What we see is biased by ongoing neural activity.

Rassi et al. (open source) show that ongoing neural activity in our brain, as in the fusiform face area, can influence what we perceive in an ambiguous sensory stimulus such as the Rubin face/vase illusion.

Significance

Ongoing neural activity influences stimulus detection—that is, whether or not an object is seen. Here, we uncover how it could influence the content of what is seen. In ambiguous situations, for instance, ongoing neural fluctuations might bias perception toward one or the other interpretation. Indeed, we show increased information flow from category-selective brain regions (here, the fusiform face area [FFA]) to the primary visual cortex before participants subsequently report seeing faces rather than a vase in the Rubin face/vase illusion. Our results identify a neural connectivity pathway that biases future perception and helps determine mental content.

Abstract

Ongoing fluctuations in neural excitability and in networkwide activity patterns before stimulus onset have been proposed to underlie variability in near-threshold stimulus detection paradigms—that is, whether or not an object is perceived. Here, we investigated the impact of prestimulus neural fluctuations on the content of perception—that is, whether one or another object is perceived. We recorded neural activity with magnetoencephalography (MEG) before and while participants briefly viewed an ambiguous image, the Rubin face/vase illusion, and required them to report their perceived interpretation in each trial. Using multivariate pattern analysis, we showed robust decoding of the perceptual report during the poststimulus period. Applying source localization to the classifier weights suggested early recruitment of primary visual cortex (V1) and ∼160-ms recruitment of the category-sensitive fusiform face area (FFA). These poststimulus effects were accompanied by stronger oscillatory power in the gamma frequency band for face vs. vase reports. In prestimulus intervals, we found no differences in oscillatory power between face vs. vase reports in V1 or in FFA, indicating similar levels of neural excitability. Despite this, we found stronger connectivity between V1 and FFA before face reports for low-frequency oscillations. Specifically, the strength of prestimulus feedback connectivity (i.e., Granger causality) from FFA to V1 predicted not only the category of the upcoming percept but also the strength of poststimulus neural activity associated with the percept. Our work shows that prestimulus network states can help shape future processing in category-sensitive brain regions and in this way bias the content of visual experiences.

More diversity in Flow-land.

I will pass on part of an email from Mr. Todd Denen occasioned by my 8/16/19 post, in which he assures me, that unlike the Flow Genome Project and Flow Collective Research Project discussed in that post, his Flow Research University is legit:

“ My name is Todd Denen and I just came across your post on the FGP guys. I just wanted to say not all Flow training programs are bullshit.....

I'm the founder of the Advanced Flow University which teaches the Flow state from the perspective of the Yogi Flow Experts.

In my book, PEAK PERFORMANCE SECRETS, I reveal the Advanced Flow Techniques which have been used by the Yogi Flow Experts for over 5,000 years. This has allowed them to achieve the highest level of Consciousness, the 7th Level of Flow.

If you are interested, I'm doing a promotion on it right now and you can get it for free on Amazon….."

Here is a screen shot showing only three of the numerous free books by Mr. Denen available from Amazon's Kindle offerings.

I couldn't resist downloading and having a look at "Peak Performance Secrets" and "FLOW STATE SEX TEST" (Advanced Flow University Book 3).

Unbelievable stuff.   Kudos to Amazon for its carefully vetted high quality Kindle offerings!

What we see is influenced by what we can do about it

Djebbara et al. do experiments that resolve an ancient debate on the relationship between cognition, movement, and environment, showing that potential actions afforded by an architectural environment influence perception. We perceive the world not as an observer-independent reality but in the mold of potential actions, shaped by the current needs and other personal attributes of the actor–perceiver. I pass on their significance and abstract statements, and then a clip from a description of the work by Gepshtein and Snider.

Significance

Using electroencephalography and virtual reality, our research provides a unique perspective on the centuries-old open-ended debate in cognitive neuroscience and philosophy on the relationship among cognition, movement, and environment. Our results indicate that cortical potentials vary as a function of bodily affordances reflected by the physical environment. First, the results imply that cognition is inherently related to the potential movement of the body; thus, we posit that action is interrelated with perception, actively influencing the perceivable environment. Second, these results indicate that moving in space is to continuously construct a prediction of a world of affordances, suggesting that architects take up the continuity of spaces, given that the unfolding of bodily movement alters perception and experience.

