Subgroups of gay men correspond to different biodevelopmental pathways

Swift-Gallant et al. consider three established biomarkers of sexual orientation and suggest they reflect distinct biodevelopmental pathways influencing same-sex sexual orientation in men. They describe these biomarkers in their introduction:

A well-established biomarker of sexual orientation is familiality of male same-sex sexual orientation. Same-sex sexual orientation clusters in families, twin studies show greater sexual orientation concordance among monozygotic than dizygotic twins, and molecular genetic studies have identified candidate genes associated with sexual orientation.

A second well-studied biomarker of sexual orientation is handedness. Although the biological underpinnings of handedness are not yet clear, increasing evidence suggests that handedness is a marker of cerebral lateralization determined prenatally by genetic, immunological, and endocrine mechanisms and/or by developmental instability... it is estimated that men have 20% greater odds of non−right-handedness than women, and gay men have 34% greater odds of being non−right-handed than heterosexual men.

A third well-established biomarker of sexual orientation is the fraternal birth order effect). Across a diverse range of cultures and sample types, studies have shown that older brothers increase the odds of androphilia in later-born males. The maternal immune hypothesis is the best-developed explanation of the fraternal birth order effect. It argues that male antigens enter maternal circulation during the gestation and birthing of male offspring, promoting an immune response to these male-specific antigens that increases with each successive male fetus gestated; thus, with each successive pregnancy with a male fetus, the odds increase that these maternal antibodies will affect sexual differentiation of the brain and behavior, including sexual preferences.

Their Significance and Abstract statements:  

Significance

Studying individual differences in gender and sexual orientation provides insight into how early-life biology shapes brain and behavior. The literature identifies multiple biodevelopmental influences on male sexual orientation, but these influences are generally studied individually, and the potential for association or interaction between them remains largely unexplored. We hypothesized that distinct biodevelopmental pathways correspond to specific subgroups of nonheterosexual men. We present evidence that nonheterosexual men can be categorized into at least four subgroups based on established biomarkers, and these biodevelopmental pathways differentially relate to gender expression and personality traits. These findings indicate individual differences in biodevelopmental pathways of male sexual orientation. They also illustrate the value of latent profile analyses for studying individual differences.

Abstract

Several biological mechanisms have been proposed to influence male sexual orientation, but the extent to which these mechanisms cooccur is unclear. Putative markers of biological processes are often used to evaluate the biological basis of male sexual orientation, including fraternal birth order, handedness, and familiality of same-sex sexual orientation; these biomarkers are proxies for immunological, endocrine, and genetic mechanisms. Here, we used latent profile analysis (LPA) to assess whether these biomarkers cluster within the same individuals or are present in different subgroups of nonheterosexual men. LPA defined four profiles of men based on these biomarkers: 1) A subgroup who did not have these biomarkers, 2) fraternal birth order, 3) handedness, and 4) familiality. While the majority of both heterosexual and nonheterosexual men were grouped in the profile that did not have any biomarker, the three profiles associated with a biomarker were composed primarily of nonheterosexual men. We then evaluated whether these subgroups differed on measures of gender nonconformity and personality that reliably show male sexual orientation differences. The subgroup without biomarkers was the most gender-conforming whereas the fraternal birth order subgroup was the most female-typical and agreeable, compared with the other profiles. Together, these findings suggest there are multiple distinct biodevelopmental pathways influencing same-sex sexual orientation in men.

Social Media - no effect on adolescent life satisfaction?

Orben et al. (open source article) provide a study whose results contest a common opinion, reinforced by several previous studies, that adolescents who use social media extensively are more likely to be depressed and have low self esteem. They used...

...large-scale representative panel data to disentangle the between-person and within-person relations linking adolescent social media use and well-being. We found that social media use is not, in and of itself, a strong predictor of life satisfaction across the adolescent population. Instead, social media effects are nuanced, small at best, reciprocal over time, gender specific, and contingent on analytic methods.

They note limitations of current published research:

Focused on cross-sectional relations, scientists have few means of parsing longitudinal effects from artifacts introduced by common statistical modeling methodologies. Furthermore, the volume of data under analysis, paired with unchecked analytical flexibility, enables selective research reporting, biasing the literature toward statistically significant effects. Nevertheless, trivial trends are routinely overinterpreted by those under increasing pressure to rapidly craft evidence-based policies.

The UK study examined data on 12,672 10-15 year old. Two summary graphics are provided. One clip:

...the importance of gender was apparent: Only 16% of significant models arose from male data.

The last two paragraphs:

The relations linking social media use and life satisfaction are, therefore, more nuanced than previously assumed: They are inconsistent, possibly contingent on gender, and vary substantively depending on how the data are analyzed. Most effects are tiny—arguably trivial; where best statistical practices are followed, they are not statistically significant in more than half of models. That understood, some effects are worthy of further exploration and replication: There might be small reciprocal within-person effects in females, with increases in life satisfaction predicting slightly lower social media use, and increases in social media use predicting tenuous decreases in life satisfaction.

With the unknowns of social media effects still substantially outnumbering the knowns, it is critical that independent scientists, policymakers, and industry researchers cooperate more closely. Scientists must embrace circumspection, transparency, and robust ways of working that safeguard against bias and analytical flexibility. Doing so will provide parents and policymakers with the reliable insights they need on a topic most often characterized by unfounded media hype. Finally, and most importantly, social media companies must support independent research by sharing granular user engagement data and participating in large-scale team-based open science. Only then will we truly unravel the complex constellations of effects shaping young people in the digital age.

Think twice about metformin as an anti-aging drug.

Gretchen Reynolds points to work suggesting that use of metformin (the most commonly used Type 2 diabetes drug) as an anti-aging agent by healthy active people (because it reduces inflammation and causes other cellular effects that alter aging) may have a downside. Konopka et al. report that it suppresses the anti-aging effects of exercise, notably exercise-related gains in muscle-cell mitochondrial respiration. There is the usual caveat that this is a single study with a relatively small number of subjects (53). Here is their technical abstract:

Metformin and exercise independently improve insulin sensitivity and decrease the risk of diabetes. Metformin was also recently proposed as a potential therapy to slow aging. However, recent evidence indicates that adding metformin to exercise antagonizes the exercise‐induced improvement in insulin sensitivity and cardiorespiratory fitness. The purpose of this study was to test the hypothesis that metformin diminishes the improvement in insulin sensitivity and cardiorespiratory fitness after aerobic exercise training (AET) by inhibiting skeletal muscle mitochondrial respiration and protein synthesis in older adults (62 ± 1 years). In a double‐blinded fashion, participants were randomized to placebo (n = 26) or metformin (n = 27) treatment during 12 weeks of AET. Independent of treatment, AET decreased fat mass, HbA1c, fasting plasma insulin, 24‐hr ambulant mean glucose, and glycemic variability. However, metformin attenuated the increase in whole‐body insulin sensitivity and VO2max after AET. In the metformin group, there was no overall change in whole‐body insulin sensitivity after AET due to positive and negative responders. Metformin also abrogated the exercise‐mediated increase in skeletal muscle mitochondrial respiration. The change in whole‐body insulin sensitivity was correlated to the change in mitochondrial respiration. Mitochondrial protein synthesis rates assessed during AET were not different between treatments. The influence of metformin on AET‐induced improvements in physiological function was highly variable and associated with the effect of metformin on the mitochondria. These data suggest that prior to prescribing metformin to slow aging, additional studies are needed to understand the mechanisms that elicit positive and negative responses to metformin with and without exercise.

Your professional decline.

Arthur Brooks, former president of the conservative American Enterprise Institute think tank and New York Times Op-Ed writer, does an essay in the Atlantic in which he contemplates his professional decline, making points that are universally relevant. Some clips:

...happiness of most adults declines through their 30s and 40s, then bottoms out in their early 50s...Almost all studies of happiness over the life span show that, in wealthier countries, most people’s contentment starts to increase again in their 50s, until age 70 or so. That is where things get less predictable, however. After 70, some people stay steady in happiness; others get happier until death. Others—men in particular—see their happiness plummet. Indeed, depression and suicide rates for men increase after age 75...A few researchers have looked at this cohort to understand what drives their unhappiness. It is, in a word, irrelevance.

This is especially an issue in gifted and accomplished people.

...accomplishment is a well-documented source of happiness. If current accomplishment brings happiness, then shouldn’t the memory of that accomplishment provide some happiness as well?...Though the literature on this question is sparse, giftedness and achievements early in life do not appear to provide an insurance policy against suffering later on...abundant evidence suggests that the waning of ability in people of high accomplishment is especially brutal psychologically...Call it the Principle of Psychoprofessional Gravitation: the idea that the agony of professional oblivion is directly related to the height of professional prestige previously achieved, and to one’s emotional attachment to that prestige...the memory of remarkable ability, if that is the source of one’s self-worth, might, for some, provide an invidious contrast to a later, less remarkable life.

