Another list - "Keys to happiness"

The New York Times has done a simple list of pointers to basic articles and research on well being. I'm passing on a few of the items from a condensed version of that list, rearranging the list in almost reverse order to reflect not importance, but items that seem to me to be less commonly acted on. So, keys of happiness:

Don't obsess about it, and don't overdo it.

If all else fails, fake it.

Gratitude helps.

Make friends, family, and weekends a priority

Be healthy

A succinct list of some of our common psychological errors.

I want to point to Belsky's article on why we think we are better decision makers under uncertainty than we really are. He summarizes several common errors:

The sunk cost fallacy - hanging on to a decision, or an investment, in an unconscious desire to justify it.

Loss aversion - reacting more strongly to loss of a resource (time, goods, or money) than to a similar gain.

Overconfidence - overrating our abilities, knowledge, and skill (two thirds of investors rate their financial sophistication as advanced, but barely pass a financial literacy exam.)

Optimism bias - which seems to be hard-wired into our brains because it has evolutionarily useful, driving humans to strive in the face of long odds.

Hindsight bias - rewriting history to make ourselves look good, as in misremembering our forecasts in a way that makes us look smarter.

Attribution bias - attributing good outcomes to our own skills, but bad outcomes to causes over which we had no control.

Confirmation bias - giving too much weight to information that supports our existing beliefs and discounting that which does not.

Muscle mass and nerve control enhanced in octogenarian athletes.

Power et al. expand their earlier studies on active runners ~65 years old to find ~14% greater muscle mass and ~28% more functioning motor nerve units in octogenarian masters athletes than in healthy age-matched controls.

Our group has shown a greater number of functioning motor units (MU) in a cohort of highly-active older(~65y) masters runners relative to age-matched controls. Owing to the precipitous loss in the number of functioning MUs in the 8th and 9th decade of life it is unknown whether older world class octogenarian masters athletes (MA) would also have greater numbers of functioning MUs (MUNE) compared with age-matched controls. We measured MU numbers and neuromuscular transmission stability in the tibialis anterior of world champion MAs (~80y), and compared the values to healthy age-matched controls (~80y). Decomposition-enhanced spike-triggered averaging was used to collect surface and intramuscular electromyography signals during dorsiflexion at ~25% of maximum voluntary isometric contraction(MVC). Near fibre (NF) MU potential analysis was used to assess neuromuscular transmission stability. For the MAs as compared with age-matched controls; the amount of excitable muscle mass (CMAP) was 14% greater (p less than 0.05), there was a trend (p=0.07) towards a 27% smaller surface detected motor unit potential - representative of less collateral reinnervation, and 28% more functioning MUs (p less than 0.05). Additionally, the MAs had greater MU neuromuscular stability than the controls as indicated by lower NF jitter and jiggle values (p less than 0.05). These results demonstrate that high performing octogenarians better maintain neuromuscular stability of the MU and mitigate the loss of MUs associated with aging well into the later decades of life during which time the loss of muscle mass and strength become functionally relevant. Future studies need to identify the concomitant roles genetics and exercise play in neuroprotection.

Why sad music can make us feel good.

As an update to a previous MindBlog post on why we like sad music, I want to note Ojiaku's brief mention of several articles on this subject.

Sad music might make people feel vicarious unpleasant emotions, found a study published last year in Frontiers in Psychology. But this experience can ultimately be pleasurable because it allows a negative emotion to exist indirectly, and at a safe distance. Instead of feeling the depths of despair, people can feel nostalgia for a time when they were in a similar emotional state: a non-threatening way to remember a sadness.

People who are very empathetic are more likely to take pleasure in the emotional experience of sad music, according to another study in Frontiers of Psychology. Others enjoy sad songs because they help them return to an emotionally balanced state, according to a review in Frontiers in Human Neuroscience, published in 2015. And those more open to varied experiences might enjoy the songs because the unique emotions that come up when listening to the music fulfill their need for novelty in thoughts and feelings.