Abstract

Anticipating meaningful actions in the environment is an essential function of the brain. Such predictive mechanisms originate from the motor system and allow for inferring actions from environmental affordances, and the potential to act within a specific environment. Using architecture, we provide a unique perspective on the ongoing debate in cognitive neuroscience and philosophy on whether cognition depends on movement or is decoupled from our physical structure. To investigate cognitive processes associated with architectural affordances, we used a mobile brain/body imaging approach recording brain activity synchronized to head-mounted displays. Participants perceived and acted on virtual transitions ranging from nonpassable to easily passable. We found that early sensory brain activity, on revealing the environment and before actual movement, differed as a function of affordances. In addition, movement through transitions was preceded by a motor-related negative component that also depended on affordances. Our results suggest that potential actions afforded by an environment influence perception.

And, the clip from the review by Gepshtein and Snider:

Djebbara et al. had human participants walking freely while immersed in a virtual environment. A wearable “brain/body imaging setup” included a 64-channel electroencephalographic (EEG) cap that allowed researchers to record the participants’ electrical activity of the brain. The experiment consisted of a series of trials in which participants confronted simulated doors of different widths: Narrow (0.2 m wide), medium (1 m), and wide (1.5 m). At the onset of every trial, the participant was shown 1 of the 3 doors for several seconds. Then the wall framing the door changed its color: To green, prompting the person to pass through the door (the Go condition), or to red, indicating that the person should not approach the door (NoGo). A key result from the analysis of the participants’ brain activity came from the temporal window that just followed the Go/NoGo signal. On average, the part of the brain responsible for processing visual information functioned differently in the Go and NoGo conditions. In the Go condition, brain activity depended significantly on whether the door was passable or not, but in the NoGo condition, no such difference was found.

The authors explain this result by evoking the familiar concept of affordance, introduced by the influential American psychologist James J. Gibson in 1966. Gibson coined the term “affordance” to designate action opportunities offered by objects, trying to find a substitute to the term “value” which he worried would carry “an old burden of philosophical meaning”

A Schism in Flow-land? Flow Genome Project vs. Flow Research Collective

In Nov. 2017 I did a scathing review of  the "Stealing Fire" book by Jamie Wheal and Steven Kotler - in support of expensive workshops offered by their "Flow Genome Project" - purporting to show the latest science relevant to the flow states of enhanced human performance described in Mihaly Csikszentmihalyi’s original writings on this subject. I judged the book a mess, with very little of substance to offer. A follow up post in Sept. 2018 passed on an exchange between one dissatisfied customer and a representative of the flow genome workshops.

Given this background, I can't resist passing on to MindBlog readers an email I just received indicating that there has been trouble in Flow-land... Mr. Kotler and Mr. Wheal have apparently split up and are now present competing websites, both very slick, with Mr. Kotler's (https://www.flowresearchcollective.com) radiating a bit more gravitas than Mr. Wheal's (https://www.flowgenomeproject.com.) Here is the email:

Hey there, 

I work with Steven Kotler who is featured in this article on your site. I have a critical request to change the text and link from Flow Genome Project to Flow Research Collective as this is Steven's new company. 

Currently there is traffic that is being directed from your site to the old company that Steven resigned from and so it's important that we get this updated so that the piece is accurate and up to date. 

We are not requesting that the mention of Flow Genome Project must be withdrawn in relation to Jamie, just that we need it to be clear that Steven is with the Flow Research Collective and that we're directing toward's [sic] that site. 

Please confirm that this is possible. Thanks, 

Gabby-- Gabby Nuñez Chief Of Customer Service and Satisfaction 

W: flowresearchcollective.com

Continuing in the tradition of the "Stealing Fire" book the link in the email "this article on your site" is not to either of the posts I mention above (Nov. 2017, Sept. 2018), but to all the posts done in Nov. and Dec.  of 2017.

I'm not taking the time to look further into this, but would suggest that any potential clients of these expensive purportedly transformational programs do due diligence. CAVEAT EMPTOR!

