Preverbal infants mentally represent social dominance.

Interesting observations from Thomsen et al:

Human infants face the formidable challenge of learning the structure of their social environment. Previous research indicates that infants have early-developing representations of intentional agents, and of cooperative social interactions, that help meet that challenge. Here we report five studies with 144 infant participants showing that 10- to 13-month-old, but not 8-month-old, infants recognize when two novel agents have conflicting goals, and that they use the agents’ relative size to predict the outcome of the very first dominance contests between them. These results suggest that preverbal infants mentally represent social dominance and use a cue that covaries with it phylogenetically, and marks it metaphorically across human cultures and languages, to predict which of two agents is likely to prevail in a conflict of goals.

Bias within - politics of the professoriat

In the Tuesday Science section of the NY Times, Tierny does a fascinating article on social psychologists, the folks who do research on racial prejudice, homophobia, sexism, stereotype threat and unconscious bias against minorities. He discusses a talk given by Jonathan Haidt at their national conference. Haight:

...polled his audience at the San Antonio Convention Center, starting by asking how many considered themselves politically liberal. A sea of hands appeared, and Dr. Haidt estimated that liberals made up 80 percent of the 1,000 psychologists in the ballroom. When he asked for centrists and libertarians, he spotted fewer than three dozen hands. And then, when he asked for conservatives, he counted a grand total of three.

“This is a statistically impossible lack of diversity,” Dr. Haidt concluded, noting polls showing that 40 percent of Americans are conservative and 20 percent are liberal. In his speech and in an interview, Dr. Haidt argued that social psychologists are a “tribal-moral community” united by “sacred values” that hinder research and damage their credibility — and blind them to the hostile climate they’ve created for non-liberals.

“Anywhere in the world that social psychologists see women or minorities underrepresented by a factor of two or three, our minds jump to discrimination as the explanation,” said Dr. Haidt, who called himself a longtime liberal turned centrist. “But when we find out that conservatives are underrepresented among us by a factor of more than 100, suddenly everyone finds it quite easy to generate alternate explanations.”

And one further clip from Tierney's article (which you should read).

Moynihan was shunned by many of his colleagues at Harvard as racist,” Dr. Haidt said. “Open-minded inquiry into the problems of the black family was shut down for decades, precisely the decades in which it was most urgently needed. Only in the last few years have liberal sociologists begun to acknowledge that Moynihan was right all along.”

Similarly, Larry Summers, then president of Harvard, was ostracized in 2005 for wondering publicly whether the preponderance of male professors in some top math and science departments might be due partly to the larger variance in I.Q. scores among men (meaning there are more men at the very high and very low ends). “This was not a permissible hypothesis,” Dr. Haidt said. “It blamed the victims rather than the powerful. The outrage ultimately led to his resignation. We psychologists should have been outraged by the outrage. We should have defended his right to think freely.”

Instead, the taboo against discussing sex differences was reinforced, so universities and the National Science Foundation went on spending tens of millions of dollars on research and programs based on the assumption that female scientists faced discrimination and various forms of unconscious bias. But that assumption has been repeatedly contradicted, most recently in a study published Monday in the Proceedings of the National Academy of Sciences by two Cornell psychologists, Stephen J. Ceci and Wendy M. Williams. After reviewing two decades of research, they report that a woman in academic science typically fares as well as, if not better than, a comparable man when it comes to being interviewed, hired, promoted, financed and published.

“Thus,” they conclude, “the ongoing focus on sex discrimination in reviewing, interviewing and hiring represents costly, misplaced effort. Society is engaged in the present in solving problems of the past.” Instead of presuming discrimination in science or expecting the sexes to show equal interest in every discipline, the Cornell researchers say, universities should make it easier for women in any field to combine scholarship with family responsibilities.

Walking improves your memory.

Erickson et al. show that exercise training increases the size of our hippocampus and improves memory. They divided 120 sedentary healthy adults in their mid-60s into two groups. From a summary:

One group walked around a track three times a week, building up to 40 minutes at a stretch; the other did a variety of less aerobic exercises, including yoga and resistance training with bands. After a year, brain scans showed that among the walkers, the hippocampus had increased in volume by about 2 percent on average; in the others, it had declined by about 1.4 percent. Such a decline is normal in older adults.