From the Frontiers in Neurosciences abstract:

We offer a framework to account for how listening to sad music can lead to positive feelings, contending that this effect hinges on correcting an ongoing homeostatic imbalance. Sadness evoked by music is found pleasurable: (1) when it is perceived as non-threatening; (2) when it is aesthetically pleasing; and (3) when it produces psychological benefits such as mood regulation, and empathic feelings, caused, for example, by recollection of and reflection on past events.

The Social Gene

I want to pass on some clips from Joseph's Swift's review of a book, "The Society of Genes" by Yanai and Lercher that updates Richard Dawkins's classic "The Selfish Gene" publised 40 years ago. (Their title reminds me of "Society of Mind," a classic book published in 1986 by Marvin Minsky, who recently died at age 88.)

Genetic research has moved rapidly since the publication of Richard Dawkins's The Selfish Gene 40 years ago. In the intervening years, we have come to realize that many of the most interesting and important phenomena in human biology are not caused by any single gene. Processes like the immune system's ability to recognize infection, or the timing of our sleep-wake cycle, for example, are the product of many genes working together in a highly integrated way. Citing a wealth of recent research that explores the ways genes work together to produce complex biological processes, Itai Yanai and Martin Lercher argue that it is time to embrace a new, more holistic, metaphor in their book, The Society of Genes.

Rather than focus on any one gene, Yanai and Lercher invite the reader to step back and observe how genes assemble together to make a global genetic system, or genome. From here, one can see that the labor within the genome is not divided equally. Whereas many genes encode for proteins that perform a single monotonous task, such as breaking down a certain type of sugar or producing a specific skin pigment, there are others that serve such fundamental roles that their removal would lead to the crumbling of the genomic society altogether. Among the latter group are genes that manage the behavior of a host of other genes.

When genes are mismanaged by their masters, organisms can be transformed in dramatic ways. For example, in humans, when SOX9 fails to direct its wide range of subordinates succinctly, sex reversal and skeletal malformations can occur.

Given that catastrophic things tend to happen when genes don't work together properly, changes to how the genomic society is run are a rare occurrence. When genes with new abilities evolve, Darwinian selection determines whether they will join the ranks as productive members of society. Our ancestors obtained genes that could interpret light as color and a gene for a more efficient oxygen-carrying hemoglobin in this very way.

And then there are the genes that don't contribute to society at all. Instead, they secure their position by hijacking the system. The LINE1 gene, for example, encodes only for its own dispersal, copying and pasting itself throughout our genome while providing the society with no clear benefit. The “bad behavior” of genes amounts to scandal in the genomic society, and learning about their exploits is one of the most enjoyable elements of reading the book.

There are even genes that work to ensure the survival of individual cells within an organism by wreaking havoc on others. In fruit flies, for example, a pair of genes involved in sperm production work in concert to produce both a poison and its antidote. The toxic compound is released from the cell, while the antidote is retained. In this way, surrounding sperm cells without the gene pair are killed. On reading about such systems, one begins to realize that it's not quite right to imagine our genome as some idealized republic. This is a society that is easily compromised from within its own ranks.

In the years since The Selfish Gene was published, the human genome has been sequenced, along with the genomes of many other species. Indeed, probing one's own genes is beginning to become routine. Thus, The Society of Genes represents a timely and welcome handbook for navigating this postgenomic era.

Pterostilbene anti-aging supplement - undesirable side effects

In a January 15 MindBlog post, I noted the start of my most recent foray into supplements meant to have salutary effects on energy, mind, body, longevity, etc., giving some references to work on pterostilbene, a resveratrol cousin whose added methyl groups allow more rapid absorption after ingestion and slow down its removal by the liver. I’m wanting to report now on my experience of trying Elysium’s pills containing 125 mg pterostilbene and 25 mg nicotinamide riboside, (one per day, instead of the two recommended). I emphasize that this is a single report, people doubtless vary in their sensitivity.

I used the half dose because my previous 2008 experiment with resveratrol was terminated after 19 days because of increasing arthritic symptoms, especially in hands, which disappeared with a week after stopping the supplement. The MindBlog post reporting this result received 33 comments noting side effects of arthritic symptoms, foot and finger soreness and stiffness, sleep disturbance, joint pain, etc. All of these effects are consistent with possible immune system activation and inflammation. 

