the user. Interestingly, some of our best theories of the human mind and conscious experience describe it in a very similar way: Leading theoretical neurobiologists like Karl Friston and eminent philosophers like Jakob Hohwy and Andy Clark describe it as the constant creation of internal models of the world, virtual neural representations of reality which express probability density functions and work by continuously generating hypotheses about the hidden causes of sensory input, minimizing their prediction error. In 1995, Finnish philosopher Antti Revonsuo already pointed out how conscious experience exactly is a virtual model of the world, a dynamic internal simulation, which in standard situations cannot be experienced as a virtual model because it is phenomenally transparent—we “look through it” as if we were in direct and immediate contact with reality. What is historically new, and what creates not only novel psychological risks but also entirely new ethical and legal dimensions, is that one virtual reality gets ever more deeply embedded into another virtual reality: The conscious mind of human beings, which has evolved under very specific conditions and over millions of years, now gets causally coupled and informationally woven into technical systems for representing possible realities. Increasingly, consciousness is not only culturally and socially embedded, but also shaped by a specific technological niche that, over time, quickly acquires rapid, autonomous dynamics and ever new properties. This creates a complex convolution, a nested form of information flow in which the biological mind and its technological niche influence each other in ways we are just beginning to understand.

How our brains change during the day.

I am reminded what a rigid daily schedule my body keeps and expects every time I vary my routine slightly (changing a meal time, exercise, happy hour, bedtime)...my body doesn't like it, feels off kilter. Travel of the sort I've been doing over the past month is a huge disrupter. I'm also clear that any demanding and analytical thinking I might want to do should happen before noontime, because by 4 p.m. (a low blood sugar time for the body), my mind has become very lazy.

McClung and collaborators have done the fascinating experiment of looking at gene expression during the day in brain areas important in learning, memory, and emotion, in 146 young and old brains, finding differences on aging. The brains were from subjects who had died suddenly, as in a car accident. They built on the work of Akil and collaborators who earlier had shown the activity of ~1000 genes varies in a daily pattern that allows the time of death to be predicted within an hour. That pattern was disrupted in people with major depressive disorders. From McClung's group:  

Significance

Circadian rhythms are important in nearly all processes in the brain. Changes in rhythms that come with aging are associated with sleep problems, problems with cognition, and nighttime agitation in elderly people. In this manuscript, we identified transcripts genome-wide that have a circadian rhythm in expression in human prefrontal cortex. Moreover, we describe how these rhythms are changed during normal human aging. Interestingly, we also identified a set of previously unidentified transcripts that become rhythmic only in older individuals. This may represent a compensatory clock that becomes active with the loss of canonical clock function. These studies can help us to develop therapies in the future for older people who suffer from cognitive problems associated with a loss of normal rhythmicity.

Abstract

With aging, significant changes in circadian rhythms occur, including a shift in phase toward a “morning” chronotype and a loss of rhythmicity in circulating hormones. However, the effects of aging on molecular rhythms in the human brain have remained elusive. Here, we used a previously described time-of-death analysis to identify transcripts throughout the genome that have a significant circadian rhythm in expression in the human prefrontal cortex [Brodmann’s area 11 (BA11) and BA47]. Expression levels were determined by microarray analysis in 146 individuals. Rhythmicity in expression was found in ∼10% of detected transcripts (P less than 0.05). Using a metaanalysis across the two brain areas, we identified a core set of 235 genes (q less than 0.05) with significant circadian rhythms of expression. These 235 genes showed 92% concordance in the phase of expression between the two areas. In addition to the canonical core circadian genes, a number of other genes were found to exhibit rhythmic expression in the brain. Notably, we identified more than 1,000 genes (1,186 in BA11; 1,591 in BA47) that exhibited age-dependent rhythmicity or alterations in rhythmicity patterns with aging. Interestingly, a set of transcripts gained rhythmicity in older individuals, which may represent a compensatory mechanism due to a loss of canonical clock function. Thus, we confirm that rhythmic gene expression can be reliably measured in human brain and identified for the first time (to our knowledge) significant changes in molecular rhythms with aging that may contribute to altered cognition, sleep, and mood in later life.

Nature's warning system.

