Research has demonstrated inconsistent results regarding the relationship between impulsivity and the interpersonal and affective facets of psychopathy. Therefore, the purpose of this work was to clarify and reconcile the variable empirical findings. Generally speaking, the relationship between psychopathic traits and impulsivity was expected to differ based on the psychopathy factor and type of impulsivity under investigation.
Studies 1 and 2 examined psychopathy and impulsivity in on-line and student samples, utilizing the Self-Report Psychopathy Scale and several self-report measures of impulsivity. Study 2 included laboratory-assessed behavioural impulsivity measures. Results indicated that across studies erratic lifestyle was uniquely, positively associated with all self-reported impulsivity measures, but surprisingly unrelated to laboratory-assessed behavioural impulsivity. Interpersonal manipulation was uniquely, negatively associated with lack of premeditation and non-planning, and callous affect was uniquely, negatively associated with urgency across studies.
Studies 3 and 4 examined the psychopathy-impulsivity relationship in youth and on-line samples. Psychopathy was examined using the Antisocial Process Screening Device (youth) and the Self-Report Psychopathy Scale (adults). Impulsivity was approximated via preselected facets of the HEXACO-PI-R and the UPPS Impulsive behavior scale (Study 4 only). Results indicated that the impulsivity (youth) and erratic lifestyle (adults) subscales were uniquely associated with heightened impulsivity. Callous-unemotional traits in youth were also associated with higher levels of impulsivity. In adults, interpersonal manipulation and callous affect were largely unrelated to impulsivity at the multivariate level (with few exceptions).
Findings demonstrated that the behavioural characteristics of psychopathy contributed to a pervasive tendency towards a variety of impulsive behaviours. This relationship was consistent across the youth, adult, on-line, and student samples. Among adults, the emotional and interpersonal psychopathy traits may be unrelated to impulsivity. Interpersonal manipulation traits may result in a slightly greater tendency to demonstrate premeditated, planned behaviour, whereas callous affect may reflect slightly lower urgency. However, callous-unemotional traits in youth do appear to be related to heightened impulsivity. Findings provide a better understanding of the psychopathy-impulsivity relationship. This is the first set of studies to utilize the HEXACO model to approximate pre-established impulsivity domains. Findings also address the issue of suppression when examining multifaceted constructs, particularly psychopathic traits
