[Effect of abstinence on visual evoked potentials in alcoholics]

Visual evoked potentials (VEP) were studied in 61 alcohol-dependent subjects analysing the amplitude and latency of the first major positive wave (P100) and carrying out the determinations three times, in the 1st, 2nd and 3rd weeks of abstinence. The results were compared with similar ones obtained in healthy subjects without a history of alcohol abuse. In the acute stage of alcohol withdrawal a significant rise was observed in the amplitude of the cortical P100/N120 complex. With regression of the clinical symptoms of withdrawal syndrome the amplitude of visual potentials decreased and demonstrated partial normalization. The mean P100 latency was significantly longer in relation to the control group and was not changed during the withdrawal period. Amplitude increase was regarded as an evidence of hyperexcitability of the central nervous system, and latency prolongation as a result of the toxic effects of alcohol and nicotine on the optic nerve.