Here is the abstract:

The hippocampus shrinks in late adulthood, leading to impaired memory and increased risk for dementia. Hippocampal and medial temporal lobe volumes are larger in higher-fit adults, and physical activity training increases hippocampal perfusion, but the extent to which aerobic exercise training can modify hippocampal volume in late adulthood remains unknown. Here we show, in a randomized controlled trial with 120 older adults, that aerobic exercise training increases the size of the anterior hippocampus, leading to improvements in spatial memory. Exercise training increased hippocampal volume by 2%, effectively reversing age-related loss in volume by 1 to 2 y. We also demonstrate that increased hippocampal volume is associated with greater serum levels of BDNF, a mediator of neurogenesis in the dentate gyrus. Hippocampal volume declined in the control group, but higher preintervention fitness partially attenuated the decline, suggesting that fitness protects against volume loss. Caudate nucleus and thalamus volumes were unaffected by the intervention. These theoretically important findings indicate that aerobic exercise training is effective at reversing hippocampal volume loss in late adulthood, which is accompanied by improved memory function.

Did Frédéric Chopin have temporal lobe epilepsy?

I'm working up the incredible Chopin Fantasy in F minor for a spring concert, and am always eager to learn more about this remarkable composer (the technical requirements of his music conform to the natural musculature of the hands and arms in a way that no previous composer had...Bach and Beethoven sometimes make very unnatural and contortionistic demands.) Chopin was viewed as a tortured artist because at several performances he suddenly stopped in the middle of a piece and left the stage:

"I was about to play the [Funeral] March when, suddenly, I saw emerging from the half-open case of my piano those cursed creatures that had appeared to me on a lugubrious night at the Carthusian monastery. I had to leave for a while in order to recover myself, and after that I continued playing without saying a word."

An article by by Sara Reardon points to a paper by radiologist Manuel Vásquez Caruncho of Xeral-Calde Hospital in Lugo, Spain and neurologist Francisco Brañas Fernández that

...draws heavily from descriptions of Chopin's behavior by his friends and pupils and from his own writings. Their vivid recollections report finding the composer late at night, "pale in front of the piano, with wild eyes and his hair on end," unable to recognize them for short periods. He spoke often of a "cohort of phantoms" that haunted him, of seeing his friends as the walking dead, and feeling "like steam."
Only a handful of neurological disorders produce the phantasmagoria that tormented Chopin, who didn't abuse drugs or alcohol. The visions he described, such as demons crawling out of his piano, are now known as Lilliputian hallucinations: detailed visions of people or objects that are much smaller than they are in life. The authors rule out schizophrenia and other common psychoses because Chopin's hallucinations were visual, not auditory, and because he lacked other telltale symptoms such as eye problems or migraines. His short hallucinatory episodes are a hallmark of temporal lobe epilepsy,

Improving your cognitive toolkit - part II

This posts continues my abstracting of some of my favorite responses to the Edge.org annual question "What scientific concept would improve everybody's cognitive toolkit?"

Martin Seligman - PERMA

Is global well being possible?...The elements of well being must be exclusive, measurable independently of each other, and ideally, exhaustive. I believe there are five such elements and they have a handy acronym, PERMA, a shorthand abstraction for the enabling conditions of life:

P Positive Emotion
E Engagement
R Positive Relationships
M Meaning and Purpose
A Accomplishment

There has been forward movement in the measurement of these over the last decade. Taken together PERMA forms a more comprehensive index of well being than "life satisfaction" and it allows for the combining of objective and subjective indicators. PERMA can index the well being of individuals, of corporations, and of cities. The United Kingdom has now undertaken the measurement of well being for the nation and as one criterion — in addition to Gross Domestic Product — of the success of its public policy.

Steven Pinker - Positive-Sum Games

...when people become consciously aware of the game-theoretic structure of their interaction (that is, whether it is positive-, negative-, or zero-sum), they can make choices that bring them valuable outcomes — like safety, harmony, and prosperity — without their having to become more virtuous, noble, or pure...Some examples. Squabbling colleagues or relatives agree to swallow their pride, take their losses, or lump it to enjoy the resulting comity rather than absorbing the costs of continuous bickering in hopes of prevailing in a battle of wills. Two parties in a negotiation split the difference in their initial bargaining positions to "get to yes."

Has an increasing awareness of the zero- or nonzero-sumness of interactions in the decades since 1950 (whether referred to in those terms or not) actually led to increased peace and prosperity in the world? It's not implausible. International trade and membership in international organizations has soared in the decades that game-theoretic thinking has infiltrated popular discourse. And perhaps not coincidentally, the developed world has seen both spectacular economic growth and a historically unprecedented decline in several forms of institutionalized violence, such as war between great powers, war between wealthy states, genocides, and deadly ethnic riots. Since the 1990s these gifts have started to accrue to the developing world as well, in part because they have switched their foundational ideologies from ones that glorify zero-sum class and national struggle to ones that glorify positive-sum market cooperation. (All these claims can be documented from the literature in international studies.)

