A new study has suggested a poor sense of smell may be a marker for psychopathic traits.
Australian researchers studied 79 non-criminal adults and found those with psychopathic tendencies were more likely to struggle to both identify smells and tell the difference between them.
In a statement, the authors concluded: "Our findings provide support for the premise that deficits in the front part of the brain may be a characteristic of non-criminal psychopaths."
Psychopathy is a broad term that covers a severe personality disorder characterized by callousness, manipulation, sensation-seeking and antisocial behaviors, traits which may also be found in otherwise healthy and functional people.
Previous studies have shown that people with psychopathic traits 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.
In addition, a dysfunction in these areas in the front part of the brain is linked to an impaired sense of smell.
Researchers added: "Olfactory measures represent a potentially interesting marker for psychopathic traits, because performance expectancies are unclear in odour tests and may therefore be less susceptible to attempts to fake good or bad responses."
The research is published in online in Chemosensory Perception.