Abigail (Abby) Marsh

And I discovered just how much altruism plays a part when I started recruiting people who are altruistic.

The germ of this research was research I'd conducted previously in people who were at the opposite end of what I call the caring continuum.

So people vary quite a bit in their capacity to care about other people's welfare.

And at the low end of this continuum are people who are psychopathic.

So people who have callous personalities and engage in frequent antisocial behavior.

And what we've known from over a decade of research with people who are psychopathic is that they tend to be insensitive to other people's distress.

They have trouble recognizing it.

So if they see the face of somebody who's afraid, they might not even know what the expression is called.

A friend of mine, Essie Beding, in the United Kingdom was testing a psychopathic person in a jail once about their ability to recognize emotional facial expressions.

And this man failed to recognize every single fearful facial expression that she showed him.

And he knew he was doing badly.

And that is a pretty bad performance, even for somebody who's psychopathic.

Because when he got to the very last fearful expression, he said, you know, I don't know what that expression is called, but I know that's what people look like right before you stab them.

And this reveals a real sort of emotional blindness to other people's distress, which may help us understand why people who are psychopathic are so callous in response to other people's distress.

They don't even really know how to interpret it very well.

And the origin of that is partly deficits in a brain structure called the amygdala.

And the amygdala is a complicated brain structure.

It does a lot of different things.

But it's not essential for doing that many things.

One of the things that seems to be really important for doing is representing fear in other people.