The enriching and pacifying effects of participation in positive-sum games long antedate the contemporary awareness of the concept. The biologists John Maynard Smith and Eörs Szathmáry have argued that an evolutionary dynamic which creates positive-sum games drove the major transitions in the history of life: the emergence of genes, chromosomes, bacteria, cells with nuclei, organisms, sexually reproducing organisms, and animal societies. In each transition, biological agents entered into larger wholes in which they specialized, exchanged benefits, and developed safeguards to prevent one from exploiting the rest to the detriment of the whole. The journalist Robert Wright sketched a similar arc in his book Nonzero and extended it to the deep history of human societies. An explicit recognition among literate people of the shorthand abstraction "positive-sum game" and its relatives may be extending a process in the world of human choices that has been operating in the natural world for billions of years.

Skilled object recognition uses both our left and right hemispheres

Bilalić et al. make the interesting observation that skilled chess players, while no faster or better than amateurs at geometric object recognition (which mainly engages left hemisphere), are more rapid than amateurs at identifying chess positions, while at the same time engaging additional areas of their right hemisphere. This expanded use of brain areas requires extensive training. (When the subjects were shown the chess diagrams, the novices looked directly at the pieces to recognize them, while the experts looked on the middle of the boards and took everything in with their peripheral vision.) (Wan et al. report a similar study in Japan examining experts in shogi, a game similar to chess. It highlights further brain areas involved in expertise.) Here is the Bilalić et al. abstract (dorsal means along the upper part of the brain, ventral is lower):

Our object recognition abilities, a direct product of our experience with objects, are fine-tuned to perfection. Left temporal and lateral areas along the dorsal, action related stream, as well as left infero-temporal areas along the ventral, object related stream are engaged in object recognition. Here we show that expertise modulates the activity of dorsal areas in the recognition of man-made objects with clearly specified functions. Expert chess players were faster than chess novices in identifying chess objects and their functional relations. Experts' advantage was domain-specific as there were no differences between groups in a control task featuring geometrical shapes. The pattern of eye movements supported the notion that experts' extensive knowledge about domain objects and their functions enabled superior recognition even when experts were not directly fixating the objects of interest. Functional magnetic resonance imaging (fMRI) related exclusively the areas along the dorsal stream to chess specific object recognition. Besides the commonly involved left temporal and parietal lateral brain areas, we found that only in experts homologous areas on the right hemisphere were also engaged in chess specific object recognition. Based on these results, we discuss whether skilled object recognition does not only involve a more efficient version of the processes found in non-skilled recognition, but also qualitatively different cognitive processes which engage additional brain areas.

The biology of morality

I have already pointed to a TED talk by Sam Harris, and thought I would pass on a few clips from a review of his related book, "The Moral Landscape - How Science Can Determine Human Values." On Harris:

...his dispensation is that “Faith, if it is ever right about anything, is right by accident.” In applying reason to questions of morality, Harris claims that we can define morality only as it relates to the well-being of conscious organisms and that such well-being is completely measurable using the methods of neurobiology. This suggests to him that any action can be clearly classified as moral (increasing well-being) or immoral (decreasing well-being) without ambiguity. However, it doesn't mean that there is only one answer to a question of morality. He contends that “the existence of multiple peaks on the moral landscape does not make them any less real or worthy of discovery. Nor would it make the difference between being on a peak and being stuck deep in a valley any less clear or consequential.” But Harris firmly disagrees with the moral relativist views that there is no clearly defined morality that cuts across different societies and that therefore all views of morality are equally meritorious. He writes, “Multiculturalism, moral relativism, political correctness, tolerance even of intolerance—these are the familiar consequences of separating facts and values on the left.” “My goal,” he states, “is to convince you that human knowledge and human values can no longer be kept apart.”

Harris isn't choosy when it comes to vilifying religions. He notes the willingness of many to ignore genocide or cases of sexual abuse within their churches while taking strong actions against individuals who perform abortions (or refuse to prohibit them). He also draws from history examples of undeniably immoral choices in the name of religion. Harris criticizes scientists for persisting in their faith and for failing to confront head-on a society that he thinks is mired in superstition.

Harris thinks too many scientists have compromised on principles. “Many of our secular critics worry that if we oblige people to choose between reason and faith, they will choose faith and cease to support scientific research.” Even the journal Nature upholds the idea of nonoverlapping magisteria of Gould. Harris complains, “It is one thing to be told that the pope is a peerless champion of reason and that his opposition to embryonic stem-cell research is both morally principled and completely uncontaminated by religious dogmatism; it is quite another to be told this by a Stanford physician who sits on the President's Council on Bioethics.”

