Is working memory intact in alcoholics? An ERP study.

Few investigators have applied the working memory theory to studies on abstinent chronic alcoholics, though it has been reported that the deficits in short-term memory appear to be specific to visuo-spatial and problem-solving tasks. In the present study, we recorded ERPs from 40 male control subjects and 78 alcoholics performing a modified delayed matching to sample task. To minimize the possible confound of retinotopic projections for the matching stimuli, in contrast to the non-matching stimuli, we employed a unique set of stimuli in our delayed matching to sample task. Our results indicate that an ERP component, occurring at approximately 250 ms post-stimulus, may be a reflection of the ERP mnemonic effect for working memory. This component distinguishes the two groups at the right occipitotemporal region, providing evidence of right hemisphere dysfunction in alcoholics. Thus, the current experiment may show electrophysiological evidence of working memory deficits in alcoholics.