How weight training changes the brain.

Gretchen Reynolds points to work by Kelty et al. showing that weight training in rats can ameliorate mild cognitive impairment in rats induced by a injecting a lipopolysaccharide known to induce inflammation in the brain, creating a rodent form of mild cognitive impairment or early dementia. The weight training also induces chemical factors that support new nerve cell growth. How do you get rats to train with weights? Get them to climb a ladder for a Froot Loop reward with weights gently taped to their rear ends! Do three workouts a week, increasing the load as in regular resistance training. Similar experiments (inducing mild cognitive impairment) obviously can't be done in humans, but it would be useful to look more at whether and how much weight training in humans might stimulate the appearance of nerve growth factors that support new nerve cell growth. Numerous studies have shown that aerobic exercise has this effect.

Five myths about consciousness

In a perspective piece for the Washington Post Christof Koch (chief scientist and president of the Allen Institute of Brain Science) does a brief and concise debunking of five common fables about consciousness. I suggest you give it a read. The myths are:

Humans have a unique brain.

Science will never understand consciousness.

Dreams contain hidden clues about our secret desires.

We are susceptible to subliminal messages.

Near-death 'visions' are evidence of life after death.

It’s not just how the game is played, it’s whether you win or lose

An open source article from Molina et al.:

Growing disparities of income and wealth have prompted extensive survey research to measure the effects on public beliefs about the causes and fairness of economic inequality. However, observational data confound responses to unequal outcomes with highly correlated inequality of opportunity. This study uses a novel experiment to disentangle the effects of unequal outcomes and unequal opportunities on cognitive, normative, and affective responses. Participants were randomly assigned to positions with unequal opportunities for success. Results showed that both winners and losers were less likely to view the outcomes as fair or attributable to skill as the level of redistribution increased, but this effect of redistribution was stronger for winners. Moreover, winners were generally more likely to believe that the game was fair, even when the playing field was most heavily tilted in their favor. In short, it’s not just how the game is played, it’s also whether you win or lose.

Ingroup vigilance in collectivistic cultures

Fascinating work from Liu et al., who provide a more nuanced view of how people in more collectivist cultures are more suspicious of possible unethical intentions in others than people in more individualistic cultures.

Significance

Decades of research have described East Asian cultures as collectivistic, often characterized by ingroup relationships that are harmonious and cooperative. We find evidence that people in collectivistic cultures can also be more vigilant, mindful of ingroup members’ bad intentions. Participants imagined what coworkers and classmates would do in competition. Compared with individualistic Americans, people in China expected more unethical competition. Is this a “China phenomenon” or a phenomenon of collectivistic culture? We next compared regional cultures within China to rule out between-country alternative explanations. We found that people from China’s collectivistic rice-farming regions were more vigilant than people from the individualistic wheat-farming regions. This research suggests a more balanced view of collectivism, revealing tensions that can co-occur with harmony.

Abstract

Collectivistic cultures have been characterized as having harmonious, cooperative ingroup relationships. However, we find evidence that people in collectivistic cultures are more vigilant toward ingroup members, mindful of their possible unethical intentions. Study 1 found that Chinese participants were more vigilant than Americans in within-group competitions, anticipating more unethical behaviors from their peers. Study 2 replicated this finding by comparing areas within China, finding that people from China’s collectivistic rice-farming regions exhibit greater ingroup vigilance than people from the less collectivistic wheat-farming regions. The rice/wheat difference was mediated by greater perceived within-group competition. Study 3 found that Chinese participants were more likely than Americans to interpret a peer’s friendly behavior as sabotage in disguise. We also manipulated within-group competition and found that it increased ingroup vigilance in both cultures. Finally, study 3 identified two boundary conditions where cultural differences in ingroup vigilance decrease: an unambiguously competitive win–lose situation where Americans also exhibit vigilance, and an unambiguously cooperative win–win situation where Chinese participants relax their vigilance. This research contributes to a more balanced view of collectivism, revealing its interpersonal tensions in the forms of within-group competition and ingroup vigilance.