One might conclude that although at one time the best way to define and enforce moral behavior was through revealed faith, as science and reason advance, we can chip away at the old edifice and build anew. Stories of a young-Earth creation now look rather untenable, but in the past they might have been the only way to instill awe and teach a new and meaningful moral code. Rather than nonoverlapping magisteria, the domains of science and religion are intermingling all the time. The Moral Landscape may represent a new beach-head in this quest.

Meanwhile...back in Wisconsin

As I sit at the keyboard in my Fort Lauderdale snowbird condo looking out the open patio door, gentle breeze, 72 degree Farenheit,

My younger partner, still in the working world, emails me an iPhone picture he just took of our rural snowbound Middleton, Wisconsin home.  The blizzard has shut down all commercial and educational facilities.

What would improve your cognitive toolkit?

My first MindBlog post in 2006 was a description of answers given to an annual question posed each year to prominent public intellectuals by Edge.org. The question for 2010 is "What scientific concept would improve everybody's cognitive toolkit?"

A "scientific concept" may come from philosophy, logic, economics, jurisprudence, or other analytic enterprises, as long as it is a rigorous conceptual tool that may be summed up succinctly (or "in a phrase") but has broad application to understanding the world...James Flynn has defined "shorthand abstractions" (or "SHA's") as concepts drawn from science that have become part of the language and make people smarter by providing widely applicable templates ("market", "placebo", "random sample," "naturalistic fallacy," are a few of his examples). His idea is that the abstraction is available as a single cognitive chunk which can be used as an element in thinking and debate.

I'm going to give brief sketches of a few responses that I found most interesting.   I try to edit  the author's point to a single declarative phrase, the 'single cognitive chunk'  requirement suggested above (I'm surprised that in most cases the authors didn't do this more effectively). I'll list a few in this post, and as I have time to continue reading through the 164 contributions, perhaps do some further posts...

Howard Gardner - Try to disprove your viewpoint.

"If American citizens, or, for that matter, citizens anywhere were motivated to decribe the conditions under which they would relinquish their beliefs, they would begin to think scientifically. And if they admitted that empirical evidence would not change their minds, then at least they'd have indicated that their views have a religious or an ideological, rather than a scientific basis.

Christian Keysers - Avoid the mirror fallacy

...our brain mirrors the states of the people we observe...When the person we see has the exact same body and brain as we do, mirroring would tell us what the other feels. Whenever the other person is different in some relevant way, however, mirroring will mislead us...The world is full of such fallacies: we feel dolphins are happy just because their face resembles ours while we smile or we attribute pain to robots in sci-fi movies.

George Lakoff - Be aware of the conceptual metaphors you are using.

All concepts are physical brain circuits deriving their meaning via neural cascades that terminate in linkage to the body. That is how embodied cognition arises...Primary metaphors are brain mappings linking disparate brain regions, each tied to the body in a different way. For example, More Is Up (as in "prices rose") links a region coordinating quantity to another coordinating verticality...Complex conceptual metaphors arise via neural bindings, both across metaphors and from a given metaphor to a conceptual frame circuit. Metaphorical reasoning arises when source domain inference structures are used for target domain reasoning via neural mappings... A central consequence is the huge range of concepts that use metaphor cannot be defined relative to the outside world, but are instead embodied via interactions of the body and brain with the world...Every time you think of paying moral debts, or getting bogged down on a project, or losing time, or being at a crossroads in a relationship, you are unconsciously activating a conceptual metaphor circuit in your brain, reasoning using it, and quite possibly making decisions and living your life on the basis of your metaphors. And that's just normal. There's no way around it!..But it can do harm if you are unaware of it.

Modern virtue - the religion of physical fittness

As I have morphed during my life from a devout teenage christian church organist into a crusty old materialistic atheist, I have found a new church in the cult of physical exercise and fitness. Virtue and badness can be simply measured by whether I have worked out today. Until I read this fascinating tribute to Jack LeLane, who recently died at the age of 96, I had not realized what a modern invention my church is, growing from the opening of his first gym in Oakland, CA. in 1936:

With “The Jack LaLanne Show,” he also had a hand in the spread — a contagion, really — of television programs exhorting viewers to rise up from their La-Z-Boys...An army of spandex missionaries was unleashed....What he left behind when he died last week...was not only a sweaty culture of relentless crunching and spinning but also the notion that fitness equals character, and that self-actualization begins with the self-discipline to get and stay in shape. In the post-LaLanne landscape, it’s not the eyes but the abdominals that are windows to the soul...A “new you” usually means a trimmer, tauter version, not someone who has learned to speak Mandarin or picked up woodworking skills...There’s a bullying strain to the modern fitness ethos, a blurred line between cheerleading and hectoring...When exercise comes wrapped in value judgments, does it wind up entangled in an anxiety that threatens the very resolve to get fit? As Mr. LaLanne was siring new methods for shaping up, he was fathering something else, too: a potent, and in some cases immobilizing, strain of contemporary guilt.