In some professions, early decline is inescapable. No one expects an Olympic athlete to remain competitive until age 60. But in many physically nondemanding occupations, we implicitly reject the inevitability of decline before very old age. Sure, our quads and hamstrings may weaken a little as we age. But as long as we retain our marbles, our quality of work as a writer, lawyer, executive, or entrepreneur should remain high up to the very end, right? ...The data are shockingly clear that for most people, in most fields, decline starts earlier than almost anyone thinks...if you start a career in earnest at 30, expect to do your best work around 50 and go into decline soon after that...the most common age for producing a magnum opus is the late 30s...the likelihood of a major discovery increases steadily through one’s 20s and 30s and then declines through one’s 40s, 50s, and 60s. Are there outliers? Of course. But the likelihood of producing a major innovation at age 70 is approximately what it was at age 20—almost nonexistent.

In sum, if your profession requires mental processing speed or significant analytic capabilities—the kind of profession most college graduates occupy—noticeable decline is probably going to set in earlier than you imagine...Whole sections of bookstores are dedicated to becoming successful. The shelves are packed with titles like The Science of Getting Rich and The 7 Habits of Highly Effective People. There is no section marked “Managing Your Professional Decline.”

Brooks contrasts the declines of Charles Darwin, who became embittered and inactive after his younger most creative period had passed, with Johann Sebastian Bach, who redesigned his life - as baroque music was being replaced by the "classical" style - moving from being an innovator to being a teacher and instructor.

The lesson for you and me, especially after 50: Be Johann Sebastian Bach, not Charles Darwin...How does one do that? A potential answer lies in the work of the British psychologist Raymond Cattell, who in the early 1940s introduced the concepts of fluid and crystallized intelligence. Cattell defined fluid intelligence as the ability to reason, analyze, and solve novel problems—what we commonly think of as raw intellectual horsepower. ...It is highest relatively early in adulthood and diminishes starting in one’s 30s and 40s...Crystallized intelligence, in contrast, is the ability to use knowledge gained in the past. Think of it as possessing a vast library and understanding how to use it. It is the essence of wisdom. Because crystallized intelligence relies on an accumulating stock of knowledge, it tends to increase through one’s 40s, and does not diminish until very late in life...poets—highly fluid in their creativity—tend to have produced half their lifetime creative output by age 40 or so. Historians—who rely on a crystallized stock of knowledge—don’t reach this milestone until about 60...No matter what mix of intelligence your field requires, you can always endeavor to weight your career away from innovation and toward the strengths that persist, or even increase, later in life...teaching is an ability that decays very late in life, a principal exception to the general pattern of professional decline over time...the most profound insights tend to come from those in their 30s and early 40s. The best synthesizers and explainers of complicated ideas—that is, the best teachers—tend to be in their mid-60s or older, some of them well into their 80s.

Most Eastern philosophy warns that focusing on acquisition leads to attachment and vanity, which derail the search for happiness by obscuring one’s essential nature. As we grow older, we shouldn’t acquire more, but rather strip things away to find our true selves—and thus, peace.

At some point, writing one more book will not add to my life satisfaction; it will merely stave off the end of my book-writing career. The canvas of my life will have another brushstroke that, if I am being forthright, others will barely notice, and will certainly not appreciate very much. The same will be true for most other markers of my success.

What I need to do, in effect, is stop seeing my life as a canvas to fill, and start seeing it more as a block of marble to chip away at and shape something out of. I need a reverse bucket list. My goal for each year of the rest of my life should be to throw out things, obligations, and relationships until I can clearly see my refined self in its best form.

Hindu philosophy—and indeed the wisdom of many philosophical traditions—suggests that you should be prepared to walk away from the rewards of success before you feel ready. Even if you’re at the height of your professional prestige, you probably need to scale back your career ambitions in order to scale up your metaphysical ones.

David Brooks talks about the difference between “résumé virtues” and “eulogy virtues,”...Résumé virtues are professional and oriented toward earthly success. They require comparison with others. Eulogy virtues are ethical and spiritual, and require no comparison. Your eulogy virtues are what you would want people to talk about at your funeral. As in He was kind and deeply spiritual, not He made senior vice president at an astonishingly young age and had a lot of frequent-flier miles....To move from résumé virtues to eulogy virtues is to move from activities focused on the self to activities focused on others.

..an abundance of research strongly suggests that happiness—not just in later years but across the life span—is tied directly to the health and plentifulness of one’s relationships. Pushing work out of its position of preeminence—sooner rather than later—to make space for deeper relationships can provide a bulwark against the angst of professional decline.

The aspen tree is an excellent metaphor for a successful person—but not, it turns out, for its solitary majesty. Above the ground, it may appear solitary. Yet each individual tree is part of an enormous root system, which is together one plant...The secret to bearing my decline—to enjoying it—is to become more conscious of the roots linking me to others. If I have properly developed the bonds of love among my family and friends, my own withering will be more than offset by blooming in others.

Perception as controlled hallucination - predictive processing and the nature of conscious experience

I've now read several times through a fascinating Edge.org conversation with philosopher Andy Clark. I suggest you read the piece, and here pass on some edited clips. First, his comments on most current A.I. efforts:

There's something rather passive about the kinds of artificial intelligence ...[that are]...trained on an objective function. The AI tries to do a particular thing for which it might be exposed to an awful lot of data in trying to come up with ways to do this thing. But at the same time, it doesn't seem to inhabit bodies or inhabit worlds; it is solving problems in a disembodied, disworlded space. The nature of intelligence looks very different when we think of it as a rolling process that is embedded in bodies or embedded in worlds. Processes like that give rise to real understandings of a structured world.

Then, his ideas on how our internal and external worlds are a continuum:

Perception itself is a kind of controlled hallucination. You experience a structured world because you expect a structured world, and the sensory information here acts as feedback on your expectations. It allows you to often correct them and to refine them. But the heavy lifting seems to be being done by the expectations. Does that mean that perception is a controlled hallucination? I sometimes think it would be good to flip that and just think that hallucination is a kind of uncontrolled perception.

The Bayesian brain, predictive processing, hierarchical predictive coding are all, roughly speaking, names for the same picture in which experience is constructed at the shifting borderline between sensory evidence and top-down prediction or expectation. There's been a big literature out there on the perceptual side of things. It's a fairly solid literature. What predictive processing did that I found particularly interesting—and this is mostly down to a move that was made by Karl Friston—was apply the same story to action. In action, what we're doing is making a certain set of predictions about the shape of the sensory information that would result if I were to perform the action. Then you get rid of prediction errors relative to that predicted flow by making the action.

There's a pleasing symmetry there. Once you've got action on the table in these stories—the idea is that we bring action about by predicting sensory flows that are non actual and then getting rid of prediction errors relative to those sensory flows by bringing the action about—that means that epistemic action, as it's sometimes called, is right there on the table. Systems like that cannot just act in the world to fulfill their goals; they can also act in the world so as to get better information to fulfill their goals. And that's something that active animals do all the time. The chicken, when it bobs its head around, is moving its sensors around to get information that allows it to do depth perception that it can't do unless it bobs its head around...Epistemic action, and practical action, and perception, and understanding are now all rolled together in this nice package.

An upshot here is that there's no experience without the application of some model to try to sift what is worthwhile for a creature like you in the signal and what isn't worthwhile for a creature like you.

Apart from the exteroceptive signals that we take in from vision, sound, and so on, and apart from the proprioceptive signals from our body that are what we predict in order to move our body around, there's also all of the interoceptive signals that are coming from the heart and from the viscera, et cetera...being subtly inflected by interoception information is part of what makes our conscious experience of the world the kind of experience that it is. So, artificial systems without interoception could perceive their world in an exteroceptive way, they could act in their world, but they would be lacking what seems to me to be one important dimension of what it is to be a conscious human being in the world.

Implicit racial bias is preserved by historical roots of social environments.

Payne et al. note that geographic differences in implicit racial bias correlate with the number of slaves in those areas in 1860.

Significance

Geographic variation in implicit bias is associated with multiple racial disparities in life outcomes. We investigated the historical roots of geographical differences in implicit bias by comparing average levels of implicit bias with the number of slaves in those areas in 1860. Counties and states more dependent on slavery in 1860 displayed higher pro-White implicit bias today among White residents and less pro-White bias among Black residents. Mediation analyses suggest that historical oppression may be transmitted into contemporary biases through structural inequalities, including disparities in poverty and upward mobility. Given the importance of contextual factors, efforts to reduce unintended discrimination might focus on modifying social environments that cue implicit biases in the minds of individuals.

Abstract

Implicit racial bias remains widespread, even among individuals who explicitly reject prejudice. One reason for the persistence of implicit bias may be that it is maintained through structural and historical inequalities that change slowly. We investigated the historical persistence of implicit bias by comparing modern implicit bias with the proportion of the population enslaved in those counties in 1860. Counties and states more dependent on slavery before the Civil War displayed higher levels of pro-White implicit bias today among White residents and less pro-White bias among Black residents. These associations remained significant after controlling for explicit bias. The association between slave populations and implicit bias was partially explained by measures of structural inequalities. Our results support an interpretation of implicit bias as the cognitive residue of past and present structural inequalities.

Over 50-fold difference between individuals in circadian melatonin sensitivity to evening light.

