Brain science is super interesting and important, of course. In fact, “the brain” is gaining on “the mind” as a topic of our brain-mind’s fixation (Google ngrams):
I take a tiny share of responsibility for this trend, as during one of my journalism careers I wrote a 1995 news article about “brain-based learning” for a newsletter sent to more than 100,000 K-12 educators.
On the plus side, in my old article I devoted considerable attention to the issue of brain plasticity, or how brains change in response to time and experience. That plasticity perspective was conspicuously absent from Michelle Trudeau’s NPR story this morning about the brains of extreme altruists. The story was based on a paywalled PNAS article which reported that a nonrandom group of 19 anonymous kidney donors had bigger right amygdalas, and heightened emotional response to pictures of faces, than a nonrandom group of 20 controls. The authors conclude that “these findings suggest extraordinary altruism [is] supported by neural mechanisms that underlie social and emotional responsiveness.”
Or, maybe the cumulative experiences of adults who turn out to be extraordinary altruists change their brains. (Or even, maybe the experience of giving a kidney itself affects people’s brains.) It appears that amygdala size changes within people over time, and that it is correlated with the size of people’s social networks. So, the causal sequencing here is something to consider.
What if, as they imply, something about the way people are born makes them more or less likely to be an extraordinary altruist versus a psychopath (a group this researcher previously studied). How much of the real-life variation in altruism might such a genetic or anatomical influence account for? If that proportion is low, then this is a fascinating evolutionary question with little social implication — worth studying, but not worth writing about with headlines like, “Good Deeds May Be Rooted In The Brain.”
The PNAS authors conclude:
It should be emphasized, however, that the mechanisms we have identified are unlikely to represent a complete explanation for altruistic kidney donation, given the extreme rarity of this phenomenon, and given the overlapping distributions we observed for the variables we measured. Acts of extraordinary altruism are likely to reflect a combination of the neurocognitive characteristics identified here, along with other individual- or community-level variables.
That seems like a safe bet, given this distribution of amygdala size across the two groups:
In short, we should consider the possibility, however slight, that altruism also has social causes. Disciplinary culture, I suppose, but I’ve never finished an article with a caution to readers that I may not have completely explained the phenomenon under study.