After assessing the 106 volunteers, she then gave them a computer-based task. They saw a picture of a human avatar in prison khakis, standing in a room, and facing either right or left. There were either two red dots on the wall in front of the avatar, or one dot in front of them and one dot behind them. Their job was to verify how many dots either they or the avatar could see.

Normally, people can accurately say how many dots the avatar sees, but they’re slower if there are dots behind the avatar. That’s because what they see (two dots) interferes with their ability to see through the avatar’s eyes (one dot). This is called egocentric interference. But they’re also slower to say how many dots they can see if that number differs from the avatar’s count. This shows how readily humans take other perspectives: Volunteers are automatically affected by the avatar’s perspective, even when it hurts their own performance. This is called altercentric interference.

Baskin-Sommers found that the psychopathic inmates showed the usual level of egocentric interference—that is, their own perspective was muscling in on the avatar’s. But they showed much less altercentric interference than the other inmates—the avatar’s perspective wasn’t messing with their own, as it would for most other people.