Psychopaths can 'switch on' empathy

An ability to empathise at will may partly explain the evil cunning of psychopaths, a study suggests.

Scientists had thought psychopaths, such as movie serial killer Hannibal Lecter, could not feel compassion because of their brain wiring.

But new research indicates that although naturally unaffected by other people's feelings, they can turn on the empathy when required.

"Psychopathy may not be so much the incapacity to empathise, but a reduced propensity to empathise paired with a preserved capacity to empathise when required to do so," study leader Dr Valeria Gazzola, from Groningen University Medical Centre in the Netherlands, said.

The ability to "switch on" empathy may contribute to the famous social cunning of psychopaths, the scientists said.

On a more positive note, the fact that psychopaths had empathy potential raised the possibility of harnessing it as a form of treatment.

The research, reported in the journal Brain, involved 18 convicted criminal psychopaths and a group of ordinary individuals who watched movie clips of one hand touching another in loving, painful, socially rejecting or neutral ways.

At certain points the volunteers were asked to "empathise with one of the actors in the movie".

Their responses, shown on brain scans, were compared with those seen when they engaged in similar hand interactions themselves.

The tests showed that when watching the film clips, psychopaths generally displayed a reduced level of brain responses linked to empathy.

But when explicitly asked to empathise, they were able to activate the circuits.

The study focused on the brain's "mirror system" which helps us feel other people's pain, almost literally.

The same brain regions that contribute to our own pain and distress are activated when we see another person suffering the same way.

In psychopaths, the mirror system does not seem to be a "default" mechanism but can be deliberately brought into play.