Wednesday, January 14, 2009

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.

Tuesday, January 13, 2009

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.

Monday, January 12, 2009

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.

Friday, January 09, 2009

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.

Thursday, January 08, 2009

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

Wednesday, January 07, 2009

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."

Tuesday, January 06, 2009

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.

Monday, January 05, 2009

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).]

Friday, January 02, 2009

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.

Thursday, January 01, 2009

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.