A neuropsychological study of older adult first-time sex offenders.

ABSTRACT

BACKGROUND/AIMS: The issue of whether sex offenders have cognitive deficits remains controversial. The objective of this study was to compare the neuropsychological function of older adult first time sex-offenders (FTSO), who had not previously been charged with a sexual offence prior to the age of 50, to historical long-term sex offenders (HSO) and non-sex offenders (NSO). The hypotheses were (a) that FTSO would demonstrate greater deficits in executive function, decision-making, and memory compared to non-sex offenders; and (b) the HSOs would present similar neuropsychological deficits to non-sex offenders. METHOD: A battery of neuropsychological measures was administered to 100 participants comprising 32 FTSOs, 36 HSOs, and 32 NSOs. RESULTS: Both FTSOs and HSOs showed significant impairment on tests of executive function (including verbal fluency, trail-making, and the Hayling test of response inhibition) as well as on tests of verbal and verbal memory compared to NSOs; however, there was no difference between the two sex offender groups. CONCLUSIONS: Older adult sex offenders, overall, demonstrated poorer neuropsychological performance than older adult non-sex offenders did, although there was no difference between older first-time and historical offenders. Cognitive deficits may increase the risk of sexual offending due to impaired capacity in self-regulation, planning, judgment, and inhibition. A proportion of older adult sex offenders may be harboring acquired frontal lobe pathology.