The crossmodal facilitation effect is disrupted in alcoholism: a study with emotional stimuli.

AIMS Chronic alcoholism is classically associated with major deficits in the visual and auditory processing of emotions. However, the crossmodal (auditory-visual) processing of emotional stimuli, which occurs most frequently in everyday life, has not yet been explored. The aim of this study was to explore crossmodal processing in alcoholism, and specifically the auditory-visual facilitation effect. METHODS Twenty patients suffering from alcoholism, and 20 matched healthy controls had to detect the emotion (anger or happiness) displayed by auditory, visual or auditory-visual stimuli. The stimuli were designed to elicit a facilitation effect (namely, faster reaction times (RTs) for crossmodal condition than for unimodal ones). RTs and performance were recorded. RESULTS While the control subjects elicited a significant facilitation effect, alcoholic individuals did not present this effect, as no significant differences between RTs according to the modality were shown. This lack of facilitation effect is the marker of an impaired auditory-visual processing. CONCLUSIONS Crossmodal processing of complex social stimuli (such as faces and voices) is crucial for interpersonal relations. This first evidence for a crossmodal deficit in alcoholism contribute in explaining the contrast observed between experimental results describing, up to now, mild impairments in emotional facial expression (EFE) recognition in alcoholic subjects (e.g. Oscar-Berman et al.,1990), and the many clinical observations suggesting massive problems.