The neuroscience of love

Larry Young offers this latest installment in Nature's "Being Human" series on a topic I have mentioned in a number of previous posts. He notes that animal studies that demystified emotions such as fear and anxiety are beginning to illuminate the mental states associated with love. This has implications for the nature of human sexuality — and could even lead to drugs to enhance or diminish our love for another. Tierney comments (the graphic is from his article) on Young's essay , suggesting that

...the really good news, as I see it, is that we might reverse-engineer an anti-love potion, a vaccine preventing you from making an infatuated ass of yourself.

Here are some clips from Young:

We are not alone in being able to form intense and enduring social ties. Take the mother–infant bond. Whether or not the emotional connection between a ewe and her lamb, or a female macaque and her offspring, is qualitatively similar to human motherly love, it is highly likely that these relationships share evolutionarily conserved brain mechanisms. In humans, rats and sheep, the hormone oxytocin is released during labour, delivery and nursing. In ewes, an infusion of oxytocin into the brain results in rapid bonding with a foreign lamb...There is intriguing overlap between the brain areas involved in vole pair bonding and those associated with human love. Dopamine-related reward regions of the human brain are active in mothers viewing images of their child. Similar activation patterns are seen in people looking at photographs of their lovers.

Pair bonding in males involves similar brain circuitry to that in females, but different neurochemical pathways. In male prairie voles, for example, vasopressin — a hormone related to oxytocin — stimulates pair bonding, aggression towards potential rivals, and paternal instincts, such as grooming offspring in the nest. Variation in a regulatory region of the vasopressin receptor gene, avpr1a, predicts the likelihood that a male vole will bond with a female.

Similarly, in humans, different forms of the AVPR1A gene are associated with variation in pair bonding and relationship quality. A recent study shows that men with a particular AVPR1A variant are twice as likely as men without it to remain unmarried, or when married, twice as likely to report a recent crisis in their marriage. Spouses of men with the variant also express more dissatisfaction in their relationships than do those of men lacking it. For both voles and humans, AVPR1A genetic polymorphisms predict how much vasopressin receptor is expressed in the brain.

The view of love as an emergent property of a cocktail of ancient neuropeptides and neurotransmitters raises important issues for society. For one thing, drugs that manipulate brain systems at whim to enhance or diminish our love for another may not be far away. Experiments have shown that a nasal squirt of oxytocin enhances trust and tunes people into others' emotions. Internet entrepreneurs are already marketing products such as Enhanced Liquid Trust, a cologne-like mixture of oxytocin and pheromones "designed to boost the dating and relationship area of your life". Although such products are unlikely to do anything other than boost users' confidence, studies are under way in Australia to determine whether an oxytocin spray might aid traditional marital therapy.

We don't yet know whether the drugs commonly used to treat disorders from depression to sexual dysfunction affect people's relationships by altering neurochemistry. But both Prozac and Viagra influence the oxytocin system. The quality of patients' relationships should be included in the list of variables assessed in controlled psychiatric drug studies.

Followup on 'Reinventing the sacred'....

I relay here (with permission) an email comment on the 'Reinventing the Sacred' post and suggest that you look at several other thoughtful comments at the end of that post.

Perhaps philosophy has something to offer the 'hard core materialist'. I recently read "Illness" by Havi Carel which I must say was a truly moving experience. Meditations on death and meaning using the authors knowledge of Greek Philosophy and Phenomenology enabled her to 'live well' with illness. This is something that a naturalistic bioscience approach would have trouble with?

You might like the thoughts of the former Bishop of Edinburgh Richard Holloway "Looking in the distance -the human search for meaning" is one of his excellent books. Holloway, who is now in charge of the Arts Council,sees religion as poetry and metaphor rather than a competition with science which seeks to search for 'material' truth.....Most people appear to need a bit of both and there does seem a universal need for spirituality and engagement-which does not have to be gained by participation in organized religion. Some of the offshoots of immersion in religious practices and spiritual disciplines do appear to have material benefit too (in terms of health and cohesion of community) but this is another discussion perhaps.

Bees on cocaine...

Here is an item that falls into the 'random curious stuff' category of this blog's subheading:

A common speculation is that the cocaine that triggers reward pathways in our brains evolved as an insecticide that protects the coca plant. Barron et al. have now found a reward effect in bees. By examining the honey bee dance--the means by which bees signal the availability of resources to their hive-mates--they found that dosing the bees with cocaine increased both the likelihood and rate of dance after foraging; furthermore, the bees exhibited behavior consistent with a withdrawal effect when the drug was withheld after chronic treatment. They suggest that the response to the drug may be similar in humans and bees. Here is their abstract:

The role of cocaine as an addictive drug of abuse in human society is hard to reconcile with its ecological role as a natural insecticide and plant-protective compound, preventing herbivory of coca plants (Erythroxylum spp.). This paradox is often explained by proposing a fundamental difference in mammalian and invertebrate responses to cocaine, but here we show effects of cocaine on honey bees (Apis mellifera L.) that parallel human responses. Forager honey bees perform symbolic dances to advertise the location and value of floral resources to their nest mates. Treatment with a low dose of cocaine increased the likelihood and rate of bees dancing after foraging but did not otherwise increase locomotor activity. This is consistent with cocaine causing forager bees to overestimate the value of the floral resources they collected. Further, cessation of chronic cocaine treatment caused a withdrawal-like response. These similarities likely occur because in both insects and mammals the biogenic amine neuromodulator systems disrupted by cocaine perform similar roles as modulators of reward and motor systems. Given these analogous responses to cocaine in insects and mammals, we propose an alternative solution to the paradox of cocaine reinforcement. Ecologically, cocaine is an effective plant defence compound via disruption of herbivore motor control but, because the neurochemical systems targeted by cocaine also modulate reward processing, the reinforcing properties of cocaine occur as a `side effect'.

MRI in the courtroom as witness on pain?

Greg Miller notes, in his report on a Stanford Law School Event, that because pain pathways in the brain are better understood than those underlying lying, pain detection is more likely to be the first fMRI application to find widespread use in the courtroom.

...pain is an issue in about half of all tort cases, which include personal injury cases. Billions of dollars are at stake. Yet people with real pain are sometimes unable to prove it, and malingerers sometimes win cases by faking it...However, using fMRI as a painometer isn't straightforward. For starters, said Katja Wiech, a cognitive neuroscientist at University College London, pain sensitivity varies considerably from one person to the next. It's also influenced by psychological factors such as anxiety (which tends to make pain worse) and attention (focusing on pain makes it worse; distractions take the edge off). Such influences also show up in fMRI scans, Wiech said. Moreover, she and others noted that several studies have found broad overlap in the brain regions activated by real and imagined pain--something that could be exploited by plaintiffs with bogus claims.

A. Vania Apkarian, a neuroscientist at Northwestern University in Evanston, Illinois, was more optimistic. His group has found that activity in the medial prefrontal cortex and the right insula correlates well with pain intensity and the duration of chronic pain, respectively, in people with chronic back pain. "This is an objective measure of pain in these patients," Apkarian said. Based on these and other findings, he predicted that fMRI will be courtroom-ready sooner than others had suggested. "Maybe not in 2008, maybe in 2012," he said. "It's inevitable."

Apkarian's data looked promising to several legal experts in attendance. "You scientists care more about causation than we do in the law," said Stanford law professor Henry "Hank" Greely. "If the correlation is high enough, … we would see that as a useful tool." Indeed, Greely and others noted, even if fMRI can't provide a perfectly objective measure of pain, it may still be better than the alternatives. "We let people get on the stand … and say all kinds of things that may or may not be true," said William Fletcher, a judge on the U.S. Court of Appeals for the Ninth Circuit.

Sneakiness and brain size

I have a huge backlog of potential mindblog posts which haven't yet made it into the two posts per day routine I have set up. They are interesting, but keep getting pushed back in the queue by newer material that is appearing. Here is an engaging piece from Natalie Angier, motivated perhaps by the Madoff scandal, on deception in humans and other animals - the 'lying in everyday life' that lubricates human and animal social interactions.

...[there is] a direct relationship between sneakiness and brain size. The larger the average volume of a primate species’ neocortex — the newest, “highest” region of the brain — the greater the chance that the monkey or ape would pull a stunt like this one described in The New Scientist: a young baboon being chased by an enraged mother intent on punishment suddenly stopped in midpursuit, stood up and began scanning the horizon intently, an act that conveniently distracted the entire baboon troop into preparing for nonexistent intruders.