Feeling pleasure from music - brain correlates of why people differ

From Martínez-Molina et al.:

SIGNIFICANCE

Music is one of the most important sources of pleasure for many people, but at the same time there are important individual differences in the sensitivity to musical reward. Previous studies have revealed the critical involvement of the functional connectivity between perceptual and subcortical brain areas in the enjoyment of music. However, it is unknown whether individual differences in music sensitivity might arise from variability in the structural connectivity among these areas. Here we show that structural connectivity between supratemporal and orbitofrontal cortices, and between orbitofrontal and nucleus accumbens, predict individual differences in sensibility to music reward. These results provide evidence for the critical involvement of the interaction between the subcortical reward system and higher-order cortical areas in music-induced pleasure.

Abstract

People show considerable variability in the degree of pleasure they experience from music. These individual differences in music reward sensitivity are driven by variability in functional connectivity between the nucleus accumbens (NAcc), a key structure of the reward system, and the right superior temporal gyrus (STG). However, it is unknown whether a neuroanatomical basis exists for this variability. We used diffusion tensor imaging and probabilistic tractography to study the relationship between music reward sensitivity and white matter microstructure connecting these two regions via the orbitofrontal cortex (OFC) in 38 healthy human participants (24 females and 14 males). We found that right axial diffusivity (AD) in the STG–OFC connectivity inversely correlated with music reward sensitivity. Additionally, right mean diffusivity and left AD in the NAcc-OFC tract also showed an inverse correlation. Further, AD in this tract also correlated with previously acquired BOLD activity during music listening, but not for a control monetary reward task in the NAcc. Finally, we used mediation analysis to show that AD in the NAcc–OFC tract explains the influence of NAcc activation during a music task on music reward sensitivity. Overall, our results provide further support for the idea that the exchange of information among perceptual, integrative, and reward systems is important for musical pleasure, and that individual differences in the structure of the relevant anatomical connectivity influences the degree to which people are able to derive such pleasure.

Can an uprising of decency win the next presidential election?

I want to point to this massively cogent piece by David Brooks, and also pass on a video done by the democratic presidential candidate he mentions, Marianne Williamson. He credits her with being the only candidate who most effectively cuts to the real heart of what is at issue in the next presidential election: who we are as a people, our national character, and the moral atmosphere in which we raise our children.

It is no accident that the Democratic candidate with the best grasp of this election is the one running a spiritual crusade, not an economic redistribution effort. Many of her ideas are wackadoodle, but Marianne Williamson is right about this: “This is part of the dark underbelly of American society: the racism, the bigotry and the entire conversation that we’re having here tonight. If you think any of this wonkiness is going to deal with this dark psychic force of the collectivized hatred that this president is bringing up in this country, then I’m afraid that the Democrats are going to see some very dark days.”

And she is right about this: “We’ve never dealt with a figure like this in American history before. This man, our president, is not just a politician; he’s a phenomenon. And an insider political game will not be able to defeat it. … The only thing that will defeat him is if we have a phenomenon of equal force, and that phenomenon is a moral uprising of the American people.”

They are unready for it, but it falls on the Democrats to rebuild the moral infrastructure of our country. That does not mean standing up and saying, “Donald Trump is a racist!” 500 times a day. It means reminding Americans of the values we still share, and the damage done when people are not held accountable for trampling on them. The values are pretty basic and can be simply expressed:

Unity: We’re one people. Our leader represents all the people. He doesn’t go around attacking whole cities and regions.

Honesty: We can’t have deliberative democracy without respect for the truth. None of us want congenital liars in our homes or our workplaces.

Pluralism: Human difference makes life richer and more interesting. We treasure members of all races and faiths for what they bring to the mosaic.

Sympathy: We want to be around people with good hearts, who feel for those who are suffering, who are faithful friends, whose daily lives are marked by kindness.

Opportunity: We want all children to have an open field and a fair chance in the great race of life.

Trump has put himself on the wrong side of all these values. So Democrats, go ahead and promote your plans. But also lead an uprising of decency. There must be one Democrat who, in word and deed, can do that.

Here is the Williamson video:

What can we do when facts don't matter?