On starting one pill a day, I thought I noticed after a few days a subtle increase in body energy, a slightly more benign and positive temperament (there are a few reports of anxiolytic effects of low doses of pterostilbene), and most interesting to me, a decrease in rumination or mind wandering versus focused attention . By day 30 increasing stiffness in fingers and body movement was obvious. I terminated the pills, and stiffness disappeared over the next few days. After seven days off, I started one pill a day again. After four days, stiffness and arthritic symptoms had clearly increased in my hands. On stopping the pills again, stiffness disappeared over the next few days.

So, I guess that’s it for me on the resveratrol or pterostilbene trip. Pity… chemical studies noting their desirable effects are quite compelling. I do think Elysium and other vendors of these products should state their possible side effects.

Are we all sexists and racists?

I want to point to Miller's review of work of Levanon et al., as well as other studies, showing that that when women have moved into occupations in large numbers, those jobs have begun paying less even after controlling for education, work experience, skills, race and geography.

A striking example is to be found in the field of recreation — working in parks or leading camps — which went from predominantly male to female from 1950 to 2000. Median hourly wages in this field declined 57 percentage points, accounting for the change in the value of the dollar, according to a complex formula used by Professor Levanon. The job of ticket agent also went from mainly male to female during this period, and wages dropped 43 percentage points...The same thing happened when women in large numbers became designers (wages fell 34 percentage points), housekeepers (wages fell 21 percentage points) and biologists (wages fell 18 percentage points). The reverse was true when a job attracted more men. Computer programming, for instance, used to be a relatively menial role done by women. But when male programmers began to outnumber female ones, the job began paying more and gained prestige.

In the vein of work described in a previous MindBlog post, an excellent article by Ojiaku, a former Neuroscience Graduate Student at the University of Wisconsin, gives extensive references to work demonstrating that our unconscious racism starts early, and creates a deadly empathy gap. The studies Ojiaku cites:

...showed racially biased differences in cognitive and emotion-related brain regions, including the anterior cingulate cortex (ACC). One of the ACC’s functions is registering when you experience your own pain or empathy for another person’s pain. In the study, Chinese and Caucasian college students were shown video clips of both Chinese and Caucasian faces either in pain or not in pain as scientists conducted brain scans. The researchers measured increased ACC activity in the brains of those viewing painful expressions on the faces belonging to their own race, but decreased ACC activity when viewing pain in another race, uncovering a racially biased difference in empathetic response to pain in the brain.

Another study:

...asked participants to view video images of white, black, and violet-illuminated (for racially neutral) hands being pricked with a needle. While watching the prick, the volunteers were tested for their empathetic response via transcranial magnetic stimulation (TMS); the greater the reaction to the stimulation, the higher the empathetic response to the pain...Interestingly enough, both black and white participants had an adequately empathetic response to seeing the violet hand being pricked. However, all of the participants – both black and white – failed to react as strongly to the pain of someone who was outside their racial group. The study also found that people who scored higher in racial bias on the IAT (implicit association test) – meaning that they showed more implicit preferences for faces belonging to their own race – also showed less reactivity to pain experienced by someone from another race.

The last straw:

...is a study from the University of Iowa published in Psychological Science in February 2016. Incredibly, the researchers found that when white test subjects were primed with photos of five-year-old black boys, they were far more likely to mistake objects such as toys for guns – or even to claim to see guns when there were none. In sharp contrast, when subjects were primed with photos of five-year-old white boys before seeing the objects, the effect reserved, as they were more likely to mistake guns for toys. These findings are ominous for black children, because it shows that youth does not mitigate their potential to become targets of racist events, as in the case of the 12-year-old Tamir Rice, a young black boy carrying a toy ‘BB gun’ in a park in Cleveland, Ohio, whom the police shot in less than two seconds after arriving on the scene.

Another social science, Economics, looks at itself.