...researchers found that the college students told an average of two lies a day, community members one a day, and that most of the lies fell into the minor fib category...There is a counterintuitive motivation not to detect lies, or we would have become much better at it...you may not really want to know that the dinner you just cooked stinks, or even that your spouse is cheating on you.

The article notes a further number of interesting deceptive behaviors in humans and other animals.

We infer rather than perceive the moment we decided to act.

Banks and Isham do a further followup (see this post for a previous followup) on the famous Libet experiment that showed that the reported time of a decision to perform a simple action is at least 300 ms after the onset of brain activity that normally precedes the action. They propose that the reported time is not uniquely determined by any generator of the readiness potential (the commonly head view), but rather is the time participants select on the basis of available cues, chief among them being the apparent time of response. From their abstract:

In Experiment 1, we presented deceptive feedback (an auditory beep) 5 to 60 ms after the action to signify a movement time later than the actual movement. The reported time of decision moved forward in time linearly with the delay in feedback, and came after the muscular initiation of the response at all but the 5-ms delay. In Experiment 2, participants viewed their hand with and without a 120-ms video delay, and gave a time of decision 44 ms later with than without the delay. We conclude that participants' report of their decision time is largely inferred from the apparent time of response. The perception of a hypothetical brain event prior to the response could have, at most, a small influence.

Anxiety correlates with diminished prefrontal control of attention.

Sonia J Bishop, in an article in Nature Neuroscience, makes the case that trait anxiety (i.e. stable ongoing anxiety tendencies not related to a specific sudden threat) may be characterized by impaired recruitment of prefrontal mechanisms that are critical to the active control of attention when the task at hand does not fully govern the allocation of attention. She proposes that this deficit does not arise as a result of current or state levels of anxiety, but instead reflects an underlying trait characteristic that influences attentional processing regardless of the presence or absence of threat-related stimuli. This may interact with state anxiety influences on subcortical threat detection mechanisms to account for the threat-related attentional biases associated with clinical anxiety. It may also account for observations that anxious individuals show deficits across a range of non-affective tasks that place demands on attentional or cognitive control. Here is her abstract:

Many neurocognitive models of anxiety emphasize the importance of a hyper-responsive threat-detection system centered on the amygdala, with recent accounts incorporating a role for prefrontal mechanisms in regulating attention to threat. Here we investigated whether trait anxiety is associated with a much broader dysregulation of attentional control. Volunteers performed a response-conflict task under conditions that posed high or low demands on attention. High trait-anxious individuals showed reduced prefrontal activity and slower target identification in response to processing competition when the task did not fully occupy attentional resources. The relationship between trait anxiety and prefrontal recruitment remained after controlling for state anxiety. These findings indicate that trait anxiety is linked to impoverished recruitment of prefrontal attentional control mechanisms to inhibit distractor processing even when threat-related stimuli are absent. Notably, this deficit was observed when ongoing task-related demands on attention were low, potentially explaining the day-to-day difficulties in concentration that are associated with clinical anxiety.

How do you feel — now? The anterior insula and human awareness

In a perspectives article in Nature Neuroscience Bud Craig proposes that the anterior insula plays a fundamental role in human awareness (if you simply enter 'anterior insula' in google images you can see depictions of the structures for yourself, or see the figure below). Here is his abstract, followed by a description of the structure and then his model for the involvement of the insula in awareness:

The anterior insular cortex (AIC) is implicated in a wide range of conditions and behaviours, from bowel distension and orgasm, to cigarette craving and maternal love, to decision making and sudden insight. Its function in the re-representation of interoception offers one possible basis for its involvement in all subjective feelings. New findings suggest a fundamental role for the AIC (and the von Economo neurons it contains) in awareness, and thus it needs to be considered as a potential neural correlate of consciousness.

A photograph of the left insular cortex of a human patient. The human insular cortex is a distinct but hidden lobe of the brain. It is disproportionately (approx30%) enlarged in the human relative to the macaque monkey. It has 5–7 oblique gyri, but its morphology is quite variable, even between the two sides. Primary interoceptive representations are located in the dorsal posterior insula and re-represented in a polymodal integrative zone in the mid-insula and again in the anterior insular cortex (AIC). The primary interoceptive, gustatory and vagal representations extend to the anterior limit of the insula in macaques but only to the middle of the insula in humans, which suggests that the AIC of humans has no equivalent in the monkey. The most anterior and ventral (inferior) portion of the human insula that adjoins the frontal operculum is probably the most recently evolved, because this part (as well as the anterior cingulate cortex) contains von Economo neurons. as, anterior short insular gyrus; al, anterior long insular gyrus; ac, accessory gyrus; APS, anterior peri-insular sulcus; H, Heschl's gyrus; IPS, inferior peri-insular sulcus; ms, middle short insular gyrus; ps, posterior short insular gyrus; pl, posterior long insular gyrus; SPS, superior peri-insular sulcus. Photograph is courtesy of Professor Thomas P. Naidich, Mount Sinai Medical Center, New York.

Cartoons illustrating features of the proposed structural model of awareness. a | The posited integration of salient activity, progressing from the posterior insula (left) to the anterior insula (right). The primary interoceptive representations of feelings from the body provide a somatotopic foundation that is anchored by the associated homeostatic effects on cardiorespiratory function, as indicated by the focus of the colours in the chest. The integration successively includes homeostatic, environmental, hedonic, motivational, social and cognitive activity to produce a 'global emotional moment', which represents the sentient self at one moment of time. b | The top cartoon shows how a series of global emotional moments can produce a cinemascopic 'image' of the sentient self across time. The lower cartoon shows how the proposed model can produce a subjective dilation of time during a period of high emotional salience, when global emotional moments are rapidly 'filled up'. ACC, anterior cingulate cortex; DLPFC, dorsolateral prefrontal cortex; VMPFC, ventromedial prefrontal cortex.

A trick for appreciating the present moment

How natural or easy is it to relish our daily life experiences? Every self-help book you pick up says we should "stop and smell the roses." Kurtz looks at temporal scarcity as a motivator. His abstract:

Both psychological research and conventional wisdom suggest that it can be difficult to attend to and derive enjoyment from the pleasant things in life. The present study examined whether focusing on the imminent ending of a positive life experience can lead to increased enjoyment. A temporal distance manipulation was used to make college graduation seem more or less close at hand. Twice a week over the course of 2 weeks, college students were told to write about their college life, with graduation being framed as either very close or very far off. As predicted, thinking about graduation as being close led to a significant increase in college-related behaviors and subjective well-being over the course of the study. The present research provides support for the counterintuitive hypothesis that thinking about an experience's ending can enhance one's present enjoyment of it.

Unconscious threats increase moral affirmations

Proulx and Heine probe the "meaning-maintenance model," that proposes that whenever an individual's mental representations of expected associations (e.g., scripts, schemas, paradigms) are violated by unexpected experiences, this provokes an effort to regain a sense of meaning. The abstract, followed by a bit of explanation:

The meaning-maintenance model posits that threats to schemas lead people to affirm unrelated schemas. In two studies testing this hypothesis, participants who were presented with a perceptual anomaly (viz., the experimenter was switched without participants consciously noticing) demonstrated greater affirmation of moral beliefs compared with participants in a control condition. Another study investigated whether the schema affirmation was prompted by unconscious arousal. Participants witnessed the changing experimenter and then consumed a placebo. Those who were informed that the placebo caused side effects of arousal did not show the moral-belief affirmation observed in the previous studies, as they misattributed their arousal to the placebo. In contrast, those who were not informed of such side effects demonstrated moral-belief affirmation. The results demonstrate the functional interchangeability of different meaning frameworks, and highlight the role of unconscious arousal in prompting people to seek alternative schemas in the face of a meaning threat.

A bit more explanation:

In the changing-experimenter condition, while participants answered questions about entertainment, the female research assistant conducting the experiment was surreptitiously switched with another, identically dressed female experimenter. The first experimenter went to a filing cabinet to retrieve the next questionnaire, and after opening the filing cabinet, she stepped back and was replaced by the second experimenter, who shut the cabinet and continued the experiment (a video of the change can be viewed on the Web at http://www.psych.ubc.ca/~heine/MMMSwitch.wmv). In the mortality-salience condition, participants completed a standard mortality-salience manipulation by answering two questions about their own death. Previous studies have demonstrated that reminding participants of their eventual death provokes compensatory affirmation of alternative meaning frameworks. The mortality-salience condition was included to compare its results with those of our changing-experimenter condition.

