title: Covert effects of alcohol revealed by event-related potentials.
abstract: Contradictory evidence as to the effects of alcohol on early information processing stages has been obtained from behavioral and psychophysiological investigations. In the present study, choice reaction times, error rates, and event-related potentials (ERPs) were recorded in a task in which variations in stimulus discriminability and of the (task irrelevant) correspondence between stimulus location and response location were orthogonally combined. Both discriminability and stimulus-response correspondence affected reaction time and electrophysiological chronometric measures as expected. However, no behavioral effects of alcohol were observed, possibly because of strategic adjustments. Psychophysiological chronometric measures indicated that alcohol leaves the initial flow of perceptual evidence to motor stages unimpaired, whereas it appears to increase the duration of stimulus evaluation. Interestingly, a number of alcohol effects appeared in the ERP amplitudes. Decrements in early ERP components indicate alcohol-induced impairments of involuntary visual attention and/or the automatic stimulus location-dependent activation of response channels. In contrast, a strong enhancement of a late slow-wave component under alcohol may reflect the investment of processing resources in order to maintain normal performance levels.
authors.affiliation: Fachgruppe Psychologie, Universität Konstanz, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Sommer
authors.forename: H
authors.initials: H
authors.lastname: Leuthold
authors.forename: M
authors.initials: M
authors.lastname: Hermanutz
mesh_terms: D000328:Adult; D000428:Alcohol Drinking / Q000503:physiopathology*; D001143:Arousal / Q000187:drug effects* / Q000502:physiology; D001288:Attention / Q000187:drug effects / Q000502:physiology; D002540:Cerebral Cortex / Q000187:drug effects / Q000502:physiology; D004569:Electroencephalography / Q000187:drug effects*; D000431:Ethanol / Q000493:pharmacokinetics; D005074:Evoked Potentials, Visual / Q000187:drug effects / Q000502:physiology; D006801:Humans; D008297:Male; D010364:Pattern Recognition, Visual / Q000187:drug effects / Q000502:physiology; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology
chemical_list: D000431:Ethanol