DOSE-DEPENDENT EFFECTS OF ALCOHOL ON VISUAL-EVOKED POTENTIALS

The effects of various alcohol doses on components of the visual evoke d potential were investigated. Using a repeated measures, Latin square design, five alcohol dose conditions were administered to ten male su bjects: 0.00 (placebo); 0.28; 0.36; 0.54 and 0.72 g/kg total body weig ht. EEG responses to a reversing checker board stimulus were measured in a standard oddball paradigm. In the alcohol conditions, latencies o f the P1 and P2 components of the VEP were unaffected. However, reacti on time, and the latencies of N2 and P3 displayed significant dose rel ated increases with increasing blood alcohol levels. Further, RMS powe r of the P3 complex was reduced by higher alcohol doses, as was the N2 -P3 amplitude difference at central and parietal sites. It is conclude d that the latency and power of the endogenous components of the VEP a re altered by alcohol, without effects being seen in earlier component s.