To test affirmation of moral beliefs, subjects read a hypothetical report about the arrest of a prostitute and were asked to set a bond for the prostitute as if they were a judge reviewing the case. The rationale for this latter measure is that people are motivated to maintain their cultural worldview and will seek to punish individuals who act in ways that are inconsistent with that worldview. Participants in the changing-experimenter and mortality-salience conditions set a higher bond than did participants in the control condition

Reinventing the sacred

Those of us who are hard core materialists and have no use for explanations of the natural order provided by any of the main religions do have the problem of aridity. Being an atheistic secularist is not as warm and cuddly as the warm blanket of religious certainty and the social support provided by some religious settings. Even though I agree with sentiments in such recent books as "The God Delusion", "The end of Faith" and "God is not Great" I wish they could come forward with more compelling alternatives for maintaining the robustness of our evolved psychology.

Stuart Kauffman, the guy who has done a number of books on chaos, self organization, and emergence theory, has stepped forward to offer a new book, "Reinventing the Sacred," in which he suggests that we turn our reverence towards a "natural God" seen not as a supernatural Creator but as the natural creativity in the universe - a universe in which the unpredictable emergence of novelty is a daily occurrence.

"If we reinvent the sacred to mean the wonder of the creativity in the universe, biosphere, human history, and culture, are we not inevitably invited to honor all of life and the planet that sustains it?"

Noble sentiments, indeed, but still not developed into a form accessible or useful to the vast majority of humans who crave certainly and structure in their lives. "Unpredictable emergence of novelty" is not exactly a warm blanket. I wish I had any better ideas.....

Excuses: both ego defense and self sabotage

Benedict Cary has a nice piece in the Tuesday Science NYTimes section

...genuine excuse artisans — and there are millions of them — don’t wait until after choking to practice their craft. They hobble themselves, in earnest, before pursuing a goal or delivering a performance. Their excuses come preattached: I never went to class. I was hung over at the interview. I had no idea what the college application required...The urge goes well beyond a mere lowering of expectations, and it has more to do with protecting self-image than with psychological conflicts rooted in early development, in the Freudian sense...As a short-term strategy, self-handicapping is often no more than an exercise in self-delusion. Studies of college students have found that habitual handicappers — who skip a lot of classes; who miss deadlines; who don’t buy the textbook — tend to rate themselves in the top 10 percent of the class, though their grades slouch between C and D...The important thing for some is, no matter the method, to avoid considering the alternative explanation...as in the Marlon Brando line from "On the Waterfront": "I coulda been a contender."

Ramachandran on qualia and the self.

His bottom line, in an essay in Edge, is that the Qualia problem (how can a martian that knows every physical wiring detail of my seeing red actually have my experience of red) is a pseudo-problem, like two sides of a Moebius strip that look utterly different from our ant-like perspective but are in reality a single surface. From his essay:

The problem of self, on the other hand, is an empirical one that can be solved—or at least explored to its very limit—by science. If and when we do it will be a turning point in the history of science. Neurological conditions have shown that the self is not the monolithic entity it believes itself to be. It seems to consist of many components each of which can be studied individually, and the notion of one unitary self may well be an illusion. (But if so we need to ask how the illusion arises; was it an adaptation acquired through natural selection?)

Ramachandran then goes on to describe the fascinating variations in our sense of self that can be correlated with brain changes. In a previous essay on mirror neurons he

...speculated that these neurons can not only help simulate other people's behavior but can be turned "inward"—as it were—to create second-order representations or metarepresentations of your own earlier brain processes. This could be the neural basis of introspection, and of the reciprocity of self awareness and other awareness. There is obviously a chicken-or-egg question here as to which evolved first, but that is tangential to my main argument.... The main point is that the two co-evolved, mutually enriching each other to create the mature representation of self that characterizes modern humans. Our ordinary language illustrates this, as when we say "I feel a bit self conscious", when I really mean that I am conscious of others being conscious of me. Or when I speak of being self critical or experiencing "self-pity". (A chimp could—arguably—feel pity for a begging chimp, but I doubt whether it would ever experience self-pity.)

I also suggest that although these neurons initially emerged in our ancestors to adopt another's allocentric visual point of view, they evolved further in humans to enable the adoption of another's metaphorical point of view. ("I see it from his point of view" etc.) This, too, might have been a turning point in evolution although how it might have occurred is deeply puzzling.

Aging - Memory decline, sugar control, and emotional memories

Great.....now I learn another way in which my aging brain can fail to remember - the worsening of glucose regulation with aging permits more glucose spikes which reduce blood flow to the dentate gyrus in our hippocampus (required for new memory formation). Perhaps on the more positive side, memories carry less emotion in older people, apparently because their processing moves towards frontal and away from limbic areas.

Get religious to improve self control?

Here is a curious piece by John Tierney noting the work of Michael McCullouch, who provides evidence that religiosity correlates with higher self-control among adults.

“Brain-scan studies have shown that when people pray or meditate, there’s a lot of activity in two parts of brain that are important for self-regulation and control of attention and emotion,” he said. “The rituals that religions have been encouraging for thousands of years seem to be a kind of anaerobic workout for self-control.”

In a study published by the University of Maryland in 2003, students who were subliminally exposed to religious words (like God, prayer or bible) were slower to recognize words associated with temptations (like drugs or premarital sex). Conversely, when they were primed with the temptation words, they were quicker to recognize the religious words.

What should a heathen like myself do?

Dr. McCullough’s advice is to try replicating some of the religious mechanisms that seem to improve self-control, like private meditation or public involvement with an organization that has strong ideals.

Cleanliness reduces the severity of moral judgements.

From Schnall et al. at the Univ. of Plymouth. Here is their abstract, followed by a bit of explanation:

Theories of moral judgment have long emphasized reasoning and conscious thought while downplaying the role of intuitive and contextual influences. However, recent research has demonstrated that incidental feelings of disgust can influence moral judgments and make them more severe. This study involved two experiments demonstrating that the reverse effect can occur when the notion of physical purity is made salient, thus making moral judgments less severe. After having the cognitive concept of cleanliness activated (Experiment 1) or after physically cleansing themselves after experiencing disgust (Experiment 2), participants found certain moral actions to be less wrong than did participants who had not been exposed to a cleanliness manipulation. The findings support the idea that moral judgment can be driven by intuitive processes, rather than deliberate reasoning. One of those intuitions appears to be physical purity, because it has a strong connection to moral purity.

[In experiment 1 two different groups of participants look at lists of scrambled words before being asked to rate the wrongness of six different moral dilemmas. Half of the words in one of the lists related to the theme of cleanliness and purity (e.g., pure, washed, clean, immaculate, pristine), while the other list contained neutral words. In experiment 2 participants were given an opportunity to physically cleanse themselves after experiencing disgust (a physically disgusting scene from a film).]

Heaven for the Godless?

A piece from Charles M. Blow:

In June, the Pew Forum on Religion and Public Life published a controversial survey in which 70 percent of Americans said that they believed religions other than theirs could lead to eternal life...This threw evangelicals into a tizzy. After all, the Bible makes it clear that heaven is a velvet-roped V.I.P. area reserved for Christians. Jesus said so: “I am the way, the truth and the life: no man cometh unto the Father, but by me.” But the survey suggested that Americans just weren’t buying that...The evangelicals complained that people must not have understood the question. The respondents couldn’t actually believe what they were saying, could they?

So in August, Pew asked the question again. (They released the results last week.) Sixty-five percent of respondents said — again — that other religions could lead to eternal life. But this time, to clear up any confusion, Pew asked them to specify which religions. The respondents essentially said all of them...And they didn’t stop there. Nearly half also thought that atheists could go to heaven — dragged there kicking and screaming, no doubt — and most thought that people with no religious faith also could go.

What on earth does this mean?

One very plausible explanation is that Americans just want good things to come to good people, regardless of their faith.

Rapid perceptual switching...