Modern conversation.

As relevant to this morning's previous post, I had to pass on today's Doonesbury cartoon, having noted during my kid's New Year's visit how our conversations transitioned seamlessly from periods of actual talking to tapping on our iPhones and back to talking again, no requirement that one excuse oneself from actual talk, the accepted procedure was just to suddenly divert attention and start tapping on the new prosthetic device. This clearly is how the world of 20- and 30-somethings now works.

Is our technology replacing our identity?

After publishing an optimistic book about the internet in 1995 ("Life on the Screen"), MIT social science professor Sherry Turkle has now written a darker tome, "Alone Together,"  worrying that we are moving more of our lives online and away from real physical human contacts. The first half of the book is about social robots. From Jonah Lehrer's review:

“Dependence on a robot presents itself as risk free,” Turkle writes. “But when one becomes accustomed to ‘companionship’ without demands, life with people may seem overwhelming.” A blind date can be a fraught proposition when there’s a robot at home that knows exactly what we need. And all she needs is a power outlet...The reason robots are such a slippery slope, according to Turkle, is that they take advantage of a deeply human instinct. When it comes to the perception of other minds, we are extremely gul­lible, bestowing agency on even the most inanimate of objects.

The second part of the book deals with Turkle's concern that the internet is becoming our way of being with other people, in a style that turns them into objects. (Why did I just text my friend instead of actually just calling and talking with him.)

...the online world is no longer a space of freedom and re­invention. Instead, we have been trapped by Facebook profiles and Google cache, in which verbs like “delete” and “erase” are mostly metaphorical...We aren’t “happy” anymore: we’re simply a semicolon followed by a parenthesis. Instead of talking on the phone, we send a text; instead of writing wistful letters, we edit our Tumblr blog...these obvious objections shouldn’t obscure the real mystery: If the Internet is such an alienating force, then why can’t we escape it? If Facebook is so insufferable, then why do hundreds of millions of people check their page every day?

My own experience is that my participation in social web sites has broadened my world of real world contacts and friends, as noted by Lehrer:

...despite our misgivings about the Internet, its effects on real-life relationships seem mostly positive, if minor. A 2007 study at Michigan State University involving 800 undergraduates, for instance, found that Facebook users had more social capital than abstainers, and that the site increased measures of “psychological well-being,” especially in those suffering from low self-esteem. Other studies have found that frequent blogging leads to increased levels of social support and integration and may serve as “the core of building intimate relationships.” One recurring theme to emerge from much of this research is that most people, at least so far, are primarily using the online world to enhance their offline relationships, not supplant them.

Our social brain - what are smiles for?

In this past Tuesday's NYTimes science section, Carl Zimmer offers a brief review of some of the many social functions served by our smiling at each other (signaling happiness, social bonding, embarrassment, dominance, etc.). He focuses on the work of Paula Niedenthal. I found this particular bit interesting:

In one study, she and her colleagues are testing the idea that mimicry lets people recognize authentic smiles. They showed pictures of smiling people to a group of students. Some of the smiles were genuine and others were fake. The students could readily tell the difference between them....Then Dr. Niedenthal and her colleagues asked the students to place a pencil between their lips. This simple action engaged muscles that could otherwise produce a smile. Unable to mimic the faces they saw, the students had a much harder time telling which smiles were real and which were fake.

The scientists then ran a variation on the experiment on another group of students. They showed the same faces to the second group, but had them imagine the smiling faces belonged to salesclerks in a shoe store. In some cases the salesclerks had just sold the students a pair of shoes — in which they might well have a genuine smile of satisfaction. In other trials, they imagined that the salesclerks were trying to sell them a pair of shoes — in which case they might be trying to woo the customer with a fake smile...In reality, the scientists use a combination of real and fake smiles for both groups of salesclerks. When the students were free to mimic the smiles, their judgments were not affected by what the salesclerk was doing...But if the students put a pencil in their mouth, they could no longer rely on their mimicry. Instead, they tended to believe that the salesclerks who were trying to sell them shoes were faking their smiles — even when their smiles were genuine. Likewise, they tended to say that the salesclerks who had finished the sale were smiling for real, even when they weren’t. In other words, they were forced to rely on the circumstances of the smile, rather than the smile itself.

