Saturday, September 23, 2006

Adam Smith and the Neurology of Sympathy

In 1996, some Italian scientists studying the neural activity of macaque monkeys reported a remarkable discovery. They had been recording the neural activity in the premotor cortex of these monkeys whenever they engaged in a manual behavior such as picking up a raisin with their hands. Then one day, one of the scientists casually picked up a raisin with his own hand, and he was startled to notice that electrodes in the brain of the monkey were showing the same neural activity that appeared when the monkey picked up raisins. This scientific report claimed that there were "mirror neurons" in the brains of these monkeys--neurons that would fire when the monkey performed an action or when the monkey observed the same action performed by some other agent. Ever since then, research has confirmed the apparent existence of such neurons in various parts of the primate brain that suggest a neural basis for imitative learning and social understanding.

Research using brain imaging technology has shown that similar mechanisms exist in the human brain. Recent studies have uncovered a mirror system in the human brain that is more extensive and more complex than that found in other primates. Some areas of our brain become active both in response to our own actions and in response to sensory information about the same actions performed by others. This includes hearing actions or hearing language that resports such actions. If I hear someone eating candy, my brain will show activity in the same area that would be active if I were eating candy. Or if I hear a report of someone eating candy, the same brain area becomes active.

It has been suggested that these mirror systems might explain the capacity for empathy. And, indeed, it has been reported that people who score high on tests for empathy show a stronger activation of these mirror systems than people who scored low for empathy.

It seems possible, then, that our human capacity for "putting ourselves in someone else's shoes (or mind)" is literally just that. We rehearse mentally what another person is doing or experiencing by going through the same mental activity that we would have if we were ourselves doing or experiencing this.

This is what Adam Smith called "sympathy," or "fellow-feeling with any passion whatever," in the first chapter of The Theory of Moral Sentiments. In Darwinian Conservatism, I show how this underlies Smith's account of the moral sentiments, and how Charles Darwin adopted this in his biological acccount of morality. Our natural sociality, our natural capacity for imaginatively putting ourselves in the place of others, and our concern for judging how people appear to us as well as how we appear to others provide the natural basis for human morality and culture.

Now, if the research on "mirror neurons" is confirmed and deepened, this would sustain my argument about how morality and culture are rooted in human biological nature, because this would uncover the neural basis for such moral experience. Moreover, this could suggest an evolutionary pathway for human morality--the evolution of mirror systems in the primate brain could have brought about the emergence of human morality in the human brain.

Aristotle declared that human beings are by nature more political than the other political animals because by nature they have capacities for language and reason that allow them to organize communal life around shared conceptions of expediency and justice. Now we are seeing confirmation of Aristotle's biology of political animals by seeing how this political biology arises in the human brain's capacity to imaginatively project itself into the brains of others.


Anonymous said...

Is there any evidence that religious belief has a positive impact on the number of active (or present?) mirror neurons in an individual's brain?

Larry Arnhart said...

I don't know any such evidence.

What do you have in mind here?