Jackson et al. examine contradictory perceptions while viewing biological versus moving ambiguous structures. (Try this movie of an ambiguous rotating walker, a figure that randomly alternates between walking in clockwise (CW) and counter-clockwise (CCW) directions.) Percept durations with a light point rotating walker are shorter than for a standard light point walker.

Brain lesions and sprituality

Johnstone and Glass note a correlation between increased spirituality and right parietal lobe lesions, more clear than previously noted correlations with left temporal lobe activity. They suggest this might arise from decreased awareness of the self (leading to sense of transcendence), while reports of spirituality and increased activity of the left temporal lobe might be associated with the experience of specific religious archetypes (religious figures and symbols). (If you click on 'religion' in the left column under 'selected blog categories' you will note a number of differing observations on correlations between spirituality and brain activity.)

Recent research suggests that spiritual experiences are related to increased physiological activity of the frontal and temporal lobes and decreased activity of the right parietal lobe. The current study determined if similar relationships exist between self-reported spirituality and neuropsychological abilities associated with those cerebral structures for persons with traumatic brain injury (TBI). Participants included 26 adults with TBI referred for neuropsychological assessment. Measures included the Core Index of Spirituality (INSPIRIT); neuropsychological indices of cerebral structures: temporal lobes (Wechsler Memory Scale-III), right parietal lobe (Judgment of Line Orientation), and frontal lobes (Trail Making Test, Controlled Oral Word Association Test). As hypothesized, spirituality was significantly negatively correlated with a measure of right parietal lobe functioning and positively correlated (nonsignificantly) with measures of left temporal lobe functioning. Contrary to hypotheses, correlations between spirituality and measures of frontal lobe functioning were zero or negative (and nonsignificant). The data support a neuropsychological model that proposes that spiritual experiences are related to decreased activity of the right parietal lobe, which may be associated with decreased awareness of the self (transcendence) and increased activity of the left temporal lobe, which may be associated with the experience of specific religious archetypes (religious figures and symbols).

Living the Off-Label Life

Further comments on cognition enhancing drugs from Warner, commenting on the Nature essay I mentioned previously.

Genetics of successful placebo response to stress.

Here is a fascinating piece of work from Furmark et al., showing that placebo treatment of stress in subjects with social anxiety disorder (reflected by reducted amygdala activity during public speaking) was successful only in individuals with particular forms of serotonin transporter and tryptophan hydroxylase genes. This demonstrates a link between genetically controlled serotonergic modulation of amygdala activity and placebo-induced anxiety relief. The experiments were done in the context of a study evaluating a potential anti-anxiety drug and matching placebo provided by GlaxoSmithKline.

Placebo may yield beneficial effects that are indistinguishable from those of active medication, but the factors underlying proneness to respond to placebo are widely unknown. Here, we used functional neuroimaging to examine neural correlates of anxiety reduction resulting from sustained placebo treatment under randomized double-blind conditions, in patients with social anxiety disorder. Brain activity was assessed during a stressful public speaking task by means of positron emission tomography before and after an 8 week treatment period. Patients were genotyped with respect to the serotonin transporter-linked polymorphic region (5-HTTLPR) and the G-703T polymorphism in the tryptophan hydroxylase-2 (TPH2) gene promoter. Results showed that placebo response was accompanied by reduced stress-related activity in the amygdala, a brain region crucial for emotional processing. However, attenuated amygdala activity was demonstrable only in subjects who were homozygous for the long allele of the 5-HTTLPR or the G variant of the TPH2 G-703T polymorphism, and not in carriers of short or T alleles. Moreover, the TPH2 polymorphism was a significant predictor of clinical placebo response, homozygosity for the G allele being associated with greater improvement in anxiety symptoms. Path analysis supported that the genetic effect on symptomatic improvement with placebo is mediated by its effect on amygdala activity. Hence, our study shows, for the first time, evidence of a link between genetically controlled serotonergic modulation of amygdala activity and placebo-induced anxiety relief.

Upper limb amputees can sense a rubber hand as their own

A further observation on the brain plasticity shown during the rubber hand illusion (mentioned in the Dec. 24 posting) is made by Ehrsson et al., who find that the illusion can induced in upper limb amputees:

We describe how upper limb amputees can be made to experience a rubber hand as part of their own body. This was accomplished by applying synchronous touches to the stump, which was out of view, and to the index finger of a rubber hand, placed in full view (26 cm medial to the stump). This elicited an illusion of sensing touch on the artificial hand, rather than on the stump and a feeling of ownership of the rubber hand developed. This effect was supported by quantitative subjective reports in the form of questionnaires, behavioural data in the form of misreaching in a pointing task when asked to localize the position of the touch, and physiological evidence obtained by skin conductance responses when threatening the hand prosthesis. Our findings outline a simple method for transferring tactile sensations from the stump to a prosthetic limb by tricking the brain, thereby making an important contribution to the field of neuroprosthetics where a major goal is to develop artificial limbs that feel like a real parts of the body.

Musing on the topic of well-being or happiness...

On seeing this Op-Ed piece by Lyubomirsky in the NYTimes I realized that this is the author, an academic researcher, who has put out a book that I am currently scanning titled "The How of Happiness: A Scientific Approach to Getting the Life You Want." The NYTimes Op-Ed piece notes that the reason that most of us are not more dejected than one might expect by the market meltdown and recession is that the fortunes of virtually everyone have been compromised, and we care more about social comparison, status and rank than about the absolute value of our bank accounts or reputations.

With regard to the book, Ms. Lyubomirsky can not be accused of being a skilled prose stylist, but her writing does offer a meat and potatoes list of behavioral tips on activities that have been shown in double blind studies on fairly large groups of real people to enhance well-being, namely:

Expressing gratitude
Cultivating Optimism
Avoiding over thinking and social comparison
Practicing acts of kindness
Nurturing relationships
Developing strategies for coping.
Learning to forgive
Doing more activities that truly engage you.
Savoring Life’s joys
Committing to your goals
Practicing religion and spirituality
Taking care of your body.

She suggests taking the four of these that seem most congenial to you, and working on those rather than tackling the whole list.

My take on this well-being stuff is that it does boil down to some fairly discrete mental operations, being a matter of executive (frontal lobe) function - to put some things in your mind and not others - images of coherence and well being versus random input from the environment and the old pandora’s box of your past. This is essentially cognitive therapy, letting one thing express rather than another (making a distinction such as: ‘this is a part of my brain that is not working to my advantage’). It does not have to be an energy draining self-coercion of one part of ourselves going to war with another, but rather is a self choosing of one option over another. You are what you spend your time doing.

Hemispheric shift of categorical color perception during brain development.

Franklin et al. show an interesting shift in categorical perception of colors from right to left hemisphere as infants learn the words that distinguish the relevant category boundaries, showing an influence of language on the functional organization of the brain.

Categorical perception (CP) of color is the faster and more accurate discrimination of two colors from different categories than two colors from the same category, even when same- and different-category chromatic separations are equated. In adults, color CP is lateralized to the left hemisphere (LH), whereas in infants, it is lateralized to the right hemisphere (RH). There is evidence that the LH bias in color CP in adults is due to the influence of color terms in the LH. Here we show that the RH to LH switch in color CP occurs when the words that distinguish the relevant category boundary are learned. A colored target was shown in either the left- or right-visual field on either the same- or different-category background, with equal hue separation for both conditions. The time to initiate an eye movement toward the target from central fixation at target onset was recorded. Color naming and comprehension was assessed. Toddlers were faster at detecting targets on different- than same-category backgrounds and the extent of CP did not vary with level of color term knowledge. However, for toddlers who knew the relevant color terms, the category effect was found only for targets in the RVF (LH), whereas for toddlers learning the color terms, the category effect was found only for targets in the LVF (RH). The findings suggest that lateralization of color CP changes with color term acquisition, and provide evidence for the influence of language on the functional organization of the brain.

Sharing today's New York Times

How social status shapes race.

Penner and Saperstein carry out an interesting analysis of data from the National Longitudinal Survey of Youth (NLSY), which contains multiple measures of interviewer-classified and self-identified race over a twenty-year period. Their abstract, followed by one figure from the paper:

We show that racial perceptions are fluid; how individuals perceive their own race and how they are perceived by others depends in part on their social position. Using longitudinal data from a representative sample of Americans, we find that individuals who are unemployed, incarcerated, or impoverished are more likely to be seen and identify as black and less likely to be seen and identify as white, regardless of how they were classified or identified previously. This is consistent with the view that race is not a fixed individual attribute, but rather a changeable marker of status.


