Pathological liars have different brain structures

NEW YORK - Pathological liars may have structural abnormalities in their brains, a study suggests.

Scientists at the University of Southern California found that people who habitually lied or cheated had less grey matter and more white matter in their prefrontal cortex than normal individuals.

They report their findings in the British Journal of Psychiatry.

Past studies have found that the prefrontal cortex shows heightened activity when normal people lie, and it is believed to be involved in both learning moral behaviour and feeling remorse.

Because grey matter consists of brain cells, while white matter forms the "wiring" or connections between these cells, pathological liars may have more capacity to lie and fewer moral restraints.

"They've got the equipment to lie, and they don't have the disinhibition that the rest of us have in telling the big whoppers," Dr Adrian Raine said.

The researchers used a series of psychological tests and interviews in a group of volunteers to identify 12 pathological liars, 16 people with antisocial personality disorder but no history of lying, and 21 normal people.

They then examined the brains of all study participants using magnetic resonance imaging.

Liars had 26 per cent more white matter in their prefrontal cortex than people with antisocial personality disorder, and 22 per cent more than normal people. But they had 14 per cent less grey matter than normal individuals.

- REUTERS