Mindblog recently noted a large study that tested the replicability of studies in psychology journals. Only 36% of the findings were repeated. The quality of results has also been questioned in many fields such as medicine, neuroscience, and genetics. Camerer et al. have now tested the replicability of experiments published in top-tier economics journals, finding that two-thirds of the 18 studies examined yielded replicable estimates of effect size and direction. Their abstract:

The replicability of some scientific findings has recently been called into question. To contribute data about replicability in economics, we replicated 18 studies published in the American Economic Review and the Quarterly Journal of Economics between 2011 and 2014. All of these replications followed predefined analysis plans that were made publicly available beforehand, and they all have a statistical power of at least 90% to detect the original effect size at the 5% significance level. We found a significant effect in the same direction as in the original study for 11 replications (61%); on average, the replicated effect size is 66% of the original. The replicability rate varies between 67% and 78% for four additional replicability indicators, including a prediction market measure of peer beliefs.

Overkill in techno-aids for 'Mens Sana in Corpore Sano'

None of us would argue with the 'sound mind in a sound body' injunction from Juvenal’s Latin satires (~100 AD), a goal that can be accomplished by diligent pursuit of a few simple activities. Two NYTimes articles note how modern technology manages, for a profit, to vastly encumber that pursuit.

With regard to 'sound mind,' Gelles notes:

The other morning, I woke up and brewed a cup of Mindful Lotus tea ($6 for 20 bags). On the subway, I loaded the Headspace app on my iPhone and followed a guided mindfulness exercise ($13 a month for premium content). Later in the day, I dropped by Mndfl, a meditation studio in Greenwich Village ($20 for a 30-minute class)...There are more than two dozen mindfulness apps for smartphones, some offering $400 lifetime subscriptions. The Great Courses has two mindfulness packages, each with a couple of dozen DVDs for $250. For an enterprising contemplative, it’s never been easier to make a buck...On a recent trip to Whole Foods, near the kombucha, I came across a new product from the health food maker Earth Balance: a dairy-free mayonnaise substitute called Mindful Mayo ($4.50 a jar). Then, in line, I picked up a copy of Mindful magazine ($6)....With so many mindful goods and services for sale, it can be easy to forget that mindfulness is a quality of being, not a piece of merchandise

...with so many cashing in on the meditation craze, it’s hard not to wonder whether something essential is being lost...Increasingly, mindfulness is being packaged as a one-minute reprieve, an interlude between checking Instagram and starting the next episode of “House of Cards.” One company proclaims it has found the “minimum effective dose” of meditation that will change your life. On Amazon, you can pick up “One-Minute Mindfulness: 50 Simple Ways to Find Peace, Clarity, and New Possibilities in a Stressed-Out World.” Dubious courses promise to help people “master mindfulness” in a few weeks.

More often than not, however, the people I know who take time to meditate — carefully observing thoughts, emotions and sensations — are sincere in their aspirations to become less stressed, more accepting and at least a little happier.

Hutchinson discusses the greater than billion dollar market for body fitness aids (which are not used by more than half their buyers six months after their purchase) suggesting:

...a more fundamental question about our rapid adoption of wearable fitness tech: Is the data we collect with these devices actually useful?...Last September, in The British Journal of Sports Medicine, Australian researchers published a review of studies that compared subjective and objective measures of “athlete well-being” during training. The objective measures included state-of-the-art monitoring of heart rate, blood, hormones and more; the subjective measure boiled down to asking the athletes how they felt. The results were striking: The researchers found that as the athletes worked out, their own perception registered changes in training stress with “superior sensitivity and consistency” to the high tech measures...running with a GPS watch “slackens the bond between perception and action.” In other words, when you’re running, instead of speeding up or slowing down based on immediate and intuitive feedback from your body and environment, you’re inserting an unwieldy extra cognitive step that relies on checking your device as you go.

On the positive side:

Health researchers also want to use your tracked data to figure out what works in the real world to improve health and fitness, rather than testing theories in the artificial conditions of the lab. An analysis of in-the-wild data from 4.2 million MyFitnessPal users, for example, recently yielded unexpected insights into the habits of successful weight-losers compared with unsuccessful ones: They ate nearly a third more fiber, and 11 percent less meat. And the dietary changes the successful dieters made between 2014 and 2015 bucked broader trends: They consumed more grains, cereal and raw fruit, but fewer eggs.