A colleague in my Chaos and Complexity discussion group at the Univ. of Wisconsin passed on this Atlantic article in which my Zoology colleague Steve Carpenter is extensively quoted, which is well worth reading. Complex systems, like ecological food webs, the brain, and the climate, give off characteristic signals when a disastrous transformation is around the corner.

Higher inequality correlates with less generous rich people.

From Côté et. al.:

Research on social class and generosity suggests that higher-income individuals are less generous than poorer individuals. We propose that this pattern emerges only under conditions of high economic inequality, contexts that can foster a sense of entitlement among higher-income individuals that, in turn, reduces their generosity. Analyzing results of a unique nationally representative survey that included a real-stakes giving opportunity (n = 1,498), we found that in the most unequal US states, higher-income respondents were less generous than lower-income respondents. In the least unequal states, however, higher-income individuals were more generous. To better establish causality, we next conducted an experiment (n = 704) in which apparent levels of economic inequality in participants’ home states were portrayed as either relatively high or low. Participants were then presented with a giving opportunity. Higher-income participants were less generous than lower-income participants when inequality was portrayed as relatively high, but there was no association between income and generosity when inequality was portrayed as relatively low. This research finds that the tendency for higher-income individuals to be less generous pertains only when inequality is high, challenging the view that higher-income individuals are necessarily more selfish, and suggesting a previously undocumented way in which inequitable resource distributions undermine collective welfare... Our findings offer a more complete understanding of the association between income and generosity and have implications for contemporary debates about the social impact of unequal resource distributions.

A positive tonic: Human Progress Quantified

Edge.org has just posted responses to its 2016 question of the year "What do you consider the most interesting recent [scientific] news? What makes it important?" Over the next period of time I'm going to be posting edited clips from some of these responses, starting today with Steven Pinker's contribution on human progress:

Human intuition is a notoriously poor guide to reality...Fortunately, as the bugs in human cognition have become common knowledge, the workaround—objective data—has become more prevalent...Sports have been revolutionized by Moneyball, policy by Nudge, punditry by 538.com, forecasting by tournaments and prediction markets, philanthropy by effective altruism, the healing arts by evidence-based medicine.

The most interesting news is that the quantification of life has been extended to the biggest question of all: Have we made progress... in improving the human condition?...Most people agree that life is better than death, health better than disease, prosperity better than poverty, knowledge better than ignorance, peace better than war, safety better than violence, freedom better than coercion. That gives us a set of yardsticks by which we can measure whether progress has actually occurred. The interesting news is that the answer is mostly "yes."... the rate of homicides and war deaths had plummeted over time...People are living longer and healthier lives, not just in the developed world but globally. A dozen infectious and parasitic diseases are extinct or moribund. Vastly more children are going to school and learning to read. Extreme poverty has fallen worldwide from 85 to 10 percent. Despite local setbacks, the world is more democratic than ever. Women are better educated, marrying later, earning more, and in more positions of power and influence. Racial prejudice and hate crimes have decreased since data were first recorded. The world is even getting smarter: In every country, IQ has been increasing by three points a decade.

"Ecomodernists" such as Stewart Brand, Jesse Ausubel, and Ruth DeFries have shown that many indicators of environmental health have improved over the last half-century, and that there are long-term historical processes, such as the decarbonization of energy, the dematerialization of consumption, and the minimization of farmland that can be further encouraged...for all the ways in which the world today falls short of utopia, the norms and institutions of modernity have put us on a good track. We should work on improving them further, rather than burning them down in the conviction that nothing could be worse than our current decadence and in the vague hope that something better might rise from their ashes...quantified human progress emboldens us to seek more of it...The empowering feature of a graph is that it invites one to identify the forces that are pushing a curve up or down, and then to apply them to push it further in the same direction.

Boosting our brain plasticity.

Wow, this study by Forsyth et al. makes me want to run out and buy a bottle of D-cycloserine, which they show enhances experience-dependent learning, i.e. brain plasticity, in healthy adult humans. (Actually, it's expensive, and experimenting with it by yourself is not a good idea.)

 Significance

Experience-dependent plasticity is the capacity of the brain to undergo changes following environmental input and use, and is a primary means through which the adult brain enables new behavior. In the current study, we provide evidence that enhancing signaling at the glutamate N-methyl-D-aspartate receptor (NMDAR) can enhance the mechanism underlying many forms of experience-dependent plasticity (i.e., long-term potentiation of synaptic currents) and also enhance experience-dependent learning in healthy adult humans. This suggests exciting possibilities for manipulating plasticity in adults and has implications for treating neurological and neuropsychiatric disorders in which experience-dependent plasticity is impaired.

