The Psychopath, the Altruist and the Rest of Us

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The neuroscientist Abigail Marsh at Georgetown University started out studying psychopaths–people like Scott Johnson. There is good scientific evidence that psychopaths are very different from other kinds of criminals. In fact, many psychopaths aren’t criminals at all. They can be intelligent and successful and are often exceptionally charming and charismatic.

Psychopaths have no trouble understanding how other people’s minds work; in fact, they are often very good at manipulating people. But from a very young age, they don’t seem to respond to the fear or distress of others.

Psychopaths also show distinctive patterns of brain activity. When most of us see another person express fear or distress, the amygdala–a part of our brain that is important for emotion–becomes particularly active. That activity is connected to our immediate, intuitive impulse to help. The brains of psychopaths don’t respond to someone else’s fear or distress in the same way, and their amygdalae are smaller overall.

But we know much less about extreme altruists like Paul Wagner. So in a study with colleagues, published in 2014 in Proceedings of the National Academy of Sciences, Dr. Marsh looked at the brain activity of people who had donated a kidney to a stranger. Like Mr. Wagner, most of these people said that they had made the decision immediately, intuitively, almost as soon as they found out that it was possible.

The extreme altruists showed exactly the opposite pattern from the psychopaths: The amygdalae of the altruists were larger than normal, and they activated more in response to a face showing fear. The altruists were also better than typical people at detecting when another person was afraid.

These brain studies suggest that there is a continuum in how we react to other people, with the psychopaths on one end of the spectrum and the saints at the other. {snip}

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