Figure - Racial self-identification and cumulative social status, 2002. Source: National Longitudinal Survey of Youth. (A) The percentage of respondents who self-identified as white in 2002, restricted to respondents who identified as white in 1979. (B) The percentage of respondents who identified as black in 2002, restricted to respondents who identified as black in 1979. Ever-incarcerated refers to whether the respondent was ever interviewed while in prison; ever-unemployed refers to whether the respondent was ever unemployed for more than 4 months in a calendar year; and ever-impoverished refers to whether the respondent's household income was ever below the poverty line. Error bars, ± 1SE.

Altering our self-face recognition

In the wake of several recent posts on the rubber hand illusion, which alters our sense of where our hand is in space, I thought this observation by Tsakiris was interesting: multisensory input to our face (Synchronous tactile stimulation while watching another person's face being similarly touched) causes a bias in recognizing our own face. Here is the abstract:

How do I know the person I see in the mirror is really me? Is it because I know the person simply looks like me, or is it because the mirror reflection moves when I move, and I see it being touched when I feel touch myself? Studies of face-recognition suggest that visual recognition of stored visual features inform self-face recognition. In contrast, body-recognition studies conclude that multisensory integration is the main cue to selfhood. The present study investigates for the first time the specific contribution of current multisensory input for self-face recognition. Participants were stroked on their face while they were looking at a morphed face being touched in synchrony or asynchrony. Before and after the visuo-tactile stimulation participants performed a self-recognition task. The results show that multisensory signals have a significant effect on self-face recognition. Synchronous tactile stimulation while watching another person's face being similarly touched produced a bias in recognizing one's own face, in the direction of the other person included in the representation of one's own face. Multisensory integration can update cognitive representations of one's body, such as the sense of ownership. The present study extends this converging evidence by showing that the correlation of synchronous multisensory signals also updates the representation of one's face. The face is a key feature of our identity, but at the same time is a source of rich multisensory experiences used to maintain or update self-representations.

The net generation

Hurt offers a review of Tapscott's recent book "Growing up Digital", which defines the 81 million people born between 1977 to 1997 that make up 27% of the population as the "net generation" (following generations X and Y).

"As the first global generation ever, the Net Geners are smarter, quicker and more tolerant of diversity than their predecessors,” Tapscott writes. “They care strongly about justice and the problems faced by their society and are typically engaged in some kind of civic activity at school, at work or in their communities."

Mr. Tapscott devotes an entire chapter to examining how Net Geners are already using their collective power to transform society — as evidenced by their impact on Barack Obama’s presidential campaign...He documents how Mr. Obama capitalized on interactive social networking sites like Facebook and MySpace that inspired the participation of millions of small donors, while Hillary Rodham Clinton relied on relatively old broadcast-style media like television and e-mail to attract much lower numbers of mostly large donors.

Mr. Tapscott identifies eight norms of many members of the Net Generation: they prize freedom; they want to customize things; they enjoy collaboration; they scrutinize everything; they insist on integrity in institutions and corporations; they want to have fun even at school or work; they believe that speed in technology and all else is normal; and they regard constant innovation as a fact of life.

He cites recent brain-imaging and childhood-development studies to buttress his contention that Internet use by Net Geners has fundamentally changed — and improved — the way their brains are wired. Noting that raw I.Q. scores have been climbing by three points a decade since World War II across racial, income and regional boundaries, Mr. Tapscott asserts that Net Geners are also developing valuable skills that do not show up on standard I.Q. tests.

“Not only do video game players notice more, they have highly developed spatial skills that are useful for architects, engineers and surgeons,” he says.

Men are red, women are green.

Here is a curious bit which I pass on from the Random Samples section of the Dec. 19 Science Magazine, describing the work of researchers at Brown University:

Men are colored like Mars, but women are greenish--and the difference may help explain how people perceive la difference...Cognitive scientist Michael Tarr and grad student Adrian Nestor made the discovery by averaging mug shots of 200 white males and females into a single androgynous face. They then obscured it further with randomly placed red and green pixels.

Three volunteers looked at 20,000 different versions of the image--some redder, others greener--and told the researchers which sex they thought each face represented. The result: Faces with green pixels were tagged as female and those with more red pixels as male. The color of the cheekbones, nose, and sides of the mouth were particularly important to decisions, says Tarr, whose paper is in press in Psychological Science.

Marlene Behrmann, a psychologist at Carnegie Mellon University in Pittsburgh, Pennsylvania, says the fact that people subconsciously recognize the red-green distinction "means there is something evolutionarily and ecologically important about color that extends even into the human central nervous system."

Bach oratorio on period instruments.

Cognitive benefits of a walk in the woods

An article by Berman et al. in Psychological Science (PDF here) shows that immersion in a natural environment leads to more than simply a sense of feeling refreshed, it also recharges our cognitive batteries:

We compare the restorative effects on cognitive functioning of interactions with natural versus urban environments. Attention restoration theory (ART) provides an analysis of the kinds of environments that lead to improvements in directed-attention abilities. Nature, which is filled with intriguing stimuli, modestly grabs attention in a bottom-up fashion, allowing top-down directed-attention abilities a chance to replenish. Unlike natural environments, urban environments are filled with stimulation that captures attention dramatically and additionally requires directed attention (e.g., to avoid being hit by a car), making them less restorative. We present two experiments that show that walking in nature or viewing pictures of nature can improve directed-attention abilities as measured with a backwards digit-span task and the Attention Network Task, thus validating attention restoration theory.

Seasonal Nostalgia

I alternatively want to feel warm and cushy or gag myself with a spoon on watching this.

Knowing where and knowing how to get there - a dissociation in the rubber hand illusion.

Kammers et al. show that during the rubber hand illusion (in which watching a rubber hand being stroked while our own unseen hand is synchronously stroked induces a relocation of the sensed position of our own hand towards the rubber hand) our actual ballistic hand movements resist the illusion. Their abstract contains some useful references:

In the well-known rubber hand illusion (RHI), watching a rubber hand being stroked while one's own unseen hand is synchronously stroked, induces a relocation of the sensed position of one's own hand towards the rubber hand [Botvinick, M., & Cohen, J. (1998). Rubber hands ‘feel’ touch that eyes see. Nature, 391(6669), 756]. As one has lost the veridical location of one's hand, one should not be able to correctly guide one's hand movements. An accurate representation of the location of body parts is indeed a necessary pre-requisite for any correct motor command [Graziano, M. S. A., & Botvinick, M. M. (1999). How the brain represents the body: Insights from neurophysiology and psychology. In D. Gopher, & A. Koriat (Eds.), Attention and performance XVII—Cognitive regulation of performance interaction of theory and application (pp. 136–157)]. However, it has not yet been investigated whether action is indeed affected by the proprioceptive drift towards the rubber hand, nor has the resistance of visual capture in the RHI to new proprioceptive information been assessed. In the present two kinematic experiments, we show for the first time that action resists the RHI and that the RHI resists action. In other words, we show a dissociation between illusion-insensitive ballistic motor responses and illusion-sensitive perceptual bodily judgments. Moreover, the stimulated hand was judged closer to the rubber hand for the perceptual responses, even after active movements. This challenges the view that any proprioceptive update through active movement of the stimulated hand erases the illusion. These results expand the knowledge about representations of the body in the healthy brain, and are in line with the currently most used dissociation between two types of body representations so far mainly based on neuropsychological patients [Paillard, J. (1991). Knowing where and knowing how to get there. In J. Paillard (Ed.), Brain and space (pp. 461–481); Paillard, J. (1999). Body schema and body image: A double dissociation in deafferented patients. In G. N. Gantchev, S. Mori, & J.Massion (Eds.), Motor control, today and tomorrow (pp. 197–214)].

