AN ATTENTION deficit, rather than an inability to feel emotion, may be what makes psychopathic individuals seem fearless. It’s a finding that challenges the common characterisation of such people as cold-blooded predators.

“A lot of their problems may be a consequence of something that’s almost like a learning difficulty,” says Joseph Newman, a psychologist at the University of Wisconsin-Madison who investigated how prisoners with psychopathic personalities react when anticipating pain.

Previous experiments have suggested such people may not feel fear, while brain imaging studies have found abnormalities in the amygdala, a region that processes fear and other emotions. This has …