Psychopaths tend to have a remarkably poor sense of smell, according to a new study by Australian scientists.
The studies found that such people have impaired functioning in the front part of the brain — the area largely responsible for functions such as planning, impulse control and acting in accordance with social norms.
Researchers at Sydney’s Macquarie University tested a theory that psychopathy — a severe personality disorder characterised by lack of empathy, antisocial behaviour and callousness — may be linked to impaired smelling ability.
Researchers Mehmet Mahmut and Richard Stevenson looked at whether a poor sense of smell was linked to higher levels of psychopathic tendencies, among 79 non-criminal adults living in the community, according to a Macquarie statement.
They assessed the participants’ olfactory ability as well as the sensitivity of their olfactory system.
They also measured subjects’ levels of psychopathy, looking at four measures: manipulation callousness erratic lifestyles and criminal tendencies.
They noted how much or how little they emphasised with other people’s feelings.
Researchers found that those individuals who scored highly on psychopathic traits were more likely to struggle to both identify smells and tell the difference between smells, even though they knew they were smelling something.
“Our findings provide support for the premise that deficits in the front part of the brain may be a characteristic of non-criminal psychopaths,” Mahmut and Stevenson said in a statement.