Phillips et al. probe how our high sensitivity to artificial light after dusk perturbs the circadian rhythm of our sleep hormone melatonin:

Significance

Electric lighting has fundamentally altered how the human circadian clock synchronizes to the day/night cycle. Exposure to light after dusk is pervasive in the modern world. We examined group-level sensitivity of the circadian system to evening light and the degree to which sensitivity varies between individuals. We found that, on average, humans are highly sensitive to evening light. Specifically, 50% suppression of melatonin occurred at less than 30 lux, which is comparable to or lower than typical indoor lighting used at night, as well as light produced by electronic devices. Significantly, there was a greater than 50-fold difference in sensitivity to evening light across individuals. Interindividual differences in light sensitivity may explain differential vulnerability to circadian disruption and subsequent impact on human health.

Abstract

Before the invention of electric lighting, humans were primarily exposed to intense (>300 lux) or dim (less than 30 lux) environmental light—stimuli at extreme ends of the circadian system’s dose–response curve to light. Today, humans spend hours per day exposed to intermediate light intensities (30–300 lux), particularly in the evening. Interindividual differences in sensitivity to evening light in this intensity range could therefore represent a source of vulnerability to circadian disruption by modern lighting. We characterized individual-level dose–response curves to light-induced melatonin suppression using a within-subjects protocol. Fifty-five participants (aged 18–30) were exposed to a dim control (less than 1 lux) and a range of experimental light levels (10–2,000 lux for 5 h) in the evening. Melatonin suppression was determined for each light level, and the effective dose for 50% suppression (ED₅₀) was computed at individual and group levels. The group-level fitted ED₅₀ was 24.60 lux, indicating that the circadian system is highly sensitive to evening light at typical indoor levels. Light intensities of 10, 30, and 50 lux resulted in later apparent melatonin onsets by 22, 77, and 109 min, respectively. Individual-level ED₅₀ values ranged by over an order of magnitude (6 lux in the most sensitive individual, 350 lux in the least sensitive individual), with a 26% coefficient of variation. These findings demonstrate that the same evening-light environment is registered by the circadian system very differently between individuals. This interindividual variability may be an important factor for determining the circadian clock’s role in human health and disease.

Mechanism of exercise and antioxidant stimulation of memory and new nerve cell growth

On reading this article by Yook et al. I promptly ordered a bottle of 10 mg astaxanthin capsules to add to my normal array of supplements (and exercise).

Significance

Leptin (LEP, a small protein hormone), produced and acting in the hippocampus, mediates enhancement by mild exercise (ME) of hippocampus-related memory and neurogenesis, which are further increased by an antioxidant carotenoid, astaxanthin (AX). Both are facilitated by the administration of ME or AX alone. The up-regulation of the LEP gene and LEP protein expression in the hippocampus by ME is further elevated when combined with AX. Consistently, the combined interventions increased hippocampal LEP protein. In LEP-deficient ob/ob mice, LEP replacement in the brain restored the ability of ME+AX to enhance hippocampal function. Thus, a combined lifestyle intervention based on ME, including yoga and tai chi, and specific dietary supplements that include antioxidants may together improve cognition and possibly retard cognitive decline in humans.

Abstract

Regular exercise and dietary supplements with antioxidants each have the potential to improve cognitive function and attenuate cognitive decline, and, in some cases, they enhance each other. Our current results reveal that low-intensity exercise (mild exercise, ME) and the natural antioxidant carotenoid astaxanthin (AX) each have equivalent beneficial effects on hippocampal neurogenesis and memory function. We found that the enhancement by ME combined with AX in potentiating hippocampus-based plasticity and cognition is mediated by leptin (LEP) made and acting in the hippocampus. In assessing the combined effects upon wild-type (WT) mice undergoing ME with or without an AX diet for four weeks, we found that, when administrated alone, ME and AX separately enhanced neurogenesis and spatial memory, and when combined they were at least additive in their effects. DNA microarray and bioinformatics analyses revealed not only the up-regulation of an antioxidant gene, ABHD3, but also that the up-regulation of LEP gene expression in the hippocampus of WT mice with ME alone is further enhanced by AX. Together, they also increased hippocampal LEP (h-LEP) protein levels and enhanced spatial memory mediated through AKT/STAT3 signaling. AX treatment also has direct action on human neuroblastoma cell lines to increase cell viability associated with increased LEP expression. In LEP-deficient mice (ob/ob), chronic infusion of LEP into the lateral ventricles restored the synergy. Collectively, our findings suggest that not only h-LEP but also exogenous LEP mediates effects of ME on neural functions underlying memory, which is further enhanced by the antioxidant AX.

Enhancing longevity by removing deteriorated body cells.

Here I pass on both the introductory summary and concluding paragraph of van Deursen's review of efforts to enhance longevity by removing body cells that have deteriorated and become dysfunctional (SNCs).

The estimated “natural” life span of humans is ∼30 years, but improvements in working conditions, housing, sanitation, and medicine have extended this to ∼80 years in most developed countries. However, much of the population now experiences aging-associated tissue deterioration. Healthy aging is limited by a lack of natural selection, which favors genetic programs that confer fitness early in life to maximize reproductive output. There is no selection for whether these alterations have detrimental effects later in life. One such program is cellular senescence, whereby cells become unable to divide. Cellular senescence enhances reproductive success by blocking cancer cell proliferation, but it decreases the health of the old by littering tissues with dysfunctional senescent cells (SNCs). In mice, the selective elimination of SNCs (senolysis) extends median life span and prevents or attenuates age-associated diseases. This has inspired the development of targeted senolytic drugs to eliminate the SNCs that drive age-associated disease in humans.

As knowledge of the fundamental biology and vulnerabilities of SNCs expands, the rational design of targeted senolytics is expected to yield therapies to eliminate SNCs that drive degeneration and disease. This positive outlook is based on successes in oncology and because the main limitation of cancer therapies—the clonal expansion of drug-resistant cells—does not apply to SNCs. Additional confidence comes from the recent progress in bringing senolytic agents into clinical trials. The first clinical trial is testing UBX0101 for the treatment of osteoarthritis of the knee. Another drug, UBX1967, a BCL-2 family inhibitor specifically tailored for diseases of the aging eye, is also advancing to human testing. Multiple clinical trials treating diverse diseases of aging with senolytic drugs are expected to follow soon. This includes two-step cancer treatment approaches whereby malignant cells are first forced into a senescent state by one drug and then eliminated with a senolytic agent. Success in these first clinical studies is the next critical milestone on the road to the development of treatments that can extend healthy longevity in people.

Why can we read only one word at a time?

Fascinating work from White et al.:

Significance

Because your brain has limited processing capacity, you cannot comprehend the text on this page all at once. In fact, skilled readers cannot even recognize just two words at once. We measured how the visual areas of the brain respond to pairs of words while participants attended to one word or tried to divide attention between both. We discovered that a single word-selective region in left ventral occipitotemporal cortex processes both words in parallel. The parallel streams of information then converge at a bottleneck in an adjacent, more anterior word-selective region. This result reveals the functional significance of subdivisions within the brain’s reading circuitry and offers a compelling explanation for a profound limit on human perception.

Abstract

In most environments, the visual system is confronted with many relevant objects simultaneously. That is especially true during reading. However, behavioral data demonstrate that a serial bottleneck prevents recognition of more than one word at a time. We used fMRI to investigate how parallel spatial channels of visual processing converge into a serial bottleneck for word recognition. Participants viewed pairs of words presented simultaneously. We found that retinotopic cortex processed the two words in parallel spatial channels, one in each contralateral hemisphere. Responses were higher for attended than for ignored words but were not reduced when attention was divided. We then analyzed two word-selective regions along the occipitotemporal sulcus (OTS) of both hemispheres (subregions of the visual word form area, VWFA). Unlike retinotopic regions, each word-selective region responded to words on both sides of fixation. Nonetheless, a single region in the left hemisphere (posterior OTS) contained spatial channels for both hemifields that were independently modulated by selective attention. Thus, the left posterior VWFA supports parallel processing of multiple words. In contrast, activity in a more anterior word-selective region in the left hemisphere (mid OTS) was consistent with a single channel, showing (i) limited spatial selectivity, (ii) no effect of spatial attention on mean response amplitudes, and (iii) sensitivity to lexical properties of only one attended word. Therefore, the visual system can process two words in parallel up to a late stage in the ventral stream. The transition to a single channel is consistent with the observed bottleneck in behavior.

Why high-class people get away with incompetence.

Belmi et al. do four experiments suggesting that people who come from a higher social class are more likely to have an inflated sense of their skills — even when tests proved that they are average. This unmerited overconfidence is interpreted by strangers as competence. This highlights yet another way that family wealth and parents' education confers an advantage in getting ahead in life.