Abstract

Experience-dependent plasticity is a fundamental property of the brain. It is critical for everyday function, is impaired in a range of neurological and psychiatric disorders, and frequently depends on long-term potentiation (LTP). Preclinical studies suggest that augmenting N-methyl-D-aspartate receptor (NMDAR) signaling may promote experience-dependent plasticity; however, a lack of noninvasive methods has limited our ability to test this idea in humans until recently. We examined the effects of enhancing NMDAR signaling using D-cycloserine (DCS) on a recently developed LTP EEG paradigm that uses high-frequency visual stimulation (HFvS) to induce neural potentiation in visual cortex neurons, as well as on three cognitive tasks: a weather prediction task (WPT), an information integration task (IIT), and a n-back task. The WPT and IIT are learning tasks that require practice with feedback to reach optimal performance. The n-back assesses working memory. Healthy adults were randomized to receive DCS (100 mg; n = 32) or placebo (n = 33); groups were similar in IQ and demographic characteristics. Participants who received DCS showed enhanced potentiation of neural responses following repetitive HFvS, as well as enhanced performance on the WPT and IIT. Groups did not differ on the n-back. Augmenting NMDAR signaling using DCS therefore enhanced activity-dependent plasticity in human adults, as demonstrated by lasting enhancement of neural potentiation following repetitive HFvS and accelerated acquisition of two learning tasks. Results highlight the utility of considering cellular mechanisms underlying distinct cognitive functions when investigating potential cognitive enhancers.

Negative evaluation of counterstereotypical people by conservatives maintains their sense of certainty

Yet another study on differences in the psychology of conservative and liberal individuals:

People frequently use physical appearance stereotypes to categorize individuals when their group membership is not directly observable. Recent research indicates that political conservatives tend to use such stereotypes more than liberals do because they express a greater desire for certainty and order. In the present research, we found that conservatives were also more likely to negatively evaluate and distribute fewer economic resources to people who deviate from the stereotypes of their group. This occurred for people belonging to both preexisting and novel groups, regardless of whether the stereotypes were real or experimentally fabricated. Critically, conservatives only negatively evaluated counterstereotypical people when the stereotypes were functional—that is, when they expected that they would need to use the stereotypes at a later point to categorize individuals into groups. Moreover, increasing liberals’ desire for certainty led them to negatively evaluate counterstereotypical people just like conservatives did. Thus, conservatives are not only more likely to use stereotypes than are liberals, but are especially likely to negatively evaluate counterstereotypical people to organize the social world with greater certainty.

Dorsal and Ventral Right Brain Pathways for Prosody

Sammler et al. show that analysis of the emotional content, or vocal tone, of our speech is processed in dorsal and ventral streams of the right hemisphere much as phonology, syntax, and semantics are processed by dorsal and ventral streams of the left hemisphere:

Our vocal tone—the prosody—contributes a lot to the meaning of speech beyond the actual words. Indeed, the hesitant tone of a “yes” may be more telling than its affirmative lexical meaning. The human brain contains dorsal and ventral processing streams in the left hemisphere that underlie core linguistic abilities such as phonology, syntax, and semantics. Whether or not prosody — a reportedly right-hemispheric faculty — involves analogous processing streams is a matter of debate. Functional connectivity studies on prosody leave no doubt about the existence of such streams, but opinions diverge on whether information travels along dorsal or ventral pathways. Here we show, with a novel paradigm using audio morphing combined with multimodal neuroimaging and brain stimulation, that prosody perception takes dual routes along dorsal and ventral pathways in the right hemisphere. In experiment 1, categorization of speech stimuli that gradually varied in their prosodic pitch contour (between statement and question) involved (1) an auditory ventral pathway along the superior temporal lobe and (2) auditory-motor dorsal pathways connecting posterior temporal and inferior frontal/premotor areas. In experiment 2, inhibitory stimulation of right premotor cortex as a key node of the dorsal stream decreased participants’ performance in prosody categorization, arguing for a motor involvement in prosody perception. These data draw a dual-stream picture of prosodic processing that parallels the established left-hemispheric multi-stream architecture of language, but with relative rightward asymmetry.