Effect of candidate appearance on election outcomes - neural correlates

An interesting open access article from Adolphs and collaborators:

Election outcomes correlate with judgments based on a candidate's visual appearance, suggesting that the attributions viewers make based on appearance, so-called thin-slice judgments, influence voting. Yet, it is not known whether the effect of appearance on voting is more strongly influenced by positive or negative attributions, nor which neural mechanisms subserve this effect. We conducted two independent brain imaging studies to address this question. In Study 1, images of losing candidates elicited greater activation in the insula and ventral anterior cingulate than images of winning candidates. Winning candidates elicited no differential activation at all. This suggests that negative attributions from appearance exert greater influence on voting than do positive. We further tested this hypothesis in Study 2 by asking a separate group of participants to judge which unfamiliar candidate in a pair looked more attractive, competent, deceitful and threatening. When negative attribution processing was enhanced (specifically, under judgment of threat), images of losing candidates again elicited greater activation in the insula and ventral anterior cingulate. Together, these findings support the view that negative attributions play a critical role in mediating the effects of appearance on voter decisions, an effect that may be of special importance when other information is absent.

Enhanced perception of threat during limited attention

This open access article from Dolan's and collaborators builds on previous studies on the role of the amygdala in pre-attentive processing of potential threats, noting parts of the brain that become active during threat identification during periods of compromised attention. Their abstract:

The ability to process stimuli that convey potential threat, under conditions of limited attentional resources, confers adaptive advantages. This study examined the neurobiology underpinnings of this capacity. Employing an attentional blink paradigm, in conjunction with functional magnetic resonance imaging, we manipulated the salience of the second of 2 face target stimuli (T2), by varying emotionality. Behaviorally, fearful T2 faces were identified significantly more than neutral faces. Activity in fusiform face area increased with correct identification of T2 faces. Enhanced activity in rostral anterior cingulate cortex (rACC) accounted for the benefit in detection of fearful stimuli reflected in a significant interaction between target valence and correct identification. Thus, under conditions of limited attention resources activation in rACC correlated with enhanced processing of emotional stimuli. We suggest that these data support a model in which a prefrontal "gate" mechanism controls conscious access of emotional information under conditions of limited attentional resources.

In the same issue of Cerebral Cortex, another Dolan collaboration uses a masked face priming paradigm to show that face responsive regions of the brain become active in the absence of awareness of faces that are presented.

Our motor cortex responds to musical rhythms.

From Chen et al. :

Perception and actions can be tightly coupled; but does a perceptual event dissociated from action processes still engage the motor system? We conducted 2 functional magnetic resonance imaging studies involving rhythm perception and production to address this question. In experiment 1, on each trial subjects 1st listened in anticipation of tapping, and then tapped along with musical rhythms. Recruitment of the supplementary motor area, mid-premotor cortex (PMC), and cerebellum was observed during listen with anticipation. To test whether this activation was related to motor planning or rehearsal, in experiment 2 subjects naively listened to rhythms without foreknowledge that they would later tap along with them. Yet, the same motor regions were engaged despite no action–perception connection. In contrast, the ventral PMC was only recruited during action and action-coupled perceptual processes, whereas the dorsal part was only sensitive to the selection of actions based on higher-order rules of temporal organization. These functional dissociations shed light on the nature of action–perception processes and suggest an inherent link between auditory and motor systems in the context of rhythm.

Video Introduction to Experimental Philosophy

A MindBlog reader points us to this site, which uses a a YouTube video to better explain the concept of intention and the role our moral judgments play in our perception of intent.

Avian Dancing

From the New York Times Magazine special issue on 'Year in Ideas 2008', slightly edited:

Here you see a large white bird balanced on the back of an office chair, bobbing his head, stomping his feet and ... dancing just like a human. Snowball’s videos are changing the way researchers understand the neurology of music and dancing.

Aniruddh Patel, senior fellow at the Neurosciences Institute in California, got the link from a friend. He saw not just a funny bird but also a potential solution to a scientific argument dating back to Darwin: some researchers say that human brains have been specially wired by natural selection for dancing, because dancing confers survival benefits through group bonding. If that were true, according to Patel, you would see dancing only in animals that, like humans, have a long history of music and dance, which no other species has. The fact that only humans dance has long been seen as evidence supporting the evolution argument.

So Patel sent an e-mail message to Snowball’s owner, Irena Schulz, and asked to study her bird. “The obvious question was whether he was just mimicking somebody,” Patel said. To answer that, he made CDs of Snowball’s favorite song (“Everybody (Backstreet’s Back)” by the Backstreet Boys) at various speeds. Schulz videotaped Snowball dancing to each version, and then Patel graphed Snowball’s movement against the music’s beat. “Like a child, he synched to the music for stretches of time, then danced a little faster or a little slower, but always in a rhythmic way,” Patel says. “Statistically those periods when he’s locked onto the beat are not by chance — they really do indicate sensitivity to the beat and an ability to synchronize with it.”

What’s most interesting to Patel is that this ability is present in birds but not in primates, our closest animal relatives. “This is no coincidence,” he says. Patel says dancing is associated with our vocal abilities, not musical hard wiring. Humans and parrots are two of the few species with brains wired for vocal learning — hearing sounds (like words), then coordinating complex movements (lips, tongues, vocal cords) to reproduce those sounds. Other animals who have this ability: dolphins, seals and whales. “In theory,” he says, “they may be able to dance, too. We just don’t know it yet.”

Crisis of Confidence for Masters of the Universe

An interesting article by Friedman in the NYTimes on psychological effects of the market meltdown.

Over the last few months, I have seen a group of patients, all men, who experienced a near collapse in their self-esteem, though none of them were clinically depressed...
Another patient summed it up: “I used to be a master-of-the-universe kind of guy, but this cut me down to size.”

I have plenty of female patients who work in finance at high levels, but none of them has had this kind of psychological reaction. I can’t pretend this is a scientific survey, but I wonder if men are more likely than women to respond this way. At the risk of trading in gender stereotypes, do men rely disproportionately more on their work for their self-esteem than women do? Or are they just more vulnerable to the inevitable narcissistic injury that comes with performing poorly or losing one’s job?

A different patient was puzzled not by his anxiety about the market, but by his total lack of self-confidence. He had always had an easy intuitive feel for finance. But in the wake of the market collapse, he seriously questioned his knowledge and skill.

On Wall Street, though, a rising tide lifts many boats and vice versa, which means that there are many people who succeed — or fail — through no merit or fault of their own.

This observation might ease a sense of personal responsibility for the economic crisis, but it was of little comfort to my patients. I think this is because for many of them, the previously expanding market gave them a sense of power along with something as strong as a drug: thrill.

The human brain is acutely attuned to rewards like money, sex and drugs. It turns out that the way a reward is delivered has an enormous impact on its strength. Unpredictable rewards produce much larger signals in the brain’s reward circuit than anticipated ones. Your reaction to situations that are either better or worse than expected is generally stronger to those you can predict.

My patients lost more than money in the market. Beyond the rush and excitement, they lost their sense of competence and success. At least temporarily: I have no doubt that, like the economy, they will recover. But it’s a reminder of just how fragile our self-confidence can be.

Why are we so nice? ...because generosity wins.

Here is a further entry in Nature's "Being Human" series, in which Martin Nowak points out that mathematical models predict, and experiments confirm, that generosity is an essential feature of winning strategies in games that explore human interactions. 'Prosocial behaviour' has evolved within a framework of direct or indirect reciprocity, and the latter may have provided selection pressure for social intelligence and language. A few excerpts:

Only if certain mechanisms are involved can natural selection favour individuals who reduce their own fitness to increase that of a competitor. One such mechanism is direct reciprocity: my strategy depends on what you have done to me. Another is indirect reciprocity: my strategy depends on what you have done to me and on what you have done to others.

In both, mathematical analysis shows that winning strategies tend to be generous, hopeful and forgiving. Generous here means not seeking to get more than one's opponent; hopeful means cooperating in the first move or in the absence of information; and forgiving means attempting to re-establish cooperation after an accidental defection. These three traits are related. If I am generous, it is easier for me to forgive, and also to be hopeful and take the risk of cooperating with newcomers.

Experiments have confirmed the success of generosity. A typical set-up involves students and computer screens. The computer pairs random individuals. One person, the donor, is asked if she wishes to transfer some money to the recipient. She is informed about the recipient's decisions in previous rounds with other players. The experiment shows that people base their decision on what the recipient has done before. Generous people are more likely to receive donations.

Similar reputation-based systems operate in e-commerce. When buying a camera online, you might consider both the price and the seller's reputation. Consumers are willing to pay higher prices if the seller is thought to be reliable. Successful websites are those with good reputations.