Some of Trump’s most ardent supporters are those whose lives are most diminished and compromised by his actions. They do not let facts cloud their beliefs. A similar situation is seen in the anti-science denial of the scientifically proven benefits of vaccinations or genetically modified foods. The Dunning Kruger effect is in force. Those who know the least think they are experts. As Carroll points out in his NYTimes opinion piece, only subtle persuasion can be used to nudge those who are immune to factual knowledge. Some clips:

In a paper published early this year in Nature Human Behavior, scientists asked 500 Americans what they thought about foods that contained genetically modified organisms.

The vast majority, more than 90 percent, opposed their use. This belief is in conflict with the consensus of scientists. Almost 90 percent of them believe G.M.O.s are safe — and can be of great benefit.

The second finding of the study was more eye-opening. Those who were most opposed to genetically modified foods believed they were the most knowledgeable about this issue, yet scored the lowest on actual tests of scientific knowledge.

Carroll points out that...

A great deal of science communication still relies on the “knowledge deficit model,” an idea that the lack of support for good policies, and good science, merely reflects a lack of scientific information.

The problem is that experts have been giving accurate information for years to little effect.

In 2016, a number of researchers argued in an essay that those in the sciences needed to realize that the public may not process information in the same way they do. Scientists need to be formally trained in communication skills, they said, and they also need to realize that the knowledge deficit model makes for easy policy, but not necessarily good results.

It seems important to engage the public more, and earn their trust through continued, more personal interaction, using many different platforms and technologies. Dropping knowledge from on high — which is still the modus operandi for most scientists — doesn’t work.

Politics are in our DNA - why societies evolved to have both conservatives and liberals.

Sebastian Junger points out an evolutionary rationale for the presence of both liberals and conservatives within a group - that over our evolutionary history such heterogeneity has proven to enhance a group's ability to compete with other groups. One could wish that respect for these deep roots of our current political polarization might ameliorate the culture of contempt that currently prevails between red and blue America. There are now numerous studies correlating conservative or liberal orientation with basic biological differences, notably studies on young adults showing correlations between political orientation, brain structures, and genetics. Such differences can be shaped by different socialization processes (such as strict versus nurturant family values). Yudkin reviews differences in core beliefs (on how dangerous the world is, on personal responsibility, on parenting philosophy, etc.) between conservatives and liberals to suggest that the sides are more aligned on many issues than they realize.

Here is a clip from Junger's article:

If liberalism and conservatism are partly rooted in genetics, then those worldviews had to have been adaptive — and necessary — in our evolutionary past. That means that neither political party can accuse the other of being illegitimate or inherently immoral; we are the way we are for good reason. Every human society must do two things: It must be strong enough to protect itself from outside groups, and it must be fair enough to avoid internal conflict. A society entirely composed of liberals risks being overrun by enemies, and a society entirely composed of conservatives risks breaking apart over issues of inequality — “social justice,” as it’s now termed.

Put those groups together, however, and you have addressed the two greatest threats to human welfare: enemies and discord. The task for every society, from the earliest Homo sapiens of Africa to Americans of the 21st century, is to accommodate different values and worldviews into one ethos. It’s not easy to do, but our own genetic diversity clearly demonstrates that it’s possible. Otherwise, one set of values would have gradually dominated the other until there was no political discord at all, just a broad, flat uniformity. That may sound appealing at the moment. But in the long term, what a great loss that would be.

Re-skilling the brain.

For the first time, Oby et al (open source, nice graphics) observe the new neural activity patterns that cause a new learned behavior.

Significance

Consider a skill you would like to learn, like playing the piano. How do you progress from “Chopsticks” to Chopin? As you learn to do something new with your hands, does the brain also do something new? We found that monkeys learned new skilled behavior by generating new neural activity patterns. We used a brain–computer interface (BCI), which directly links neural activity to movement of a computer cursor, to encourage animals to generate new neural activity patterns. Over several days, the animals began to exhibit new patterns of neural activity that enabled them to control the BCI cursor. This suggests that learning to play the piano and other skills might also involve the generation of new neural activity patterns.

