Moderate acute alcohol intoxication increases visual motion repulsion.

Among the serious consequences of alcohol abuse is the reduced ability to process visual information. Diminished vision from excessive consumption of alcohol has been implicated in industrial, home, and automobile accidents. Alcohol is also generally recognized as an inhibitor in the brain by potentiating GABA-ergic transmission. In this study, we focused on visual motion processing and explored whether moderate alcohol intoxication induced changes in inhibitory mediated motion repulsion in a center-surround configuration. We conducted a double-blind, placebo-controlled, within-subjects study on the effect of alcohol on visual motion repulsion. Each subject underwent three experimental conditions (no alcohol, placebo and moderate alcohol) on separate days. The order of the placebo and moderate alcohol conditions was counterbalanced. The results showed that the effects of the surround context on the perception of the center motion direction were similar in both the sober (no alcohol) and placebo conditions. However, contextual modulations were significantly stronger during intoxication compared to both the sober and placebo conditions. These results demonstrate that moderate alcohol consumption is associated with altered neural function in visual cortical areas and that motion repulsion deficits might reflect the inhibitory effects of alcohol on the central nervous system.