So why aren't humans always 'generous, hopeful and forgiving'? Part of the explanation may be that cooperation is never a stable state. Mathematical studies show that it is constantly challenged by defection. In a society of defectors where no-one helps, a cluster of cooperating individuals can emerge if, by chance, a few people start playing a direct reciprocity strategy called tit-for-tat: I do whatever you have done to me. Tit-for-tat can't persist for long because its appetite for revenge is self-destructive. It is soon replaced by 'generous tit-for-tat'. Here, I cooperate whenever you have cooperated, but sometimes even when you have defected. In other words, I am forgiving. For a while, cooperation thrives. But in a generous tit-for-tat population, the emergence of unconditional cooperators eventually invites the invasion of defectors. This leads to cycles of cooperation and defection — which could account, at least in part, for the mix of cooperators and defectors that persists in human societies.

Mathematical models allow a precise investigation of fundamental aspects of human behaviour. The games described here occur in every society. Ancestral humans spent most of their time in small groups where interactions were repeated. The same is true for most dealings in modern life: repeat encounters are always possible and reputation is typically at stake. The evolution of prosocial behaviour cannot be understood outside the framework of direct or indirect reciprocity. Indeed, I believe that games of indirect reciprocity have provided the crucial selection pressures for social intelligence and language.

In such games, social intelligence is needed to monitor and interpret the interactions of others. We follow with great interest what our fellow creatures do to us and to others. When deciding how to act, we take into account — often subconsciously — the possible consequences for our own reputation. Moreover, our own observations are often not enough; we want to learn from the experiences of others. Spreading the rumours of indirect reciprocity requires language. As my colleague David Haig once remarked "for direct reciprocity you need a face, for indirect reciprocity you need a name".

Wheel of life.

I recently came across this interesting graphic demonstration of the Buddha's wheel of life, narrated by Robert Thurman.

How a cognition enhancing drug works.

Minzenberg et. al. find that brain images of humans treated with a cognitive enhancing drug show increased task-oriented activity in a brainstem nucleus and confirm that this region controls cognition. Their abstract:

Models of cognitive control posit a key modulatory role for the pontine locus coeruleus–norepinephrine (LC-NE) system. In nonhuman primates, phasic LC-NE activity confers adaptive adjustments in cortical gain in task-relevant brain networks, and in performance, on a trial-by-trial basis. This model has remained untested in humans. We used the pharmacological agent modafinil to promote low-tonic/high-phasic LC-NE activity in healthy humans performing a cognitive control task during event-related functional magnetic resonance imaging (fMRI). Modafanil administration was associated with decreased task-independent, tonic LC activity, increased task-related LC and prefrontal cortex (PFC) activity, and enhanced LC-PFC functional connectivity. These results confirm in humans the role of the LC-NE system in PFC function and cognitive control and suggest a mechanism for therapeutic action of procognitive noradrenergic agents.

Advocacy of cognition enhancing drugs.

Stimulants such as methyl-phenidate (Ritalin) and modafinil (Provigil), familiar as treatments for attention deficit hyperactivity disorder and narcolepsy respectively, are increasingly used as 'smart drugs' by students and more widely as a boost to intellectual creativity. Should society recognize the demand for cognitive enhancement? The trend has been resisted by some on the grounds of safety, 'medicalization' and social inequality. Urging responsible use of cognitive-enhancing drugs by the healthy, Greely et al., in an open access article, think that society must respond to the growing demand for cognitive enhancement. A few clips from their article:

Ritalin (methyphenidate) and Adderall (mixed amphetamine salts), and are prescribed mainly for the treatment of attention deficit hyperactivity disorder (ADHD). Because of their effects on the catecholamine system, these drugs increase executive functions in patients and most healthy normal people, improving their abilities to focus their attention, manipulate information in working memory and flexibly control their responses...A newer drug, modafinil (Provigil), has also shown enhancement potential. Modafinil is approved for the treatment of fatigue caused by narcolepsy, sleep apnoea and shift-work sleep disorder....laboratory studies have shown that modafinil enhances aspects of executive function in rested healthy adults, particularly inhibitory control.

Many people have doubts about the moral status of enhancement drugs for reasons ranging from the pragmatic to the philosophical, including concerns about short-circuiting personal agency and undermining the value of human effort. Kass, for example, has written of the subtle but, in his view, important differences between human enhancement through biotechnology and through more traditional means. Such arguments have been persuasively rejected. Three arguments against the use of cognitive enhancement by the healthy quickly bubble to the surface in most discussions: that it is cheating, that it is unnatural and that it amounts to drug abuse.

In the context of sports, pharmacological performance enhancement is indeed cheating. But, of course, it is cheating because it is against the rules. Any good set of rules would need to distinguish today's allowed cognitive enhancements, from private tutors to double espressos, from the newer methods, if they are to be banned.

As for an appeal to the 'natural', the lives of almost all living humans are deeply unnatural; our homes, our clothes and our food — to say nothing of the medical care we enjoy — bear little relation to our species' 'natural' state. Given the many cognitive-enhancing tools we accept already, from writing to laptop computers, why draw the line here and say, thus far but no further?

Like all new technologies, cognitive enhancement can be used well or poorly. We should welcome new methods of improving our brain function. In a world in which human workspans and lifespans are increasing, cognitive enhancement tools — including the pharmacological — will be increasingly useful for improved quality of life and extended work productivity, as well as to stave off normal and pathological age-related cognitive declines. Safe and effective cognitive enhancers will benefit both the individual and society.

But it would also be foolish to ignore problems that such use of drugs could create or exacerbate. With this, as with other technologies, we need to think and work hard to maximize its benefits and minimize its harms.

This is so kewl.....

From Science Magazine's 'Random Samples' feature:

Meet the Pivo 2, Nissan's compact electric concept car, designed for urban travel with a 360° rotating cabin and wheels that allow the car to scoot sideways for parking. It's one of the stars of the new exhibit "Japan Car: Designs for the Crowded Globe" at London's Science Museum, spotlighting "mobile cells"--small cars fueled by low-polluting electricity or hydrogen and equipped with intelligent driver interfaces.

Other examples include Toyota's iREAL, a sitting version of a Segway that looks like a futuristic wheelchair, with sensors that alert a driver to obstacles down the road, and Mitsubishi's electrical iMiEV, planned for release next year, that can go 160 kilometers on an overnight charge.

Key features of these vehicles are their brains. Pivo 2 has a talking "robotic agent" that offers traffic updates and route information and has voice-recognition capability to answer a driver's questions. The agent is personified by a swiveling head mounted beside the instrument panel that nods and shakes to keep the driver in a "positive frame of mind." "It infers the driver's mood through conversation and facial-monitoring technology," Nissan says. But can you make it shut up? Nissan doesn't say.

Crazy Money

An article by Chelsea Wald continues to make the case that financial theories can not assume that investor behavior is rational. Some clips from that article:

Even the experts seem bewildered by the current economic crisis. Quantitative analysts (quants)--the whiz-kid financial engineers whose algorithms have dominated Wall Street trading in recent years--have watched those algorithms fail. Former Federal Reserve Chair Alan Greenspan acknowledged in October that there was "a flaw in the model that I perceived … defines how the world works."...the classical theory of finance simply does not address human psychology. It looks more like a physical science than a social science--relying on the premises that markets are "efficient,"

Blame has fallen on quants for various aspects of the crisis. First, mathematical models were increasingly used to determine whether someone deserved a loan, bypassing individual judgments. "In the end, there was very little sound credit judgment going into making these credit calls," says Bjorn Flesaker, a senior quant at Bloomberg in New York. Then, quant models were used to rate the riskiness of financial instruments, including the CDOs. "We never necessarily viewed the rating agencies as having the greatest rocket scientists around," says Flesaker, yet investors accepted those ratings, taking on more risk than even they realized...like many of the elements that economists and the media have focused on, the quant models are simply "proximate causes." Ultimately, experts must examine human behavior to find out why the crisis happened. Why did so many people take on mortgages that they would not be able to pay? Why did the best minds of Wall Street ignore warnings about a housing bubble? "The bottom-line question that economists, I think, still are struggling with is: 'Did anybody know that the risks were so great and, if so, why did they continue investing?'