Abstract

Learning has been associated with changes in the brain at every level of organization. However, it remains difficult to establish a causal link between specific changes in the brain and new behavioral abilities. We establish that new neural activity patterns emerge with learning. We demonstrate that these new neural activity patterns cause the new behavior. Thus, the formation of new patterns of neural population activity can underlie the learning of new skills.

Deindividuation of outgroup faces occurs at the earliest stages of visual perception.

From Hughes et al:

A hallmark of intergroup biases is the tendency to individuate members of one’s own group but process members of other groups categorically. While the consequences of these biases for stereotyping and discrimination are well-documented, their early perceptual underpinnings remain less understood. Here, we investigated the neural mechanisms of this effect by testing whether high-level visual cortex is differentially tuned in its sensitivity to variation in own-race versus other-race faces. Using a functional MRI adaptation paradigm, we measured White participants’ habituation to blocks of White and Black faces that parametrically varied in their groupwise similarity. Participants showed a greater tendency to individuate own-race faces in perception, showing both greater release from adaptation to unique identities and increased sensitivity in the adaptation response to physical difference among faces. These group differences emerge in the tuning of early face-selective cortex and mirror behavioral differences in the memory and perception of own- versus other-race faces. Our results suggest that biases for other-race faces emerge at some of the earliest stages of sensory perception.

Facial muscles in dogs evolved for interactions with humans.

From Kaminski et al. (check out the videos in the article):

Domestication shaped wolves into dogs and transformed both their behavior and their anatomy. Here we show that, in only 33,000 y, domestication transformed the facial muscle anatomy of dogs specifically for facial communication with humans. Based on dissections of dog and wolf heads, we show that the levator anguli oculi medialis, a muscle responsible for raising the inner eyebrow intensely, is uniformly present in dogs but not in wolves. Behavioral data, collected from dogs and wolves, show that dogs produce the eyebrow movement significantly more often and with higher intensity than wolves do, with highest-intensity movements produced exclusively by dogs. Interestingly, this movement increases paedomorphism and resembles an expression that humans produce when sad, so its production in dogs may trigger a nurturing response in humans. We hypothesize that dogs with expressive eyebrows had a selection advantage and that “puppy dog eyes” are the result of selection based on humans’ preferences.

Around the globe, financial temptation increases civic honesty.

Shalvi does a commentary on work by Cohn et al. Here is the Cohn et al. abstract:

Civic honesty is essential to social capital and economic development but is often in conflict with material self-interest. We examine the trade-off between honesty and self-interest using field experiments in 355 cities spanning 40 countries around the globe. In these experiments, we turned in more than 17,000 lost wallets containing varying amounts of money at public and private institutions and measured whether recipients contacted the owners to return the wallets. In virtually all countries, citizens were more likely to return wallets that contained more money. Neither nonexperts nor professional economists were able to predict this result. Additional data suggest that our main findings can be explained by a combination of altruistic concerns and an aversion to viewing oneself as a thief, both of which increase with the material benefits of dishonesty.

It’s never simple...The tidy textbook story about the primary visual cortex is wrong.

When I was a postdoc in the Harvard Neurobiology department in the mid-1960’s I used to have afternoon tea with the Hubel and Weisel group. These are the guys who got a Nobel prize for, among other things, finding that the primary visual cortex is organized into cortical columns of cells that responded to lines that prefer different orientations. Another grouping of columns, called ‘blobs’ responded selectively to color and brightness but not orientation. These two different kinds of groups sent their outputs to higher visual areas that were supposed to integrate the information. My neurobiology course lectures and my Biology of Mind book showed drawings illustrating these tidy distinctions.

Sigh… now Garg et al. come along with two-photon calcium imaging to probe a very large spatial and chromatic visual stimulus space and map functional microarchitecture of thousands of neurons with single-cell resolution. They show that processing of orientation and color is combined at the earliest stages of visual processing, totally challenging the existing model. Their abstract:

Previous studies support the textbook model that shape and color are extracted by distinct neurons in primate primary visual cortex (V1). However, rigorous testing of this model requires sampling a larger stimulus space than previously possible. We used stable GCaMP6f expression and two-photon calcium imaging to probe a very large spatial and chromatic visual stimulus space and map functional microarchitecture of thousands of neurons with single-cell resolution. Notable proportions of V1 neurons strongly preferred equiluminant color over achromatic stimuli and were also orientation selective, indicating that orientation and color in V1 are mutually processed by overlapping circuits. Single neurons could precisely and unambiguously code for both color and orientation. Further analyses revealed systematic spatial relationships between color tuning, orientation selectivity, and cytochrome oxidase histology.

