Studies over the last few decades have found that the amplitudes of P3s to task-relevant target stimuli (P3b) are significantly lower in abstinent alcoholics than in nonalcoholics (for reviews, see Porjesz and Begleiter 1996, 1998). This deficit in alcoholics occurs with both auditory and visual tasks but is seen more consistently with visual tasks. More recent studies have indicated that low P3 amplitudes are present not only in male alcoholics but also in female alcoholics, though not to the same extent as in males. Figure 2A illustrates reduced P3 amplitudes in alcoholics, compared with control subjects, in response to target stimuli in a visual paradigm.
