Steven Pinker explores The Genealogy Craze in America in TNR. He covers most of the angles, and expands a bit out from a laser-like focus on scientific genealogy toward the relevance of relatedness in the evolution of social behavior.

Religious concepts promote cooperation:

Participants primed with religious concepts gave their partner an average of $4.22, compared with only $1.84 in the control group. But those who declared themselves religious before the study were no more generous than non-believers.

“The effect of the religious prime was both large and surprising, especially considering that during exit interviews the participants were unaware of having been religiously primed,” says Shariff.

A second study introduced a third group, primed with words associated with civic responsibility such as “jury”, contract”, and “police.” This group behaved almost identically to that primed with religious concepts.

You can read the full working paper for free. There were two groups. One consisted of 50 UBC students, and the second a somewhat larger and more diverse group from the Vancouver, BC, area. The basic finding was that “priming” subjects with religious terms seemed to elevate generosity during an un-iterated Ultimatum Game, where the ‘rational actor’ should just keep all the money. In the first sample there wasn’t even a statistically significant difference between religious & irreligious students in how they reacted to the priming. The second study was more equivocal, and the authors in the discussion suggest that part of the reason that the irreligious tended to be less responsive toward religious priming was that the greater stringency of the test for ‘atheism’ filtered the individuals to a greater degree who were defined as non-religious, and a small number of subjects might simply even lack the implicit resonances of supernatural agents. Finally, the second study also showed that subjects could be primed toward generosity by exposing them to civic terminology.

First, the authors note the problems with their small and narrow sample sizes. Though statistically significant and powerful, the effects were derived from people from the Vancouver area, or, college students at UBC. I didn’t see controlling for the fact that there is likely some correlation between ethnicity and religion in British Columbia. Specifically, a disproportionate number of secular British Columbians are likely to be Chinese origin. Second, cognition expresses and develops within a cultural context. In a society with less civic engagement and activity than Canada I would not be surprised if the effect of secular priming was trivial. Similarly, in a society that is extremely secular (Japan?) one might see far greater response to civic priming than the supernatural equivalent. Third, the authors suggest that the response of theistic and non-theistic individuals in the first group to supernatural concepts suggests an implicit association between religious concepts and altruistic behavior. I have suggested myself that the anthropomorphic bias which is a pillar of religiosity exists in many, or all, atheists. Rejection of a deity might be sincere on the explicit level, but the implicit mind might still be strongly shaped by early cultural conditioning. The secular individuals in the UBC sample were no doubt aware of the valences and power of religious beliefs and ideas, and it seems plausible that lifetime implicit associations would have been built up.

Overall, this study is good because as the researchers point out there is a lot of armchair bullshitting on this topic. I get plenty of it in the comments of my weblogs. This study shows supernatural agents can act as mediators of human action as posited by many. It also shows that secular institutions and values can trigger the same change in behavior. What does this tell us on the fundamental level? I’m not sure, after all, the typical modern human has been exposed to several thousand years of philosophical religion which has embedded within it an explicit moral/ethical dimension. Similarly, bureaucratic government and the ideologies of mass societies are “in the air,” so to speak. In some “primitive” societies gods are seem as much more amoral creatures than in “advanced” cultures; they are mischievous agents who humans must placate and deceive. Additionally, they have no well developed theories of statecraft or a conception of law enforced by political fiat. It would be interesting to do this sort of study in a primitive society, though obviously the lack of literacy would cause problems with the priming the researchers used in this case.

Circumcision doesn’t reduce sensation: study:

The study, published in The Journal of Sexual Medicine, looked at a group of 40 men, half of them circumcised. Using sensory testing, the men were monitored at two points on the penis and the forearm while viewing erotic films. Thermal imaging was used to measure sexual arousal.

I think one can criticize this study on the relative coarseness of measure, after all, registering qualia is not a trivial task. Nevertheless, do note that in my previous comment on circumcision I did suggest that “pleasure” might be renormalized by the brain. Remember how good McDonald’s tasted when you are 8 years old?
Related: Circumcision & AIDS, Circumcision – human rights issue?, and Circumcision – HIV vs. pleasure?.

I did a poor job asking pubmed for the paper Razib mentioned earlier, but this surely does look interesting:

Brain pathology in pedophilic offenders: evidence of volume reduction in the right amygdala and related diencephalic structures.
Kolja Schiltz, Joachim Witzel, Georg Northoff, Kathrin Zierhut, Udo Gubka, Hermann Fellmann, Jörn Kaufmann, Claus Tempelmann, Christine Wiebking, Bernhard Bogerts