Understanding how socioeconomic inequalities perpetuate is a central concern among social and organizational psychologists. Drawing on a collection of findings suggesting that different social class contexts have powerful effects on people’s sense of self, we propose that social class shapes the beliefs that people hold about their abilities, and that this, in turn, has important implications for how status hierarchies perpetuate. We first hypothesize that compared with individuals with relatively low social class, individuals with relatively high social class are more overconfident. Then, drawing on research suggesting that overconfidence can confer social advantages, we further hypothesize that the overconfidence of higher class individuals can help perpetuate the existing class hierarchy: It can provide them a path to social advantage by making them appear more competent in the eyes of others. We test these ideas in four large studies with a combined sample of 152,661 individuals. Study 1, a large field study featuring small-business owners from Mexico, found evidence that individuals with relatively high social class are more overconfident compared with their lower-class counterparts. Study 2, a multiwave study in the United States, replicated this result and further shed light on the underlying mechanism: Individuals with relatively high (vs. low) social class tend to be more overconfident because they have a stronger desire to achieve high social rank. Study 3 replicated these findings in a high-powered, preregistered study and found that individuals with relatively high social class were more overconfident, even in a task in which they had no performance advantages. Study 4, a multiphase study that featured a mock job interview in the laboratory, found that compared with their lower-class counterparts, higher-class individuals were more overconfident; overconfidence, in turn, made them appear more competent and more likely to attain social rank.

Policy evaluation by randomized trials may provoke greater objections than implementing them untested.

Meyer et al. find that experiments comparing two unobjectionable policies or treatments can generate more objections than simply proceeding to implement them.

Significance

Randomized experiments—long the gold standard in medicine—are increasingly used throughout the social sciences and professions to evaluate business products and services, government programs, education and health policies, and global aid. We find robust evidence—across 16 studies of 5,873 participants from three populations spanning nine domains—that people often approve of untested policies or treatments (A or B) being universally implemented but disapprove of randomized experiments (A/B tests) to determine which of those policies or treatments is superior. This effect persists even when there is no reason to prefer A to B and even when recipients are treated unequally and randomly in all conditions (A, B, and A/B). This experimentation aversion may be an important barrier to evidence-based practice.

Abstract

Randomized experiments have enormous potential to improve human welfare in many domains, including healthcare, education, finance, and public policy. However, such “A/B tests” are often criticized on ethical grounds even as similar, untested interventions are implemented without objection. We find robust evidence across 16 studies of 5,873 participants from three diverse populations spanning nine domains—from healthcare to autonomous vehicle design to poverty reduction—that people frequently rate A/B tests designed to establish the comparative effectiveness of two policies or treatments as inappropriate even when universally implementing either A or B, untested, is seen as appropriate. This “A/B effect” is as strong among those with higher educational attainment and science literacy and among relevant professionals. It persists even when there is no reason to prefer A to B and even when recipients are treated unequally and randomly in all conditions (A, B, and A/B). Several remaining explanations for the effect—a belief that consent is required to impose a policy on half of a population but not on the entire population; an aversion to controlled but not to uncontrolled experiments; and a proxy form of the illusion of knowledge (according to which randomized evaluations are unnecessary because experts already do or should know “what works”)—appear to contribute to the effect, but none dominates or fully accounts for it. We conclude that rigorously evaluating policies or treatments via pragmatic randomized trials may provoke greater objection than simply implementing those same policies or treatments untested.

Is technology really reshaping our consciousness?

My first reaction on reading a recent Op-Ed piece by David Brooks "When Trolls and Crybullies Rule the Earth" was to say 'Yes!', and think I should immediately fire off some selected clips in a MindBlog post. I'm glad I waited a bit, because as I look at it again I feel he has erred on the side of being an alarmist drama queen to grab our attention. The article begins with:

Over the past several years, teenage suicide rates have spiked horrifically....What's going on?

Several sources show an increasing rate from 2010 to 2017, but a look at Centers for Disease Control data shows higher rates for the late 1980's and early 1990's. He continues:

My answer starts with technology but is really about the sort of consciousness online life induces.

Brooks then describes transformations of human consciousness as if they have replaced, rather than adding to and enhancing, older forms of consciousness:  the shift from an oral to a printed culture centuries ago and the current shift from printed to electronic communication.

Attention and affection have gone from being private bonds to being publicly traded goods...up until recently most of the attention a person received came from family and friends and was pretty stable. But now most of the attention a person receives can come from far and wide and is tremendously volatile...your online post can go viral and get massively admired or ridiculed, while other times your post can leave you alone and completely ignored. Communication itself, once mostly collaborative, is now often competitive, with bids for affection and attention. It is also more manipulative — gestures designed to generate a response.

But... were not the old fashioned kinds of attention exchanged personally or in crowds of people, rather than electronically, labile and competitive with constant bids for affection and attention? Electronics may have amplified what was happening, but it didn't fundamentally transform it. Vicious gossip can be exchanged in old fashioned personal or newer less personal electronic ways. Online platforms may be an amplifier of our traits, but they don't basically transform them. Trolls and crybullies have always been with us. Still, Brooks makes good points, even if a bit exaggerated:

The internet has become a place where people communicate out of their competitive ego: I’m more fabulous than you (a lot of Instagram). You’re dumber than me (much of Twitter). It’s not a place where people share from their hearts and souls.

Of course, people enmeshed in such a climate are more likely to feel depressed, to suffer from mental health problems. Of course, they are more likely to see human relationship through the abuser/victim frame, and to be acutely sensitive to any power imbalance. Imagine you’re 17 and people you barely know are saying nice or nasty things about your unformed self. It creates existential anxiety and hence fanaticism.

The wisdom of partisan crowds.

Fascinating and counterintuitive findings from Becker et al., who find that the wisdom of crowds is robust to partisan bias:

Significance

Normative theories of deliberative democracy are based on the premise that social information processing can improve group beliefs. Research on the “wisdom of crowds” has found that information exchange can increase belief accuracy in many cases, but theories of political polarization imply that groups will become more extreme—and less accurate—when beliefs are motivated by partisan political bias. While this risk is not expected to emerge in politically heterogeneous networks, homogeneous social networks are expected to amplify partisan bias when people communicate only with members of their own political party. However, we find that the wisdom of crowds is robust to partisan bias. Social influence not only increases accuracy but also decreases polarization without between-group network ties.

Abstract

Theories in favor of deliberative democracy are based on the premise that social information processing can improve group beliefs. While research on the “wisdom of crowds” has found that information exchange can increase belief accuracy on noncontroversial factual matters, theories of political polarization imply that groups will become more extreme—and less accurate—when beliefs are motivated by partisan political bias. A primary concern is that partisan biases are associated not only with more extreme beliefs, but also with a diminished response to social information. While bipartisan networks containing both Democrats and Republicans are expected to promote accurate belief formation, politically homogeneous networks are expected to amplify partisan bias and reduce belief accuracy. To test whether the wisdom of crowds is robust to partisan bias, we conducted two web-based experiments in which individuals answered factual questions known to elicit partisan bias before and after observing the estimates of peers in a politically homogeneous social network. In contrast to polarization theories, we found that social information exchange in homogeneous networks not only increased accuracy but also reduced polarization. Our results help generalize collective intelligence research to political domains.

Inequality brokered

Public opinion about sexual minorities has improved dramatically in recent years, but Sun and Gao do an analysis showing that discriminatory behavior in lending practices has been ongoing and gone unchecked.

Significance

We propose a method to infer people’s sexual orientation indirectly through gender disclosure of the borrower and coborrower in a mortgage. Furthermore, we examine lending practices toward same-sex borrowers and its spillover effects. We attempt to extend the research on race/gender discrimination by systematically investigating the potentially different lending treatment toward same-sex borrowers. The data reveal that, compared with otherwise similar different-sex applicants, same-sex applicants are 73.12% more likely to be denied, and they tend to be charged up to 0.2% higher fees/interest. Furthermore, neighborhoods’ higher same-sex population density adversely affects both same-sex and different-sex borrowers’ lending experiences. Our method might approximately measure the US homosexual population distribution up to the census tract level annually over decades.

Abstract

Using massive US mortgage lending data, we propose a method to infer a borrower’s sexual orientation indirectly without a self-identification requirement and demonstrate the method’s potential to approximately measure the sexual orientation of the US population at the local level annually over decades. We continue to examine the lending practices to same-sex borrowers and its spillover effects. The persistent results since 1990 reveal that, in contrast with otherwise comparable different-sex loan applicants, the approval rate for same-sex applicants is ∼3–8% lower. Furthermore, conditional on approval, lenders, on average, charge about 0.02–0.2% higher interest to same-sex borrowers, which is equivalent to an annual total of $8.6 million to $86 million in additional interest/fees nationwide. Meanwhile, we find that same-sex borrowers are less risky overall, as they exhibit similar default risk but lower prepayment risk. Finally, we document findings of spillover effects. That is, when the share of a neighborhood’s same-sex population increases, both same-sex and different-sex borrowers seem to experience more unfavorable lending outcomes overall. The findings should raise enough concerns to warrant further investigations.

Blueprint - Nicholas Christakis' new book on evolutionary origins of a good society

This opinion piece by Frank Bruni in the NYTimes motivated me to download and read Nicholas Christakis' Magnum Opus “Blueprint” (very much in the 'everything you need to know about humans' spirit of Sapolsky's "Behave" and Harari's "Sapiens," and "Homo Deus," and "21 Lessons," all books that I have made the subject of previous posts.). It echoes Pinker's emphasis on the more positive aspects of human nature and progress. It is a very engaging read, and not amenable to a simple summary, but here is a bit from his introduction:

How can people be so different from—even go to war with—one another and yet also be so similar? The fundamental reason is that we each carry within us an evolutionary blueprint for making a good society.

