Modification of the startle reflex in a community sample: do one or two dimensions of psychopathy underlie emotional processing?

Recent research on psychopathy has begun to explore two dimensions that possibly underlie psychopathy–one related more to emotional and interpersonal traits, and another related more to antisocial behaviors. A community sample of adults was assessed for psychopathy using Hare's (1991) Psychopathy Checklist-Revised (PCL-R). Eyeblinks elicited by startle probes were recorded while participants viewed pictures of emotionally-laden stimuli. Consistent with previous research, participants scoring high on PCL-R Factor 2 (“antisocial”) showed no affective modification of startle if they also scored high on PCL-R Factor 1 (“emotional detachment”). When the factor scores were analyzed together as continuous variables in a regression analysis, however, affective modification of startle was negatively related to Factor 1 but positively related to Factor 2. The results thus provide further support for a two-factor model of psychopathy.