Our Guts 'R Us

It dents my tidy self image just a bit when I read articles like this one from Atarashi et al. (summarized by Barnes and Powrie). A very indispensible part of my 'self' is an astounding 10¹⁴ bacteria that reside in the large intestine alone, alongside various viruses, fungi, protozoa, and parasites, all of which can affect chronic disease progression. Lee and Mazmanian point out that:

Although microbes have been classically viewed as pathogens, it is now well established that the majority of host-bacterial interactions are symbiotic. During development and into adulthood, gut bacteria shape the tissues, cells, and molecular profile of our gastrointestinal immune system. This partnership, forged over many millennia of coevolution, is based on a molecular exchange involving bacterial signals that are recognized by host receptors to mediate beneficial outcomes for both microbes and humans....specific aspects of the adaptive immune system are influenced by intestinal commensal bacteria. Understanding the molecular mechanisms that mediate symbiosis between commensal bacteria and humans may redefine how we view the evolution of adaptive immunity and consequently how we approach the treatment of numerous immunologic disorders.

The Lee and  Mazmanian review contains this striking graphic:

Legend: The microbiome of various anatomical locations of the human body. Numerous bacterial species colonize the mouth, upper airways, skin, vagina, and intestinal tract of humans. The phylogenetic trees show the speciation of bacterial clades from common ancestors at each anatomical site. Although the communities in different regions of the body share similarities, they each have a unique site-specific “fingerprint” made of many distinct microbes. Each site has a very high level of diversity, as shown by the individual lines on the dendrograms. Data are from the NIH-funded Human Microbiome Project; circles represent bacterial species whose sequences are known.

The  Atarashi et al. article demonstrates that

...indigenous species of Clostridium bacteria, a large component of our mammalian microbiota, promote anti-inflammatory immune responses by expanding and activating regulatory T cells...Oral inoculation of Clostridium during the early life of conventionally reared mice results in resistance to colitis and systemic immunoglobulin E responses in adult mice, suggesting a new therapeutic approach to autoimmunity and allergy.

These results are of some interest to us humans!

Some factoids on exercise and health.

I thought I would list out four interesting chunks from the Wellness Blog at the NY Times:

It's well know that exercise can be an antidote to depression. This is particularly relevant to people living in Northern regions with very short periods of daylight. How much exercise do you need to avoid feeling gloomy? Not much, it turns out. According to a study published in this month’s British Journal of Sports Medicine: a mere 20 minutes a week of any physical activity, whether sports, walking, gardening or even housecleaning, will do it... Exactly how much physical activity is required to obtain its health benefits? A review of dozens of studies on the health effects of exercise did:

ultimately reach some conclusions about how much — or, really, how little — exercise we each should be doing. That minimum amount of exercise required to see a significant lowering of your risk of dying prematurely was, they concluded, 500 MET minutes of exercise a week... A single MET, or Metabolic Equivalent of Task, is the amount of energy a person uses at rest. Two METs represent twice the energy burned at rest; four METs, four times the energy used at rest; and so on. Walking at three miles per hour is a 3.3-MET activity, while running at 6 miles an hour is a 10-MET activity. The committee concluded that a person needs to accumulate a weekly minimum of 500 MET minutes of exercise, which does not mean 500 minutes of exercise. Instead, 150 minutes a week (two and a half hours) of a moderate, three- to five-MET activity, such as walking, works out to be about 500 MET minutes. Half as much time (an hour and 15 minutes per week) spent on a 6-plus MET activity like easy jogging seems, according to the committee, to have similar health effects.

Interestingly, they did not find that exercise beyond a certain point conferred significant additional health benefits. Instead, the “dose response” for exercise, the committee found, is “curvilinear.” In other words, people who are the least active to start with get the most health benefit from starting to exercise. People who already are fit don’t necessarily get a big additional health benefit from adding more workout time to their regimens.

Of particular interest to a worrywart like myself who is extremely physically fit, but concerned about the normal loss of muscle mass that occurs in my age group (65-75) over the next ten years,  a recent study suggests that visiting the gym only once a week is sufficient to hold on to muscle mass and previous strength gains.

It has now been shown that weight resistance training, as well as aerobic exercise, boosts levels of the brain growth factor BNDF and cognitive enhancement (in rats, that is, and most likely us too.)

A further curious counterintuitive note:  Exercising increases the urge to drink alcohol,  and drinkers are more likely to exercise more.

Why loneliness is hazardous to your health

Greg Miller does an interesting review article in Science Magazine that describes numerous recent studies on the effect of loneliness on our physiology, health, and longevity. The article focuses on the work of John Cacioppo, a Univ. of Chicago psychologist who is credited with founding the field of social neuroscience. Here is the summary, followed by a few clips and rephrasings from the article:

In a steady stream of recent papers, social psychologists have identified several potentially unhealthy changes in the cardiovascular, immune, and nervous systems of chronically lonely people. The findings could help explain why epidemiological studies have often found that socially isolated people have shorter life spans and increased risk of a host of health problems, including infections, heart disease, and depression. The work also adds a new wrinkle, suggesting that it's the subjective experience of loneliness that's harmful, not the actual number of social contacts a person has. An impressive network of collaborations with researchers in other disciplines is now pioneering a new science of loneliness.