Genes do amazing things inside our bodies, but even more amazing to me is what they do outside of them. Genes affect not only the structure and function of our bodies; not only the structure and function of our minds and, hence, our behaviors; but also the structure and function of our societies. This is what we recognize when we look at people around the world. This is the source of our common humanity.

Natural selection has shaped our lives as social animals, guiding the evolution of what I call a “social suite” of features priming our capacity for love, friendship, cooperation, learning, and even our ability to recognize the uniqueness of other individuals. Despite all the trappings and artifacts of modern invention—our tools, agriculture, cities, nations—we carry within us innate proclivities that reflect our natural social state, a state that is, as it turns out, primarily good, practically and even morally. Humans can no more make a society that is inconsistent with these positive urges than ants can suddenly make beehives.

I believe that we come to this sort of goodness just as naturally as we come to our bloodier inclinations. We cannot help it. We feel great when we help others. Our good deeds are not just the products of Enlightenment values. They have a deeper and prehistoric origin. The ancient tendencies that form the social suite work together to bind communities, specify their boundaries, identify their members, and allow people to achieve individual and collective objectives while at the same time minimizing hatred and violence. For too long, in my opinion, the scientific community has been overly focused on the dark side of our biological heritage: our capacity for tribalism, violence, selfishness, and cruelty. The bright side has been denied the attention it deserves.

After brief music training 8-10 year old kids show less hyperactivity and better inhibitory control.

Fasano et al. show that only three months of orchestral music training improves inhibitory control and reduces hyperactivity in 8-10 year old children. From the Science Magazine summary of Tamela Hines:

Play your notes and nothing extra. Wait during your measures of rest. Watch the conductor and synchronize with your neighbors. Such attention and sensorimotor skills are key to performing music as part of a group, whether orchestral or choral or a marching band. Not everyone, however, has the time and interest to become a professional musician. Fasano et al. tested the effect of a short orchestral training program, spanning 10 sessions over 3 months, on a group of psychologically normal schoolchildren in Italy. Children in this brief program improved on measures of inhibitory control and hyperactivity. The results suggest new, and fun, ways to help children manage their own hyperactive behaviors.

Happily ever after....

Sure enough, as soon as I do yesterday's post on aging, I run into, and will pass on in this post, a sane article in the Guardian that is basically a listicle of 25 ways to live well into old age. An explanatory paragraph accompanies each item in the list.

-Look to your ancestors for answers
-Enjoy coffee
-Walk faster
-Exercise in green space
-Fast every day
-Build muscle
-Read books
-Work longer
-Keep learning
-Take a nap
-Clean out your medicine cabinet
-Only spend on vitamin D and zinc
-Avoid pollution
-Use olive oil
-Build bone density
-Cultivate friendships
-Support Immunity (dark leafy greens, brassicas like cabbage and broccoli, alliums like garlic, leeks and onions, and mushrooms.)
-Change how you eat, particularly in the evening
-Add tumeric
-Meditate
-Eat more fiber
-Avoid blue light in the evenings
-Look after your eyes
-Walk a dog
-Cultivate optimism

Live younger longer

New Yorker Magazine writer and polymath Adam Gopnik does an excellent article describing studies on our increased longevity that aim to enhance its quality, not its duration. He also describes anti-aging research directed at increasing longevity.  I suggest you read the article. Here are a few clips, mainly from the first part of the article describing the experience of aging:

Over the past century, we’ve created the greatest gift in the history of humanity—thirty extra years of life—and we don’t know what to do with it! Now that we’re living longer, how do we plan for what we’re going to do?

To get a sense of what it would be like to have the slow process of aging become a fast process, you can go to the AgeLab, at the Massachusetts Institute of Technology, in Cambridge, and put on agnes (for Age Gain Now Empathy System). agnes, or the “sudden aging” suit, as Joseph Coughlin, the founder and director of the AgeLab describes it, includes yellow glasses, which convey a sense of the yellowing of the ocular lens that comes with age; a boxer’s neck harness, which mimics the diminished mobility of the cervical spine; bands around the elbows, wrists, and knees to simulate stiffness; boots with foam padding to produce a loss of tactile feedback; and special gloves to “reduce tactile acuity while adding resistance to finger movements.”

Slowly pulling on the aging suit and then standing up—it looks a bit like one of the spacesuits that the Russian cosmonauts wore—you’re at first conscious merely of a little extra weight, a little loss of feeling, a small encumbrance or two at the extremities. Soon, though, it’s actively infuriating. The suit bends you. It slows you. You come to realize what makes it a powerful instrument of emotional empathy: every small task becomes effortful. “Reach up to the top shelf and pick up that mug,” ...requires more attention than you expected. You reach for the mug instead of just getting it. Your emotional cast, as focussed task piles on focussed task, becomes one of annoyance; you acquire the same set-mouthed, unhappy, watchful look you see on certain elderly people on the subway. The concentration that each act requires disrupts the flow of life, which you suddenly become aware is the happiness of life, the ceaseless flow of simple action and responses, choices all made simultaneously and mostly without effort. Happiness is absorption, and absorption is the opposite of willful attention.

The AgeLab is designed to alleviate this progression. It exists to encourage and incubate new technologies and products and services for an ever-larger market of aging people....the AgeLab swiftly discovered that engineering and promoting new products and services specially designed for the expanding market of the aged is a good way of going out of business. Old people will not buy anything that reminds them that they are old. They are a market that cannot be marketed to. In effect, to accept help in getting out of the suit is to accept that we’re in the suit for life. We would rather suffer because we’re old than accept that we’re old and suffer less.

The AgeLab has rediscovered the eternal truth that identity matters to us far more than utility. The most effective way of comforting the aged, the researchers there find, is through a kind of comical convergence of products designed by and supposedly for impatient millennials, which secretly better suit the needs of irascible boomers. The best hearing aids look the most like earbuds. The most effective PERS (personal-emergency-response system) device is an iPhone or an Apple Watch app.

It’s the failure of industry and engineering to address the actual problems of aging—the problems summed up by the aggravations of the agnes suit—that makes Coughlin impatient with scientific speculations about extending life. “We’ve already extended life! What we need is not to put off death a little longer but to write a new narrative of aging as it could be.”

The second section of the article describes several approaches that contest the classic explanation of why we age:

Once we have passed reproductive age, the genes can get sloppy about copying, allowing mutations to accumulate, because natural selection no longer cares. And so things fall apart. The second law of thermodynamics gets us all in the end. The car or the Cuisinart works for a decade, breaks down, and can’t be fixed; rust never sleeps, and we do.

Contra this view:

...in certain genetic labs at Harvard, the chairs and seals and exaptated services of the AgeLab are regarded as mere Band-Aids on the problem to be solved. Here, there are whispers of undying yeast, tales of eternally young mice, rumors of rejuvenated dogs, and scientists who stubbornly insist that age is an illness to be treated like any other...Perhaps aging is not a condition to be managed but a mistake to be fixed.

However,

To pass from the Harvard rejuvenators to the laboratory of Patrick Hof, at the Icahn School of Medicine at Mount Sinai, in Manhattan, is to sober up a little. Here, there is talk not of imminent innovation but of discouragingly minute work proceeding on many slow-moving fronts over decades. Where the Harvard crowd see quick fixes in the near future, Hof, an expert on the neuronal underpinnings of aging and Alzheimer’s, sees the exposure of ever more confounding complexity.

In conclusion...

As you take off the agnes suit—piece by piece; the boots and then the wrist weights and the impeding gloves—the feeling is disconcerting. It’s the return of flow, the feeling of choice and possibility as you begin to move again through the world, that makes you recall that what it is to be young is not to be in a state of ecstasy but merely to be unimpeded, to be in the world without having undue consciousness of your own muscle and bone within it. It’s the same thing we experience when we remove a splinter from our foot; what we get is not happiness in a positive sense but a return to not having to think about the prison and the fact of our flesh. We forget our insides, and fold ourselves back out.

The true condition of youth is the physical ability to forget ourselves. A friend who is still creative in his eighties points out what he calls the geriatric possessive: people past eighty, he says, are expected to say, “I’m going to take my bath,” “I’m going to take my walk.” We can counterpoise that to the pediatric possessive: “You’re going to take your bath,” “It’s time for your nap.” Only in midlife do we feel secure enough to enumerate actions as existing individually outside our possession of them: “I’m going to take a bath,” “I’m going to take a nap.” A bath and a nap exist, briefly, outside our possession of them—they’re just around for the taking, we suppose, and always will be.

We may indeed already be converging as a population — irascible millennials who feel dated at twenty-five and determinedly upbeat boomers who insist on feeling young at seventy — on a single American age, a kind of shared perpetual middleness, where we will dye our hair and take our pills and suddenly collapse in the midst of the dance. Right now, we live well, and then we don’t live well, and then we die. The most that science seems to offer us is this: We’ll live well, and then we’ll die.