As prosaic as it sounds, this is the greatest promise of the wearables revolution. Once the novelty of tracking your exercise habits wears off, knowing how many steps you took today or what your resting heart rate was yesterday soon loses its interest. But together, 100 million of us wearing wristbands could uncover some truly valuable insights into what works to make us healthier and fitter.

Perhaps the most effective and simple way to increase aerobic fitness: use a jump rope!

Storing long term emotional memories.

A Journal of Neuroscience precis of an article by Cambiaghi et al., slightly edited:

When we remember events, we often also remember what we were feeling at the time. Cambiaghi et al. asked where in the brain we store such connections. To answer this, they conditioned rats to associate a tone with an unpleasant experience. They then simultaneously recorded from two brain regions, the higher-order auditory cortex and the amygdala, 1 day and 1 month after the conditioning. Animals displayed fearful behavior at both time points, and both areas showed learning-evoked changes. However, the two brain regions only interacted significantly after 1 month had passed (The cue increased the synchrony of their firing.) The degree of interaction predicted the animals' ability to recognize the tone as unpleasant.

Screenagers - brain executive function immediately diminished by television

An article by Jolly points to interesting work by Lillard and Peterson. Their summary:

The goal of this research was to study whether a fast-paced television show immediately influences preschool-aged children's executive function (eg, self-regulation, working memory).  Sixty 4-year-olds were randomly assigned to watch a fast-paced television cartoon or an educational cartoon or draw for 9 minutes. They were then given 4 tasks tapping executive function, including the classic delay-of-gratification and Tower of Hanoi tasks. Parents completed surveys regarding television viewing and child's attention. Children who watched the fast-paced television cartoon performed significantly worse on the executive function tasks than children in the other 2 groups when controlling for child attention, age, and television exposure.  Just 9 minutes of viewing a fast-paced television cartoon had immediate negative effects on 4-year-olds' executive function. Parents should be aware that fast-paced television shows could at least temporarily impair young children's executive function.

Our progression towards a nation of rich and poor

A fascinating and foreboding piece by Rank and Hirschl describe their development of a "economic risk calculator' available at riskcalculator.org

The idea behind our approach is similar to the idea behind a doctor’s ability to predict your risk of heart disease. Using several pieces of information (blood pressure, cholesterol, etc.), your doctor can make a reasonable estimate of your chances of having a heart attack in the next 10 years. These numbers are based on statistical patterns derived from a very large sample of families that make up the Framingham Heart Study, the longitudinal study of cardiovascular health that began in 1948.

Our predictions of economic risk work in a similar way. Using hundreds of thousands of case records taken from a longitudinal study of Americans that began in 1968, we estimate the likelihood — based on factors like race, education, marital status and age — of an individual’s falling below the official poverty line during the next five, 10 or 15 years. (The poverty line for a family of four in 2015 was approximately $24,000.)

Take someone ... who is in his or her later 30s, white, not married, with an education beyond high school. It turns out that the 15-year risk of poverty for such a person is actually 32 percent. In other words, one-third of such individuals will experience at least one year below the poverty line in the not-so-distant future...between the ages of 20 and 75, nearly 60 percent of Americans will spend at least one year below the official poverty line, and three-quarters will experience a year below 150 percent of the poverty line.

We are in danger of becoming an economically polarized society in which a small percentage of the population is free from economic risk, while a vast majority of Americans will encounter poverty as a normal part of life.

Suppressing memory of trauma causes forgetting of other memories.

An interesting article from Hulbert et.al. on how suppressing memory of a trauma also causes forgetting of unrelated experiences in the period surrounding the trauma.:

Hippocampal damage profoundly disrupts the ability to store new memories of life events. Amnesic windows might also occur in healthy people due to disturbed hippocampal function arising during mental processes that systemically reduce hippocampal activity. Intentionally suppressing memory retrieval (retrieval stopping) reduces hippocampal activity via control mechanisms mediated by the lateral prefrontal cortex. Here we show that when people suppress retrieval given a reminder of an unwanted memory, they are considerably more likely to forget unrelated experiences from periods surrounding suppression. This amnesic shadow follows a dose-response function, becomes more pronounced after practice suppressing retrieval, exhibits characteristics indicating disturbed hippocampal function, and is predicted by reduced hippocampal activity. These findings indicate that stopping retrieval engages a suppression mechanism that broadly compromises hippocampal processes and that hippocampal stabilization processes can be interrupted strategically. Cognitively triggered amnesia constitutes an unrecognized forgetting process that may account for otherwise unexplained memory lapses following trauma.