...scores of studies have found that people who lack social support are more prone to a variety of ailments. An analysis of 148 of these studies, published in the July 2010 issue of PLoS Medicine, suggests that social isolation increases the risk of death about as much as smoking cigarettes and more than either physical inactivity or obesity...loneliness is a health risk on its own, apart from conditions such as depression or stress that are common fellow travelers. More specifically, it seems to be the subjective experience of loneliness that's important for people's well-being rather than any objective measure of social connectivity (the number of close contacts someone has, for example).

The UCLA Loneliness Scale is based on a questionnaire that tries to size up how people perceive their social situation, with questions about how often they feel a lack of companionship, feel they have no one to talk to, or feel out of tune with those around them....When people score high on this scale, they also tend to exhibit several physiological changes that effectively put the body in a state of alert... people exhibit higher vascular resistance, a tightening of the arteries that raises blood pressure, forces the heart to work harder, and contributes to wear and tear on vessels...They have elevated molecular markers of stress - cortisol and epinephrine are elevated in saliva and urine, respectively.

Lonely people exhibit increased activity for several genes encoding signaling molecules that promote inflammation and decreased activity for genes that normally put the brakes on inflammation. They also show diminished activity in genes that help mount a defense against viral invaders....This..jibes with epidemiologic findings that socially isolated people are more susceptible to viruses, from the common cold to HIV, and to cardiovascular disease, which has been linked to excess inflammation.

Those who are lonelier, as rated by the UCLA Loneliness Scale, exhibit less activation in the ventral striatum, a component of the brain's reward circuitry, when they view pictures of smiling faces. They also show increased reactivity in the threat-detecting amygdala to pictures of angry or fearful faces.

...loneliness is partly heritable..a recent study, published in the July 2010 issue of Behavioral Genetics, used an abbreviated version of the UCLA Loneliness Scale in a survey sent to 8683 twins and family members. In this group, genetics accounted for 37% of the variability in loneliness, somewhat lower than in some previous studies. Overall, the heritability of loneliness is comparable to that of depression, but less than that of traits such as high blood pressure and cholesterol levels.

The news isn't all bad...Even for hard cases, Cacioppo believes loneliness can be overcome. He and colleagues recently conducted a meta-analysis of 20 studies on interventions for loneliness. Simply providing social support doesn't seem to work, especially if people know they're being looked after...The most effective interventions were those that borrowed methods from cognitive behavioral therapy to shift people's attention and interpretation of social situations in a more positive direction.

The chemistry of enjoying music

Robert Zatorre is an imaginative and productive musician/scientist. His website offers a cornucopia of information on the brain and music. A recent study from his group published in Nature Neuroscience observes how the 'pleasure molecule' dopamine and different brain regions change activity during the anticipation of, and emotional response to, music (many other physiological variables are also measured). His website lets you listen to the musical stimuli used in the studies, some of the most emotional chunks of music ever written. Just listening to a few of them reduced me to a puddle. (Now I know where to go for a quick emotional pleasure boost!). Jonah Lehrer's review of this work is excellent, a much better summary than I would do.  Here is Zatorre's abstract:

Music, an abstract stimulus, can arouse feelings of euphoria and craving, similar to tangible rewards that involve the striatal dopaminergic system. Using the neurochemical specificity of [11C]raclopride positron emission tomography scanning, combined with psychophysiological measures of autonomic nervous system activity, we found endogenous dopamine release in the striatum at peak emotional arousal during music listening. To examine the time course of dopamine release, we used functional magnetic resonance imaging with the same stimuli and listeners, and found a functional dissociation: the caudate was more involved during the anticipation and the nucleus accumbens was more involved during the experience of peak emotional responses to music. These results indicate that intense pleasure in response to music can lead to dopamine release in the striatal system. Notably, the anticipation of an abstract reward can result in dopamine release in an anatomical pathway distinct from that associated with the peak pleasure itself. Our results help to explain why music is of such high value across all human societies.

Age defying or denying? Real life among the old old.

Studies or ideas about human aging are frequently the subjects of posts in this blog (given that I have a vested interest in the aging of yours truly...), and I thought this perspective offered by Susan Jacoby, author of the forthcoming “Never Say Die: The Myth and Marketing of the New Old Age,” as she turns 65, was a very sane one:

..people my age and younger still pretend that old age will yield to what has long been our generational credo — that we can transform ourselves endlessly, even undo reality, if only we live right. “Age-defying” is a modifier that figures prominently in advertisements for everything from vitamins and beauty products to services for the most frail among the “old old,” as demographers classify those over 85. You haven’t experienced cognitive dissonance until you receive a brochure encouraging you to spend thousands of dollars a year for long-term care insurance as you prepare to “defy” old age....“Deny” is the word the hucksters of longevity should be using. Nearly half of the old old — the fastest-growing segment of the over-65 population — will spend some time in a nursing home before they die, as a result of mental or physical disability.

