Error detection and behavioural inhibition in young heavy drinkers.

BACKGROUND: Increases in inhibitory errors in heavy drinkers are established; less well-studied is whether heavy drinkers are aware of these errors in performance. Reductions in error detection and awareness limit the possibility for remedial action to be taken, and have implications for substance abusers seeking to control use: failure to monitor and/or adjust ongoing behaviour may be linked to using more or more often than intended, and failing to adjust behaviour after a slip. Here we report the first study of both inhibitory control and error awareness in young heavy drinkers, using behavioural and psychophysiological measures.

METHODS: Heavy drinkers (n=25) and light- or non-drinking controls (n=35) completed a difficult inhibitory task which required signaling the awareness of inhibitory errors on the subsequent trial, while brain electrical activity was recorded.

RESULTS: Heavy drinkers made more inhibitory errors than controls, but we observed no difference in error awareness, both via overt signaling and with equivalent amplitude of the error positivity (Pe), indexing conscious error detection. Similarly, controls and heavy drinkers showed no difference in amplitude or latency of the error-related negativity (ERN), indexing early pre-conscious error detection.

CONCLUSIONS: This research suggests no significant difference in detection of errors in heavy drinkers, even as they are more prone to make these errors, a result seen in dependent drinkers reported elsewhere. Future research with larger sample sizes, and a more difficult task producing sufficient errors, should determine whether heavy drinkers employ sufficient post-error remedial action.