CONTEXT: Pedophilic crime causes considerable public concern, but no causative factor of pedophilia has yet been pinpointed. In the past, etiological theories postulated a major impact of the environment, but recent studies increasingly emphasize the role of neurobiological factors, as well. However, the role of alterations in brain structures that are crucial in the development of sexual behavior has not yet been systematically studied in pedophilic subjects. OBJECTIVE: To examine whether pedophilic perpetrators show structural neuronal deficits in brain regions that are critical for sexual behavior and how these deficits relate to criminological characteristics. DESIGN: Amygdalar volume and gray matter of related structures that are critical for sexual development were compared in 15 nonviolent male pedophilic perpetrators (forensic inpatients) and 15 controls using complementary morphometric analyses (voxel-based morphometry and volumetry). Psychosocial adjustment and sexual offenses were also assessed. RESULTS: Pedophilic perpetrators showed a significant decrease of right amygdalar volume, compared with healthy controls (P = .001). We observed reduced gray matter in the right amygdala, hypothalamus (bilaterally), septal regions, substantia innominata, and bed nucleus of the striae terminalis. In 8 of the 15 perpetrators, enlargement of the anterior temporal horn of the right lateral ventricle that adjoins the amygdala could be recognized by routine qualitative clinical assessment. Smaller right amygdalar volumes were correlated with the propensity to commit uniform pedophilic sexual offenses exclusively (P = .006) but not with age (P = .89). CONCLUSIONS: Pedophilic perpetrators show structural impairments of brain regions critical for sexual development. These impairments are not related to age, and their extent predicts how focused the scope of sexual offenses is on uniform pedophilic activity. Subtle defects of the right amygdala and closely related structures might be implicated in the pathogenesis of pedophilia and might possibly reflect developmental disturbances or environmental insults at critical periods

Razib recently mentioned a paper on a polymorphism regulating memory in Drosophila. As I often do when studies like these are published, I determined the human homologue of the gene in question (PRKG1, in this case), and checked out the plots of summary statistics available online. Sure enough, there are peaks in the significance of iHS, Tajima’s D, and Fay and Wu’s H in the area (all signs of recent selection), though strikingly these peaks are only evident in the Asian population. Hm.

Recently purchased a video iPod. I am the nerd sitting outside the coffeeshop groking brain network dynamics on my tiny screen. At least my case is stylish.

Here is a trove on that subject:
Conference on Brain Network Dynamics, 1/26/2007

That conference was in part a tribute to Walter Freeman. Here is more from him:
Poetry of Brains

Digging around more you can find several videos from the Redwood Center for Theoretical Neuroscience. For instance, Micro-circuits of Episodic Memory: Structure Matches Function in the Hippocampal System, and a debate entitled “Waves or words in cortex?” featuring Professor Freeman again.

On the mathy tip, you can download .mov’s on some pretty interesting topics from the Mathematical Sciences Research Institute. If someone can point me to a converter so I can carry them around with me I would be muy grateful. I’m more interested in the ones that seem to have some relation to biology such as Frances Tong on Normalization of Western Blots.

Speaking of .movs to convert. I found an extensive discussion by Mark Ptashne on his book, A Genetic Switch. Presumably this coincided with the release of the new edition: A Genetic Switch, Lecture Series.

Who’s a Nerd, Anyway?:

But the nerds she has interviewed, mostly white kids, punctiliously adhere to Standard English. They often favor Greco-Latinate words over Germanic ones (“it’s my observation” instead of “I think:), a preference that lends an air of scientific detachment. They’re aware they speak distinctively, and they use language as a badge of membership in their cliques. One nerd girl Bucholtz observed performed a typically nerdy feat when asked to discuss “blood” as a slang term; she replied: “B-L-O-O-D. The word is blood” evoking the format of a spelling bee. She went on, “That’s the stuff which is inside of your veins,” humorously using a literal definition. Nerds are not simply victims of the prevailing social codes about what’s appropriate and what’s cool; they actively shape their own identities and put those codes in question.

I think the researcher interviewed is a bit too obsessed with straight-jacketing nerds into a racial identity (white). I speak as a brown nerd, though I doubt I’m as socially antagonistic toward colloquial slang and conventional mores as the archetypical nerds. Rather, I think the key to nerditutde is the lower emphasis on being accepted and so assimilating the normative tardish value system (who cares if your friends make fun of you for reading? Keep at it!). Of course, many more socially aware intrinsic nerds become adept at mimicking the tardish comportment during high school, only to show their “true colors” in college when they continue to focus academically and go on to professional jobs. Any true nerdologist has to grapple with the reality that the majority of nerds might actually be “passing.”

Ancient and continuing Darwinian selection on insulin-like growth factor II in placental fishes:

…We found that IGF2 is subject to positive Darwinian selection coincident with the evolution of placentation in fishes, with particularly strong selection among lineages that have evolved placentation recently. Positive selection is also detected along ancient lineages of placental livebearing fishes, suggesting that selection on IGF2 function is ongoing in placental species. Our observations provide a rare example of natural selection acting in synchrony at the phenotypic and molecular level. These results also constitute the first direct evidence of parent-offspring conflict driving gene evolution.

I’ve discussed genomic imprinting before. Though not restricted to mammals, much of the work has been done on this taxon simply because gestation increases the window during which such conflicts could occur and the relatively high investment the mother makes into the development of the embryo/fetus. John Timmer at Ars Technica covered this paper in detail several weeks ago.

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Just a quick question for readers: does social networking software help out in your professional life? I’m a very tepid user of the various sites, I accept invites and so on, but it isn’t something I invest a lot of time on in building a large of number of friends/contacts or fleshing out my profile. I know that some research has shown that a professional contacts are often found through your second-tier relationships, that is, not close friends but good acquaintances and what not. People who you know, but whose contacts don’t overlap much with yours. So I suppose that’s the point of something like linkedin. But does it really work? I’ve receive much better contacts through the blog, email, e-lists and so on.

(note, I am not disputing that social networking software helps your personal or social life. I know many people who’ve gotten action through friendster or myspace, but no one who has made professional gains via linkedin)

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