An anti-aging pill with some credibility....

An AARP article points to studies on the new drug RTB101, which boosts immune function in older people and lowers risk for respiratory diseases. By virtue of it's inhibition of the multiprotein complex TORC1, which mediates temporal control of cell growth, it is also a potential anti-aging drug. Below is text from the anti-aging website lifespan.io:

resTORbio, Inc. is developing RTB101, an oral medication that inhibits target of rapamycin complex 1 (TORC1). Using a combination of RTB101 and everolimus, another TORC1 inhibitor, the company is testing a comprehensive immunotherapy program to fight respiratory tract infections in the elderly, improving the immune system rather than attempting to target individual infectious agents.

The mammalian target of rapamycin (mTOR) pathway uses the multiprotein complexes TORC1 and TORC2 to conduct signaling. While inhibiting TORC2 has been observed to decrease lifespan, TORC1 inhibition has been shown to have multiple positive effects, including enhanced brain functions, reduction of adipose tissue, and delaying the onset of age-related pathology. Inhibiting TORC1 with both RTB101 and everolimus decreases S6K while increasing 4EBP1 and Atg; affecting each of these downstream products in this way is reported to enhance lifespan.

In 2018, the company reported that a phase 2b trial of RTB101 has returned positive results for boosting the immune system to respond better to respiratory infections. The trial saw 652 aged people with increased risk of RTIs enroll and compared to the control group, there were significantly fewer patients treated with RTB101 who suffered from one or more RTIs during a 16-week trial period. The next step for resTORbio is to conduct a study of its effects on other infections, heart failure, or autophagy-related diseases later in 2018.

Concluding the successful Phase 2 and 2b studies the company has agreed with the FDA to proceed to a large scale phase 3 clinical trial scheduled to begin later in 2019...resTORbio has licensed the worldwide rights for its product from Novartis Limited, a major pharmaceutical company...Website: resTORbio

Correlating our our physical and mental experiences of stress linked to psychological and physical well-being

Davidson and colleagues at the Univ. of Wisconsin show that individual differences in the ability to associate subjective stress and heart rate are related to psychological and physical well being. Here is a description of the work from a newsletter, followed by the abstract from Psychological Sciences. They:

...analyzed data from 1,065 participants in the Midlife in the United States (MIDUS) study, a longitudinal effort looking at well-being as adults age. Participants completed a series of stressful computer tasks, including a mental math task and a color identification task.

Before, during and after the tasks, researchers measured participants’ heart rate and asked them to rate their stress on a scale of one to 10 throughout the study.

After the participants completed the stress tests, researchers compared each person’s heart rate to the stress levels they reported — a measure called “stress-heart rate coherence”— and found that some people’s stress levels aligned with their heart rate better than others.

To examine the link between stress-heart rate coherence and people’s emotional well-being, researchers used psychological questionnaires focused on well-being, depression, anxiety and coping as well as blood samples measuring inflammation markers. Researchers found that people with greater stress-heart rate coherence had fewer symptoms of anxiety and depression, greater overall psychological well-being and lower levels of inflammation.

Here is the journal article's abstract:

The physiological response to stress is intertwined with, but distinct from, the subjective feeling of stress, although both systems must work in concert to enable adaptive responses. We investigated 1,065 participants from the Midlife in the United States 2 study who completed a self-report battery and a stress-induction procedure while physiological and self-report measures of stress were recorded. Individual differences in the association between heart rate and self-reported stress were analyzed in relation to measures that reflect psychological well-being (self-report measures of well-being, anxiety, depression), denial coping, and physical well-being (proinflammatory biomarkers interleukin-6 and C-reactive protein). The within-participants association between heart rate and self-reported stress was significantly related to higher psychological well-being, fewer depressive symptoms, lower trait anxiety, less use of denial coping, and lower levels of proinflammatory biomarkers. Our results highlight the importance of studying individual differences in coherence between physiological measures and subjective mental states in relation to well-being.