Researchers who were part of a panel discussion titled “90 Is the New 50,” presented at the World Science Festival in 2008, spoke to a middle-aged, standing-room-only audience about imminent medical miracles...The trouble with expecting 90 to become the new 50 is it can stop rational discussion — on a societal as well as individual level — about how to make 90 a better 90. This fantasy is a lot like waiting for Prince Charming, in that it doesn’t distinguish between hope and reasonable expectation.

The risk of dementia, of which Alzheimer’s is the leading cause, doubles every five years after 65...Contrary to what the baby boom generation prefers to believe, there is almost no scientifically reliable evidence that “living right” — whether that means exercising, eating a nutritious diet or continuing to work hard — significantly delays or prevents Alzheimer’s. This was the undeniable and undefiable conclusion in April of a major scientific review sponsored by the National Institutes of Health...Good health habits and strenuous intellectual effort are beneficial in themselves, but they will not protect us from a silent, genetically influenced disaster that might already be unfolding in our brains. I do not have the slightest interest in those new brain scans or spinal fluid tests that can identify early-stage Alzheimer’s. What is the point of knowing that you’re doomed if there is no effective treatment or cure? As for imminent medical miracles, the most realistic hope is that any breakthrough will benefit the children or grandchildren of my generation, not me.

Jacoby on her own situation:

I would rather share the fate of my maternal forebears — old old age with an intact mind in a ravaged body — than the fate of my other grandmother. But the cosmos is indifferent to my preferences, and it is chilling to think about becoming helpless in a society that affords only the most minimal support for those who can no longer care for themselves. So I must plan, as best I can, for the unthinkable.

..I must find someone I trust to make medical decisions for me if I cannot make them myself. This is a difficult emotional task, and it does not surprise me, for all of the public debate about end-of-life care in recent years, that only 30 percent of Americans have living wills. Even fewer have actually appointed a legal representative, known as a health care proxy, to make life-and-death decisions...I can see that the “90 is the new 50” crowd might object to my thinking more about worst-case scenarios than best-case ones. But if the best-case scenario emerges and I become one of those exceptional “ageless” old people so lauded by the media, I won’t have a problem. I can also take it if fate hands me a passionate late-in-life love affair, a financial bonanza or the energy to write more books in the next 25 years than I have in the past 25.

Distortions of mind perception in psychopathology

A really interesting perspective comes from Daniel Wegner and co-workers in the Psychology Dept. at Harvard. (Wegner's book, "The Illusion of Conscious Will" is in my cannon of must-read books on self and consciousness). From their introduction:

Originally thought to proceed along a single dimension, mind perception has been revealed in a factor-analytic study to occur along independent dimensions of experience (e.g., the capacity for pleasure, fear, hunger) and agency (e.g., the capacity for self-control, planning, memory. Adult humans are typically seen as capable of both experience and agency, whereas children and animals are seen as capable of mainly experience. Gods and robots are seen as capable of mainly agency, and the dead are seen as capable of neither.

We suggest that a number of disorders may be characterized as specific distortions of mind perception, atypical ascriptions of mental capacities to other entities....Successful interaction with the world requires knowing which entities have minds and which do not. Mind perception can therefore be distorted by overperception (perceiving a nonexistent mind) and underperception (failing to perceive an existent mind). Research suggests that both can be associated with adverse consequences for perceivers and targets, consequences that range from social faux pas to violence and death. For example, the overperception of mind in infants can lead to child abuse, but the underperception of mind in adults can lead to the denial of moral rights.

Their abstract:

It has long been known that psychopathology can influence social perception, but a 2D framework of mind perception provides the opportunity for an integrative understanding of some disorders. We examined the covariation of mind perception with three subclinical syndromes—autism-spectrum disorder, schizotypy, and psychopathy—and found that each presents a unique mind-perception profile. Autism-spectrum disorder involves reduced perception of agency in adult humans. Schizotypy involves increased perception of both agency and experience in entities generally thought to lack minds. Psychopathy involves reduced perception of experience in adult humans, children, and animals. Disorders are differentially linked with the over- or underperception of agency and experience in a way that helps explain their real-world consequences.

Smart Phone people...

A bit of humour from the TalkAndroid website (click on image to enlarge and read the captions):