Contrary to popular belief, a lack of behavioural inhibitory control may not be associated with aggression

Background: Neuropsychological impairment in 'prefrontal' abilities, including inhibitory control, is theoretically linked to aggression. A potential clinical application involves the use of neuropsychological measures to predict violence within secure settings. This preliminary study investigates the association between behavioural inhibition (here the suppression or cessation of an inappropriate response) and aggression.

Method: Ten violent male hospitalized offenders were compared with 10 healthy age- and IQ-matched men on two neuropsychological measures of behavioural inhibition. Incidents of aggression were recorded for the next five weeks for the offender group.

Results: Offenders displayed a general trend for reduced inhibitory control compared with the healthy men. Contrary to expectation, however, within the offender group, problems with behavioural inhibition were not associated with aggressive incidents in the short term.

Conclusions: This preliminary study is limited by a small sample size and short period of aggression measurement but it illustrates the need to be cautious about making inferences regarding possible mediators of aggression from one form to another and without taking account of context.