And here is a PDF of the article.

The Problem With ‘Sharenting’

An article in the NYTimes 'Privacy Project' by Kamenetz resonates with my own experience of very mixed reactions to viewing some of what I consider the most private and intimate details of the lives of my 5 and 7 year old grandsons occasionally revealed in some of the Facebook posts by their parents. I feel embarrassed for the boys, and sometimes how they would feel in their 20s and 30s if they were to look back at these posts on their childhood. (A pre-facebook version of the situation from my childhood is a photograph of two legs - five year old Deric - protruding from under a newspaper sitting on the toilet...how cute!). Some clips from the Kamenetz piece:

Today, many children’s social media presence starts with a sonogram, posted, obviously, without consent. One study from Britain found that nearly 1,500 images of the average child had been placed online by their fifth birthday. Parents get a lot of gratification from telling kids’ stories online...It’s less clear what our children have to gain from their lives being broadcast in this way. ..parents’ rights to free speech and self-expression are at odds with children’s rights to privacy when they are young and vulnerable...This is especially true when the information is potentially damaging. Imagine a child who has behavior problems, learning disabilities or chronic illness. Mom or Dad understandably want to discuss these struggles and reach out for support. But those posts live on the internet, with potential to be discovered by college admissions officers and future employers, friends and romantic prospects. A child’s life story is written for him before he has a chance to tell it himself.

Even if you confine your posts about your children to sunny days and birthday parties, any information you provide about them — names, dates of birth, geographic location — could be acquired by data brokersClose X, companies that collect personal information and sell it to advertisers.

Finally, there’s display and commodification. In 2018, the top earner on YouTube, according to Forbes, was a 7-year-old boy who brought in $22 million by playing with toys. It’s never seemed more accessible to become famous at a wee age, and the type of children who used to sing into a hairbrush in the mirror are often clamoring to start their own channels today.

The most egregious abuses are just the tip of the iceberg, though. For every moneymaking influencer, there are millions of less-successful stage parents and wannabes scratching for followers on YouTube and Instagram. They’re out there shoving cameras in children’s faces, using up their free time, killing spontaneity, warping the everyday rituals of childhood into long working shoots.

When it comes to childhood and technology, we adults are the horror show.

Looking for a dose of optimism?

I want to point to a recent NYTimes Op-Ed piece by David Brooks that is a bit more upbeat than his frequent hand wringing over the dissolution of old verities. A few clips from its later paragraphs:

The reality and challenge is that America has become radically pluralistic. We used to be unipolar — one dominant majority culture and a lot of minority groups that defined themselves against it. Now we’re multipolar. We’re all minorities now.

That could blow us to smithereens. But who knows? We could learn to be minorities together, to be what Rabbi Jonathan Sacks calls creative minorities. In a brilliant 2013 lecture, Sacks noted that when Solomon’s temple was destroyed and the Jews were cast into exile, the prophet Jeremiah had a surprising message: Go to new lands. Build houses. Plant gardens. Seek the peace and prosperity of the cities in which you settle.

In a world of radical pluralism, we are all Jews. We have no choice but to build a mass multicultural democracy, a society that has no dominant center but is a collection of creative minorities...Nearly 200 years ago, Tocqueville wrote that democracy was creating a new sort of man. Pluralism today is creating a new sort of person, especially among the young. They don’t just relish diversity; they embody it. Many have mixed roots — say, half-French/half-Dominican. Many are border stalkers; they live between cultures, switch back and forth, and work hard to build a multiplicity of influences into a single coherent life. They’re Whitmanesque, containing multitudes, holding opposite ideas in their minds at the same time.

Radical pluralism also necessitates retelling the nation’s history. We’ve always been a universal nation, a crossroads nation, a nation whose very identity is defined by the fact that it is a hub for a dense network of minorities and subgroups, and the distinct way of life they fashion to interact and flourish together.

I used to think that America had to find a new unifying national narrative. Now I wonder if not having a single national narrative will become our national narrative.

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