Vasopressin increases human risky cooperative behavior

From Brunnlieb et al.:

Significance

Most forms of cooperative behavior take place in a mutually beneficial context where cooperation is risky as its success depends on unknown actions of others. In two pharmacological experiments, we show that intranasal administration of arginine vasopressin (AVP), a hormone that regulates mammalian social behaviors such as monogamy and aggression, increases humans’ tendency to engage in mutually beneficial cooperation. Several control tasks ruled out that AVP’s effects were driven by increased willingness to bare risks in the absence of social context, beliefs about the actions of one’s partner, or altruistic concerns. Our findings provide novel causal evidence for a biological factor underlying cooperation and are in accord with previous findings that cooperation is intrinsically rewarding for humans.

Abstract

The history of humankind is an epic of cooperation, which is ubiquitous across societies and increasing in scale. Much human cooperation occurs where it is risky to cooperate for mutual benefit because successful cooperation depends on a sufficient level of cooperation by others. Here we show that arginine vasopressin (AVP), a neuropeptide that mediates complex mammalian social behaviors such as pair bonding, social recognition and aggression causally increases humans’ willingness to engage in risky, mutually beneficial cooperation. In two double-blind experiments, male participants received either AVP or placebo intranasally and made decisions with financial consequences in the “Stag hunt” cooperation game. AVP increases humans’ willingness to cooperate. That increase is not due to an increase in the general willingness to bear risks or to altruistically help others. Using functional brain imaging, we show that, when subjects make the risky Stag choice, AVP down-regulates the BOLD signal in the left dorsolateral prefrontal cortex (dlPFC), a risk-integration region, and increases the left dlPFC functional connectivity with the ventral pallidum, an AVP receptor-rich region previously associated with AVP-mediated social reward processing in mammals. These findings show a previously unidentified causal role for AVP in social approach behavior in humans, as established by animal research.

Pictures of green spaces make you happier.

Reynolds points to work by van den Berg et al. showing that viewing pictures of green versus built urban areas enhances parasympathetic nervous system activity that is calming and restorative. This results are consonant with those obtained by a Stanford study on the effects of a brief nature experience on rumination, and also with discussions of "blue mind" (cf. calming effect of blue water) versus "red mind."

This laboratory study explored buffering and recovery effects of viewing urban green and built spaces on autonomic nervous system activity. Forty-six students viewed photos of green and built spaces immediately following, and preceding acute stress induction. Simultaneously recorded electrocardiogram and impedance cardiogram signal was used to derive respiratory sinus arrhythmia (RSA) and pre-ejection period (PEP), indicators of respectively parasympathetic and sympathetic activity. The findings provide support for greater recovery after viewing green scenes, as marked by a stronger increase in RSA as a marker of parasympathetic activity. There were no indications for greater recovery after viewing green scenes in PEP as a marker of sympathetic activity, and there were also no indications of greater buffering effects of green space in neither RSA nor PEP. Overall, our findings are consistent with a predominant role of the parasympathetic nervous system in restorative effects of viewing green space.

Rachmaninoff Morceaux de fantasie Op. 3, No. 4, Polichinelle

This is the last of the pieces from my recent recitals that I want to pass on to readers - a robust beginning for a Monday morning!

Anxiety suppresses prefrontal cortex decision ability.