The madness of crowds

Classical finance theory's model of speculative bubbles, such as the dot-com bubble of the late '90s and the recent housing bubble, does not match real-life observations. Classical finance contends that rational investors will always have the best possible portfolio, so they will not buy or sell unless they have extra money to invest or need to cash in their investments. However, researchers have observed that people buy and sell much more often than that during a bubble--with the rate of transactions becoming increasingly manic the bigger the bubble gets.

Lacking a good classical model for stock-market bubbles, Scheinkman, whose work is primarily classical, turned to a concept in behavioral finance. Psychologists have found that people often overestimate the precision of their knowledge. Scheinkman and his Princeton colleague Wei Xiong guessed that overconfident investors would trust their own opinions about the price of an asset, so they would consider others' opinions, if different, a little "crazy," says Scheinkman. Looking to make money off others' crazy opinions, investors would be willing to pay more than they think an asset is actually worth because they believe that they will be able to sell it in the future to an overeager buyer. This process would inflate prices and cause a trading frenzy. Incorporating investor overconfidence into a theoretical model published in 2003 in the Journal of Political Economy, Scheinkman and Xiong were able to recreate more accurately the hyperactive trading in bubbles.

Andrew Lo, a financial economist at MIT, is developing alternative models:

Lo's species behave differently based on what part of their brains they are using. When things go well and people make money, as they did for the past decade, the experience stimulates investors' reward circuitry. This causes them to seek more profits and ignore possible risk, leading, for example, to a bubble. When things take a turn for the worse, panic overrides rational decision-making, leading to a crash. Only when the market is steady does the rational brain take over. Lo is starting to use functional magnetic resonance imaging and other tools of neuroscience to quantify these behaviors and incorporate them into his models. He also needs more real-world data on the way different funds invest money--data that are now secret or that no one bothers to collect.

Although Lo's idiosyncratic approach lies outside of the behavioral and classical theories, he says it reconciles them. "If you were an efficient-markets type, I think you'd be hard-pressed to explain what happened over the last few weeks. And if you were an irrational finance person, you'd be hard-pressed to explain what happened over the previous 10 years. So I think that the only way to reconcile the two is to acknowledge that both are different aspects of the exact same truth."

Behavioral researchers are eager to prove that their ideas mirror nature by using quantitative methods to link them directly to real-life data... Stock pricing lends itself to such studies, because valuing a stock involves conjecture--which is subject to psychological factors--and a lot of stock-market data have recently become available to academic researchers.

In a 2007 paper in the Journal of Economic Perspectives, Wurgler and co-author Malcolm Baker, a financial economist at Harvard Business School, looked for signatures of investor sentiment--irrational optimism or pessimism--in stock-market data since the 1960s. They hypothesized that certain stocks would be more subject to sentiment than others: broadly speaking, stocks for which the true value is difficult to determine. For example, a young, promising company would fit the bill. "The combination of no earnings history and a highly uncertain future allows investors to defend valuations ranging from much too low to much too high," they write.

Comparing the stock-market data with their measure of investor sentiment, they found what they had expected. In optimistic times, difficult-to-value stocks were wildly popular and therefore made much more money than average. In pessimistic times, they were wildly unpopular and therefore made much less money than average. On the other hand, easy-to-value stocks, which are considered safer, were more popular in pessimistic times than optimistic ones, but their prices stayed much closer to average. This helps explain past bubbles in certain types of stocks--say, dot-com stocks in the 1990s--and is also useful for making predictions for the future

Conflict: Altruism's midwife

Bowles has an interesting article in the Nature "Being Human" series. From the editor's comments:

The historical and archaeological records reveal that humans became especially good at killing 'outsiders' from other groups, tribes or nations. Some animals do engage in such conflicts, but humans excel. We are also uniquely receptive to socialization and learning, and can achieve the heights of altruistic behaviour. Economist Samuel Bowles argues that these two extremes may be related: generosity and solidarity towards one's own may have emerged only in combination with hostility towards outsiders. Both may be part of what it is to be human. All essays in the 'Being human' series are available free via http://tinyurl.com/55ncjj.

From the article:

Among ancestral humans, parochial altruists may have provoked conflicts between groups over scarce natural and reproductive resources, and at the same time contributed to a group's success in these conflicts. Altruism would have facilitated the coordination of raiding and ambushing on a scale known in few other animals, while parochialism fuelled the antipathy towards outsiders. Additionally, with the development of projectile weapons, humans became adept at killing from a distance, which would have reduced the costs of aggression.

Support for this idea comes from artificial histories of early human evolution that my co-authors and I simulated by computer. In these simulations, we allowed groups of agents, tolerant or parochial, altruistic or selfish, to interact over thousands of generations under conditions likely to have been experienced by our Late Pleistocene and early Holocene ancestors. We designed the simulations so that violent conflict between two groups is likely if at least one group contains a preponderance of parochialists. We also made each group's fighters the parochial altruists (non-altruists are happy to let someone else do the fighting; tolerant members prefer to stay on friendly terms with outsiders). Thus, the groups with the most parochial altruists tend to win conflicts. Our objective was to see how the frequency of warfare, and the fraction of the different types of agent, would evolve.

In millions of simulated evolutionary histories, the populations emerging after thousands of generations of selection tend to be either tolerant and selfish, with little warfare, or parochial and altruistic with frequent and lethal encounters with other groups. Occasional transitions occur between the selfish peaceful states and the warring altruistic states. But neither altruism nor parochialism ever proliferate singly; they share a common fate, with war the elixir of their success.

Dogs have sense of fairness.

Fountain points to work by Range et al. showing that dogs, like monkeys and chips, have a sense of equity and fairness. A dog may stop obeying a command if it sees that another dog is getting a better deal. Thus, species other than primates show at least a primitive version of inequity aversion, perhaps a precursor of a more sophisticated sensitivity to efforts and payoffs of joint interactions.

I wonder if this behavior also might possibly be related to the extensive breeding selection carried out on dogs over the past several thousand years which has made them, unlike monkeys and apes, very attentive to human moods and intentions.

(Note: I usually compose these blog postings several days in advance of their actual appearance, to keep free of deadline pressure. The downside of this is that I frequently see something I want to mention appearing immediately on, for example, the Op-Ed page of the New York Times. This bit on fairness in dogs is referenced by Gail Collins as relevant to the current U.S. automakers bailout controversy.)

If I Were You: Perceptual Illusion of Body Swapping

The title of this post is also the title of a fascinating article published in PLoS ONE. When tricked by some simple optical and sensory illusions, we can adopt any other human form, no matter how different, as our own. From Carey's review:

The technique is simple. A subject stands or sits opposite the scientist, as if engaged in an interview. Both are wearing headsets, with special goggles, the scientist’s containing small film cameras. The goggles are rigged so the subject sees what the scientist sees: to the right and left are the scientist’s arms, and below is the scientist’s body...To add a physical element, the researchers have each person squeeze the other’s hand, as if in a handshake. Now the subject can see and “feel” the new body. In a matter of seconds, the illusion is complete. In a series of studies, using mannequins and stroking both bodies’ bellies simultaneously, the Karolinska researchers have found that men and women say they not only feel they have taken on the new body, but also unconsciously cringe when it is poked or threatened.

Here is the abstract from the article:

The concept of an individual swapping his or her body with that of another person has captured the imagination of writers and artists for decades. Although this topic has not been the subject of investigation in science, it exemplifies the fundamental question of why we have an ongoing experience of being located inside our bodies. Here we report a perceptual illusion of body-swapping that addresses directly this issue. Manipulation of the visual perspective, in combination with the receipt of correlated multisensory information from the body was sufficient to trigger the illusion that another person's body or an artificial body was one's own. This effect was so strong that people could experience being in another person's body when facing their own body and shaking hands with it. Our results are of fundamental importance because they identify the perceptual processes that produce the feeling of ownership of one's body.

I would love to try this...

My own personal helicopter.

Spread of Happiness - a network analysis.

A report by Fowler and Christakis, as noted by Belluck, is generating interest and controversy. In an analysis covering 20 years of the well known Framington Heart Study they find that happiness spreads like a contagion, that one's happiness is influence by the happiness of friends of friends. The issue is whether the study proved that people became happy because of their social contacts or some unrelated reason. In the same issue of the British Medical Journal, Cohen-Cole and Fletcher critique the work, showing that the statistical analysis used in network studies can detect implausible social network effects in acne, height, and headaches. Here is a summary graphic based on the work provided by the New York Times: