Dehumanization on the Brain

by F.

BPS Research Digest summarizes some recent research by Lasana Harris and Susan Fiske. They

scanned the brains of ten Princeton university students while they viewed pictures of people from different social groups.

As predicted, pictures of sporting heroes, the elderly and businessmen all triggered activity in a region of the brain – the medial prefrontal cortex – known to be associated with thinking about other people or oneself.

By contrast, pictures of the homeless or of drug addicts failed to trigger activity in this area, and instead prompted activity in the areas of the brain related to disgust. “Members of some social groups seem to be dehumanised, at least as indicated by the absence of the typical neural signature for social cognition”, the researchers said.

A second study with 12 students confirmed that, like pictures of the homeless or of drug addicts, images of objects also failed to trigger activity in the medial prefrontal cortex – except for the sight of money, which participants said caused them to think about wealthy people.

So homeless man = coffee table. Not a huge amount of illumination from the glowing fMRI machine, but interesting nonetheless.