With the rise of Trump, the fall of racial prejudice?

Stanley-Becker points to a fascinating study by Hopkins and Washington. Their abstract:

In his campaign and first few years in office, Donald Trump consistently defied contemporary norms by using explicit, negative rhetoric targeting ethnic/racial minorities. Did this rhetoric lead white Americans to express more prejudiced views of African Americans or Hispanics, whether through the normalization of prejudice or other mechanisms? We assess that question using a 13-wave panel conducted with a population-based sample of Americans between 2008 and 2018. We find that via most measures, white Americans' expressed anti-Black and anti-Hispanic prejudice declined after the 2016 campaign and election, and we can rule out even small increases in the expression of prejudice. These results suggest the limits of racially charged rhetoric's capacity to heighten prejudice among white Americans overall. They also indicate that prejudice can behave like an issue attitude: rather than being a fixed predisposition, prejudice can respond thermostatically to changing presidential rhetoric and policy positions.

Stanley-Becker quotes Hopkins:

...it’s quite conceivable that Trump has simultaneously galvanized a small number of highly prejudiced white Americans while also pushing millions more to affirm that they are not as prejudiced.

Hopkins said his discovery is not out of step with other assessments. In fact, his conclusions are in line with recent scholarship suggesting that bias, both implicit and explicit, has declined when it comes to race and sexual orientation, though prejudice has remained steady regarding people with disabilities and actually increased regarding obesity.

The recent scholarship Hopkins references is work from Banaji's group:

Using 4.4 million tests of implicit and explicit attitudes measured continuously from an Internet population of U.S. respondents over 13 years, we conducted the first comparative analysis using time-series models to examine patterns of long-term change in six social-group attitudes: sexual orientation, race, skin tone, age, disability, and body weight. Even within just a decade, all explicit responses showed change toward attitude neutrality. Parallel implicit responses also showed change toward neutrality for sexual orientation, race, and skin-tone attitudes but revealed stability over time for age and disability attitudes and change away from neutrality for body-weight attitudes. These data provide previously unavailable evidence for long-term implicit attitude change and stability across multiple social groups; the data can be used to generate and test theoretical predictions as well as construct forecasts of future attitudes.

Blame the liberals for unlivable cities!

An excellent article by Farhad Manjoo, focusing on San Francisco's affordable housing crisis. Some clips:

Just look at San Francisco, Nancy Pelosi’s city. One of every 11,600 residents is a billionaire, and the annual household income necessary to buy a median-priced home now tops $320,000. Yet the streets there are a plague of garbage and needles and feces, and every morning brings fresh horror stories from a “Black Mirror” hellscape: Homeless veterans are surviving on an economy of trash from billionaires’ mansions. Wealthy homeowners are crowdfunding a legal effort arguing that a proposed homeless shelter is an environmental hazard.

And there is no end in sight to such crushing success. At every level of government, our representatives, nearly all of them Democrats, prove inadequate and unresponsive to the challenges at hand. Witness last week’s embarrassment, when California lawmakers used a sketchy parliamentary maneuver to knife Senate Bill 50, an ambitious effort to undo restrictive local zoning rules and increase the supply of housing.

It was another chapter in a dismal saga of Nimbyist urban mismanagement that is crushing American cities. Not-in-my-backyardism is a bipartisan sentiment, but because the largest American cities are populated and run by Democrats — many in states under complete Democratic control — this sort of nakedly exclusionary urban restrictionism is a particular shame of the left.

Democrats on the 2020 presidential trail rarely mention their ideas for housing affordability, an issue eating American cities alive.

What Republicans want to do with I.C.E. and border walls, wealthy progressive Democrats are doing with zoning and Nimbyism. Preserving “local character,” maintaining “local control,” keeping housing scarce and inaccessible — the goals of both sides are really the same: to keep people out.

Educating liberals about white privilege doesn't make them more empathetic.

Cooley et al. find that people with socially liberal views on the major political issues are actually less likely to empathize with a poor white person’s plight after being given a reading on white privilege (see also the article by Jilani that points to this work):

White privilege lessons are sometimes used to increase awareness of racism. However, little research has investigated the consequences of these lessons. Across 2 studies (N = 1,189), we hypothesized that White privilege lessons may both highlight structural privilege based on race, and simultaneously decrease sympathy for other challenges some White people endure (e.g., poverty)—especially among social liberals who may be particularly receptive to structural explanations of inequality. Indeed, both studies revealed that while social liberals were overall more sympathetic to poor people than social conservatives, reading about White privilege decreased their sympathy for a poor White (vs. Black) person. Moreover, these shifts in sympathy were associated with greater punishment/blame and fewer external attributions for a poor White person’s plight. We conclude that, among social liberals, White privilege lessons may increase beliefs that poor White people have failed to take advantage of their racial privilege—leading to negative social evaluations.

Benefits of a period of exercise persist after 10 years.

Gretchen Reynolds points to a study by Johnson et al. showing long term effects of an experiment conducted from 1998 to 2003, in which overweight volunteers between 40 and 60 were divided into control (inactive), moderate walking), and vigorous (jogging) exercise groups that completed three sessions of their assigned workout each week for eight months. Health markers (aerobic fitness, blood pressure, insulin sensitivity and waist circumference) improved in the exercise but not the control groups. Experimenters were able to get in touch with many subjects 10 years later and found:

Most of the men and women from the control group, who had not exercised 10 years before, had larger waistlines now, while the exercisers displayed little if any middle-aged spread compared to their decade-earlier selves.

Those from the control group also were less fit now. Most had lost about 10 percent of their aerobic capacity, which is typical of the declines seen after about age 40, when most of us will lose about 1 percent of our fitness annually.

But those men and women who had exercised vigorously for eight months during the original experiment retained substantially more fitness. On average, their aerobic capacity had fallen by only about 5 percent, compared to when they had joined the Strride study, and those few who reported still exercising at least four times a week were more fit now than they had been a decade before.

Interestingly, those earlier experimental volunteers who had walked — meaning their exercise had been moderate, not intense — did not seem to have enjoyed the same lasting fitness benefits as those who had exercised more vigorously. Most of them had shed about 10 percent of their aerobic capacity during the past decade, much like the controls.

On the other hand, they showed surprisingly persistent improvements in their metabolic health, more so than among the intense exercisers. The walkers from 10 years ago still had healthier blood pressures and insulin sensitivity than they had had before joining the earlier experiment, even if they rarely exercised now. They had also had relatively healthier metabolisms than the men and women who had exercised intensely all those years before.

A Sunday Afternoon Musicale - Bridges and Mendelssohn

This post falls in the 'random curious stuff' of the MindBlog title above. I want to share some of my current musical efforts with MindBlog readers. When MindBlog began in 2016 I started to share with readers some of the videos made at Sunday afternoon musical/social events at my 1860 schoolhouse/residence in Madison Wisconsin. I'm now living full time in Austin Texas, and have been fortunate to be able form a piano trio with two accomplished musicians, violinist Andrea Gore and Cellist Karen Foster Cason. Andrea hosted a Musicale this past Sunday at her beautiful home built on the banks of a creek running into Lake Travis. The pictures show our trio, and the natural grotto photographed from the deck of the house. I embed a rehearsal video of the Mendelssohn Allegro and give links to rehearsal videos of the rest of the program (I wish I had recorded the coherence and precision of the event itself). The Mendelssohn Allegro and Finale are the most pyrotechnical of the offerings.

Program for the Sunday, May 19, 1:00 Musicale at Awalt

Frank Bridge (1879-1941)
Miniatures for Violin, Violoncello, & Piano
4. Romance
5. Intermezzo
6. Saltarello

Felix Mendelssohn (1809-1847) Piano Trio No. 2 in D minor, Op. 66
1. Allegro energico e con fuoco
2. Andante espressivo
3. Scherzo: Molto allegro quasi presto
4. Finale: Allegro appassionato

Andrea Gore, Violin
Karen Foster Cason, Cello
Deric Bownds, Piano

Are rich people really less generous than poor people?

Here is a ‘fact’ (that rich people are less generous than poor people) that I had locked into mind that turns out to be wrong. They are not less generous, contra the findings of an often cited 2015 landmark study. From Schmukle et al.:

Significance

Are the rich less generous than the poor? Results of studies on this topic have been inconsistent. Recent research that has received widespread academic and media attention has provided evidence that higher income individuals are less generous than poorer individuals only if they reside in a US state with comparatively large economic inequality. However, in large representative datasets from the United States (study 1), Germany (study 2), and 30 countries (study 3), we did not find any evidence for such an effect. Instead, our results suggest that the rich are not less generous than the poor, even when economic inequality is large. This result has implications for contemporary debates on what increasing inequality in resource distributions means for modern societies.