Interesting work from Park et al.:

A debilitating aspect of anxiety is its impact on decision making and flexible control of behavior. These cognitive constructs depend on proper functioning of the prefrontal cortex (PFC). Understanding how anxiety affects PFC encoding of cognitive events is of great clinical and evolutionary significance. Using a clinically valid experimental model, we find that, under anxiety, decision making may be skewed by salient and conflicting environmental stimuli at the expense of flexible top-down guided choices. We also find that anxiety suppresses spontaneous activity of PFC neurons, and weakens encoding of task rules by dorsomedial PFC neurons. These data provide a neuronal encoding scheme for how anxiety disengages PFC during decision making.

Impatience, aging, and leukocyte telomere length.

Yim et al. note in young college volunteers a correlation between a chemical marker of biological aging (leukocyte telomere length, abbr. LTL) and impatience (delay discounting). The wording of the abstract flirts with conflating correlations with causes, and directions of implied causes is not clear - does impatience causes cellular aging or does cellular aging cause impatience?  People with shorter telomeres might be more impatient because they are not going to be around as long?   (Or, do we have  a correlation as spurious as that noted between mortgage loan rates and sunspot frequency in the 1950's? Let the reader decide... ).

Significance

This paper makes a singular contribution to understanding the association between biological aging indexed by leukocyte telomeres length (LTL) and delay discounting measured in an incentivized behavioral economic task. In a large group of young, healthy undergraduates, steeper delay discounting is significantly associated with shorter LTL, while controlling for risk attitude and health-related behaviors. Notably, we found that delay discounting and risk attitude—two fundamental determinants of economic preferences—are independently associated with LTL. Moreover, for the first time to our knowledge, the effects of well-studied oxytocin and estrogen receptor polymorphisms are shown to specifically moderate the impact of impatience on LTL. Our work suggests a path to integrate behavioral economic methodology to supposed biological mechanisms associated with health outcomes. 

Abstract 

In a graying world, there is an increasing interest in correlates of aging, especially those found in early life. Leukocyte telomere length (LTL) is an emerging marker of aging at the cellular level, but little is known regarding its link with poor decision making that often entails being overly impatient. Here we investigate the relationship between LTL and the degree of impatience, which is measured in the laboratory using an incentivized delay discounting task. In a sample of 1,158 Han Chinese undergraduates, we observe that steeper delay discounting, indexing higher degree of impatience, is negatively associated with LTL. The relationship is robust after controlling for health-related variables, as well as risk attitude—another important determinant of decision making. LTL in females is more sensitive to impatience than in males. We then asked if genes possibly modulate the effect of impatient behavior on LTL. The oxytocin receptor gene (OXTR) polymorphism rs53576, which has figured prominently in investigations of social cognition and psychological resources, and the estrogen receptor β gene (ESR2) polymorphism rs2978381, one of two gonadal sex hormone genes, significantly mitigate the negative effect of impatience on cellular aging in females. The current results contribute to understanding the relationship between preferences in decision making, particularly impatience, and cellular aging, for the first time to our knowledge. Notably, oxytocin and estrogen receptor polymorphisms temper accelerated cellular aging in young females who tend to make impatient choices.

Political Substance Abuse: Donald Trump in Florida

I have to pass this on.

Seasonality in human cognitive brain responses

A brief review in PNAS points to an article by Meyer et.al.:

Mood changes have been linked to seasonality, but little is known about how other human brain functions may vary according to the seasons. Christelle Meyer et al. measured the cognitive brain function of 28 volunteers at different times of the year. For each testing period, each participant spent 5 days in the laboratory, devoid of seasonal cues, such as daylight, and without access to the external world. At the end of the 5-day period, the authors used functional MRI to assess sustained attention and higher executive function in two separate tasks. Performance on both tasks remained constant, but the brain resources used to complete each task changed with the seasons. Brain activity related to sustained attention peaked in June near the summer solstice and was lowest near the winter solstice. In contrast, working memory-related brain activity, a higher-order task, peaked in fall and was lower near the spring equinox. The authors report that these results did not correlate with endocrine measures, such as melatonin, or neurophysiological measures of alertness and sleep. According to the authors, in addition to daily circadian rhythms, certain brain functions may be more seasonal than previously appreciated and that seasonal rhythmicity may be specific to the cognitive process.

Seasonal variations in brain responses to two cognitive tasks, where the black lines represent the mean values.