Psychopathic traits predict startle habituation but not modulation in an emotional faces task

The psychophysiological correlates of psychopathic traits in normal-range samples have been a topic of recent interest in studies of the biological basis of personality. It is well established that psychopaths demonstrate abnormal patterns of startle potentiation while viewing emotionally evocative pictures, but this effect has not been demonstrated using pictures of facial affect. Recent research has also indicated that an individual's rate of habituation to an acoustic startle probe may be a reliable correlate of certain personality traits; however, this has not been investigated with psychopathic personality traits. We measured psychopathic personality traits in non-incarcerated young adults and investigated startle physiology while participants viewed pictures of facial affect. We found that psychopathic personality traits had no effect on startle modulation by emotional face category; however, the antisocial dimension of psychopathic traits was strongly associated with slower rates of habituation to the startle probe. This finding highlights the relevance of psychopathy's underlying constructs of emotional functionality and behavioral inhibition, and suggests a relationship between basic sensory habituation and the broader concept of inhibition as it relates to personality and behavior.