Abstract

A landmark study published in PNAS [Côté S, House J, Willer R (2015) Proc Natl Acad Sci USA 112:15838–15843] showed that higher income individuals are less generous than poorer individuals only if they reside in a US state with comparatively large economic inequality. This finding might serve to reconcile inconsistent findings on the effect of social class on generosity by highlighting the moderating role of economic inequality. On the basis of the importance of replicating a major finding before readily accepting it as evidence, we analyzed the effect of the interaction between income and inequality on generosity in three large representative datasets. We analyzed the donating behavior of 27,714 US households (study 1), the generosity of 1,334 German individuals in an economic game (study 2), and volunteering to participate in charitable activities in 30,985 participants from 30 countries (study 3). We found no evidence for the postulated moderation effect in any study. This result is especially remarkable because (i) our samples were very large, leading to high power to detect effects that exist, and (ii) the cross-country analysis employed in study 3 led to much greater variability in economic inequality. These findings indicate that the moderation effect might be rather specific and cannot be easily generalized. Consequently, economic inequality might not be a plausible explanation for the heterogeneous results on the effect of social class on prosociality.

Like the emperor’s new clothes, DNA kits are a tailored illusion

I recommend reading this article by George Estreich. Here are a few clips:

Most people remember the emperor: a vain ruler, swindled into paying for a nonexistent magical garment, parades in public, only to be embarrassed by a little boy. To me, the story is really about the swindling tailors. Audacious, imaginative, their true product is a persuasive illusion, one keyed to the vulnerabilities of their target audience. In contemporary terms, the story is about marketing; and as such, the tale is tailor-made for an examination of genetic ancestry tests, because these too are sold with expert persuasion, with promises woven from our hopes, our fears, and the golden thread of DNA.

With these new tests, as in Hans Christian Andersen’s 19th-century tale, a gap yawns between the promise and the reality – and now and then, as in the story, someone says so in the public square. For example, when Phil Rogers, a reporter in Chicago, tried out home DNA test kits from competing companies last year, he discovered contradictory results. So did the Canadian reporter Charlsie Agro and her twin sister Carly, who mailed spit samples to 23andMe, FamilyTreeDNA, AncestryDNA, MyHeritage and LivingDNA. As with Rogers, the companies gave different histories – Balkan ancestry, for example, ranged from 14 to 61 per cent – but 23andMe actually reported different scores for each twin. (According to the company, Charlsie has French and German ancestors, while Carly does not.)

The tests are sold with variations on a single pitch: find your story. The companies don’t mention that the story might shade into fiction, or that stories can conflict. The evolutionary geneticist Mark Thomas at University College London has dismissed ancestry testing as ‘genetic astrology’, but it could be as useful to think of it as genetic gossip: a rumoured past that, like most rumours, is at least partly true.

Chasing his dreams of status and power, the emperor misses the swindle: the ‘weavers’ make off with tangible wealth, while the emperor receives nothing. The entire performance is a masterful misdirection, a distraction from the truth of the exchange. In the same way, the promises of discovering identity and the genealogical past are a misdirection: the real exchange takes place offstage, with drug companies and others paying for access to the data that customers actually pay to give. Once it’s given, customers are vulnerable to future data breaches (and you can’t, at this date at least, change your genome), and they aren’t guaranteed compensation for any profits the data might lead to.

Father's physical activity directly enhances offspring's brain physiology and cognition.

Experiments on mice suggest that human kids of athletic fathers might have more smarts than kids of couch potatoes. From McGreevy et al.:

Significance

Physical exercise is well known for its positive effects on general health (specifically, on brain function and health), and some mediating mechanisms are also known. A few reports have addressed intergenerational inheritance of some of these positive effects from exercised mothers or fathers to the progeny, but with scarce results in cognition. We report here the inheritance of moderate exercise-induced paternal traits in offspring’s cognition, neurogenesis, and enhanced mitochondrial activity. These changes were accompanied by specific gene expression changes, including gene sets regulated by microRNAs, as potential mediating mechanisms. We have also demonstrated a direct transmission of the exercise-induced effects through the fathers’ sperm, thus showing that paternal physical activity is a direct factor driving offspring’s brain physiology and cognitive behavior.

Abstract

Physical exercise has positive effects on cognition, but very little is known about the inheritance of these effects to sedentary offspring and the mechanisms involved. Here, we use a patrilineal design in mice to test the transmission of effects from the same father (before or after training) and from different fathers to compare sedentary- and runner-father progenies. Behavioral, stereological, and whole-genome sequence analyses reveal that paternal cognition improvement is inherited by the offspring, along with increased adult neurogenesis, greater mitochondrial citrate synthase activity, and modulation of the adult hippocampal gene expression profile. These results demonstrate the inheritance of exercise-induced cognition enhancement through the germline, pointing to paternal physical activity as a direct factor driving offspring’s brain physiology and cognitive behavior.

Ready to pounce - Cat smarts get some attention

I live in a symbiotic relationship with my two Abyssinian cats, and so was gratified, given that canine social cognition is the subject of dozens of scientific papers, to see that feline cognition is beginning to get more attention. One simple reason for the difference is that dogs want to please humans and cooperate with experimenters, while cats could generally care less, and after a few trials will walk away from earnest efforts to engage their responses. When a human points at something, a chimp will not react, but a dog, like a human toddler, knows to look at the same thing. Turns out that cats do the same thing, they will trot over to a bowl that a human points to. It is turning out that cats match dogs in many tests of social smarts. Alas, I'm going to show you a cat video... not of some adorable feline faux pas, but of behavioral work being done with cats:



And, since I'm showing cat pictures, I can't resist introducing you to Abyssinians Marvin and Melvin, shown napping while I'm driving between Madison WI and Austin TX.

Want to escape your liberal bubble? Try this.....

I have a recommendation for MindBlog readers like myself who are concerned about their immersion in the liberal bubble of the New York Times, Washington Post and the numerous sarcastic evening show commentators (Colbert, Maher, Maddow, Noah, etc.). The media (alas, like scientific reality in general!) does indeed have a liberal bias. I'm now finding a crystallized antithesis to my bubble in the American Greatness website, whose daily email screeds I have subscribed to after reading an Op-Ed piece in the NY Times by its publisher and editor Chris Buskirk. To note only three of the twelve pieces in last Thursday's email: Democrats’ Collapse Could Happen Quickly , Yes,Christians Can Support Trump Without Risk to Their Witness , and  Why the Left Mocks the Bible . A clip from the last of these, a telling piece:

...on virtually every important value in life, the left and the Bible are diametrically opposed...

The biblical view is that people are not basically good. Evil, therefore, comes from within human nature. For the left, human nature is not the source of evil. Capitalism, patriarchy, poverty, religion, nationalism or some other external cause is the source of evil.

The biblical view is that nature was created for man. The left-wing view is that man is just another part of nature.

The biblical view is that man is created in the image of God and, therefore, formed with a transcendent, immaterial soul. The left-wing view—indeed, the view of all secular ideologies—is that man is purely material, another assemblage of stellar dust.

Relevant to humans being 'born in sin' I hope to do a post soon on a book I just finished, Nicholas Christakis' Magnum Opus “Blueprint: The Evolutionary Origins of a Good Society”. This book, like Pinker's "Enlightenment Now" , the subject of previous MindBlog posts, paints a more benign picture of desirable human traits that have evolved to make society possible.

MindBlog Changes

I want to explain to readers who check MindBlog daily why the drumbeat of a post each weekday (4,700 posts over the past 13 years) has stopped. My 78th year starts next week, and performative professor Deric has decided to spend more time doing other things, to try a few new tricks. I will continue to occasionally post on interesting material I encounter.

The Case for Doing Nothing

An article by Olga Mecking fits so well with my increasing allergic reaction to making myself busy all the time that I have to pass on a few edited and rearranged clips:

Perhaps it’s time to stop all this busyness. Being busy...is rarely the status indicator we’ve come to believe it is...There’s a way out...and it’s not more mindfulness, exercise or a healthy diet... What we’re talking about is … doing nothing. Or, as the Dutch call it, niksen...being like a car whose engine is running but isn’t going anywhere...coming to a moment with no plan other than just to be.

...the idea of niksen is to take conscious, considered time and energy to do activities like gazing out of a window or sitting motionless...permission granted to spend the afternoon just hanging out...daydreaming and idleness let the mind search for its own stimulation...counterintuitively, idleness can be a great productivity tool..it takes you out of your mind, and then you see things clearly after a while...it makes us more creative, better at problem-solving, better at coming up with creative ideas......For that to happen, though, total idleness is required.

...don’t get discouraged if you don’t catch on immediately to the benefits of idleness...like beginning a new workout routine: At first, you might get sore, but after a while, you’ll find yourself in this moment of "Oh, this feels fantastic.” Keep your devices out of reach so that they’ll be more difficult to access, and turn your home into a niksen-friendly area. Add a soft couch, a comfy armchair, a few cushions or just a blanket. Orient furniture around a window or fireplace rather than a TV.

Same-sex marriage legalization reduced implicit and explicit antigay bias

Interesting work from Ofosu et al. shows how government legislation can inform individuals’ attitudes, even when these attitudes may be deeply entrenched and socially and politically volatile.:

The current research tested whether the passing of government legislation, signaling the prevailing attitudes of the local majority, was associated with changes in citizens’ attitudes. Specifically, with ∼1 million responses over a 12-y window, we tested whether state-by-state same-sex marriage legislation was associated with decreases in antigay implicit and explicit bias. Results across five operationalizations consistently provide support for this possibility. Both implicit and explicit bias were decreasing before same-sex marriage legalization, but decreased at a sharper rate following legalization. Moderating this effect was whether states passed legislation locally. Although states passing legislation experienced a greater decrease in bias following legislation, states that never passed legislation demonstrated increased antigay bias following federal legalization. Our work highlights how government legislation can inform individuals’ attitudes, even when these attitudes may be deeply entrenched and socially and politically volatile.

Why are some people more anxious than others? Brain correlates of trait anxiety.

Why does trait anxiety (the stable tendency to attend to, experience, and report negative emotions such as fears, worries, and anxiety across many situations) vary between individuals? Berry et al. have measured self-reported trait anxiety in healthy adults, examining its relationships with brain dopamine function (Most anxiolytic drugs target serotonergic and GABAergic neurotransmitter systems) and also examining functional connectivity within circuits implicated in anxiety regulation. This enabled them to probe the neural substrates of individual differences.

  Significance Statement

It is common wisdom that individuals vary in their baseline levels of anxiety. We all have a friend or colleague we know to be more “tightly wound” than others, or, perhaps, we are the ones marveling at others' ability to “just go with the flow.” Although such observations about individual differences within nonclinical populations are commonplace, the neural mechanisms underlying normal variation in trait anxiety have not been established. Using multimodal brain imaging in humans, this study takes initial steps in linking intrinsic measures of neuromodulator release and functional connectivity within regions implicated in anxiety disorders. Our findings suggest that in healthy adults, higher levels of trait anxiety may arise, at least in part, from reduced dopamine neurotransmission.

Abstract

Trait anxiety has been associated with altered activity within corticolimbic pathways connecting the amygdala and rostral anterior cingulate cortex (rACC), which receive rich dopaminergic input. Though the popular culture uses the term “chemical imbalance” to describe the pathophysiology of psychiatric conditions such as anxiety disorders, we know little about how individual differences in human dopamine neurochemistry are related to variation in anxiety and activity within corticolimbic circuits. We addressed this issue by examining interindividual variability in dopamine release at rest using [¹¹C]raclopride positron emission tomography (PET), functional connectivity between amygdala and rACC using resting-state functional magnetic resonance imaging (fMRI), and trait anxiety measures in healthy adult male and female humans. To measure endogenous dopamine release, we collected two [¹¹C]raclopride PET scans per participant. We contrasted baseline [¹¹C]raclopride D2/3 receptor binding and D2/3 receptor binding following oral methylphenidate administration. Methylphenidate blocks the dopamine transporter, which increases extracellular dopamine and leads to reduced [¹¹C]raclopride D2/3 receptor binding via competitive displacement. We found that individuals with higher dopamine release in the amygdala and rACC self-reported lower trait anxiety. Lower trait anxiety was also associated with reduced rACC–amygdala functional connectivity at baseline. Further, functional connectivity showed a modest negative relationship with dopamine release such that reduced rACC–amygdala functional connectivity was accompanied by higher levels of dopamine release in these regions. Together, these findings contribute to hypodopaminergic models of anxiety and support the utility of combining fMRI and PET measures of neurochemical function to advance our understanding of basic affective processes in humans.

[11C]

Is Superintelligence Impossible?

Andy Clarke does an interesting and concise commentary on a discussion between Daniel Dennett and David Chalmers. I pass on the final two paragraphs of Clark's comments and suggest you read the whole piece.

I think we can divide the space of possible AI minds into two reasonably distinct categories. One category comprises the “passive AI minds” that seemed to be the main focus of the Chalmers-Dennett exchange. These are driven by large data sets and optimize their performance relative to some externally imposed choice of “objective function” that specifies what we want them to do—win at GO, or improve paperclip manufacture. And Dennett and Chalmers are right—we do indeed need to be very careful about what we ask them to do, and about how much power they have to implement their own solutions to these pre-set puzzles.

The other category comprises active AIs with broad brush-strokes imperatives. These include Karl Friston’s Active Inference machines. AI’s like these spawn their own goals and sub-goals by environmental immersion and selective action. Such artificial agents will pursue epistemic agendas and have an Umwelt of their own. These are the only kind of AIs that may, I believe, end up being conscious of themselves and their worlds—at least in any way remotely recognizable as such to us humans. They are the AIs who could be our friends, or who could (if that blunt general imperative was played out within certain kinds of environment) become genuine enemies. It is these radicalized embodied AIs I would worry about most. At the same time (and for the same reasons) I’d greatly like to see powerful AIs from that second category emerge. For they would be real explorations within the vast space of possible minds.

Digital addiction and the attention economy.

Jia Tolentino's "What It Takes to Put Your Phone Away" is a broad essay on our digital addictions that focuses on two recent books: Cal Newport's “Digital Minimalism: Choosing a Focused Life in a Noisy World” and Jenny Odell's “How to Do Nothing: Resisting the Attention Economy." I strongly recommend that you read it. I am going to resist the impulse to pass on many choice clips of text, limiting myself to two:

Odell elegantly aligns the crisis in our natural world and the crisis in our minds: what has happened to the natural world is happening to us, she contends, and it’s happening on the same soon-to-be-irreparable scale. She sees “little difference between habitat restoration in the traditional sense and restoring habitats for human thought”; both are endangered by “the logic of capitalist productivity.” She believes that, by constantly disclosing our needs and desires to tech companies that sift through our selfhood in search of profit opportunities, we are neglecting, even losing, our mysterious, murky depths—the parts of us that don’t serve an ulterior purpose but exist merely to exist. The “best, most alive parts” of ourselves are being “paved over by a ruthless logic of use.”

On the monetization of attention:

Legislators might succeed in granting citizens more control over the data that they generate by using the Internet, but social-media companies will, presumably, continue to treat their users like little countries that can be strip-mined to make other people rich...We remain attached to these technologies in a way that is clearly affecting the health of the body politic. Newport insists that our Internet-fuelled lack of mental peace and quiet is a better explanation for the current wave of American anxiety than “the latest crisis—be it the recession of 2009 or the contentious election of 2016.”

A bit of digital detox - rehearsing a Mendelssohn Piano Trio

I have been fortunate to find in Austin TX two accomplished string players, violinist Andrea Gore and cellist Karen Foster Cason, who join me in sight reading interesting piano trios. We have decided to work up a few of the pieces we like to do for a house concert in late May, - a musical/social occasion of the sort I used to do in the 1860 stone schoolhouse that was the living room of my Twin Valley Road residence in Madison Wisconsin. I thought I would pass on to MindBlog readers a bit of our rehearsal this past Thursday, working on a Mendelssohn piano trio.

The "digital detox" phrase in this post's title is a clip from Jia Tolentino's recent New Yorker Article "What It Takes to Put Your Phone Away." I'm very much in the mood these days to get away from the "invasion of your cognitive landscape" that it describes and that I have permitted by being open to so many digital input streams as I spend a large fraction of my days hovering over screen and keyboard.

I find that the exercise of playing music is an antidote to this malaise, and I want to spend more time doing it. Don't be surprised if MindBlog posts become less frequent. Anyway, here is the 1st movement of the Mendelssohn Piano Trio No. 2 in C Minor, in a video recording done with my iPhone XS Max with a Shure condenser microphone plugged into its USB port:

Bringing dead brains back to life.

Work by Vrselja et al. on restoring brain function in pigs four hours after death has been extensively covered by the popular press. I want to pass on the abstract to their paper, and then one clip that shows how far away the recovery observed is from actually restoring brain function.

The brains of humans and other mammals are highly vulnerable to interruptions in blood flow and decreases in oxygen levels. Here we describe the restoration and maintenance of microcirculation and molecular and cellular functions of the intact pig brain under ex vivo normothermic conditions up to four hours post-mortem. We have developed an extracorporeal pulsatile-perfusion system and a haemoglobin-based, acellular, non-coagulative, echogenic, and cytoprotective perfusate that promotes recovery from anoxia, reduces reperfusion injury, prevents oedema, and metabolically supports the energy requirements of the brain. With this system, we observed preservation of cytoarchitecture; attenuation of cell death; and restoration of vascular dilatory and glial inflammatory responses, spontaneous synaptic activity, and active cerebral metabolism in the absence of global electrocorticographic activity. These findings demonstrate that under appropriate conditions the isolated, intact large mammalian brain possesses an underappreciated capacity for restoration of microcirculation and molecular and cellular activity after a prolonged post-mortem interval.

This beautiful work shows that the brain has a much greater capacity for restoration that had been realized. The authors were able to obtain intracellular recordings from hippocampus pyramidal cells. However:

Monitoring of electrical activity from the dorsal surface of the brain using clinical-grade surface grid electrodes and electrocorticography (ECoG; also known as intracranial electroencephalography, EEG) revealed that spontaneous global activity did not reemerge and that ECoG activity was isoelectric throughout BEx perfusion. This indicates that the organization and/or summation of synaptic activity of individual neurons was inadequate to elicit detectable network activity as assessed by ECoG.