Event-related brain potentials to high incentive stimuli in abstinent alcoholics.

We have previously found that the P3 component of the event-related potential (ERP) is reduced in alcoholics in visual target-selection paradigms. P3 voltage depends on the "subjective significance" of the stimulus (e.g., task relevance, probability of occurrence, motivational factors). We were interested in assessing P3s in alcoholics to motivationally significant stimuli that did not differ with respect to other aspects of significance. Equiprobable, task-relevant visual stimuli with different acquired incentive values were presented to alcoholics under baseline and two incentive conditions. Alcoholics manifested similar lower P3 voltages without P3 latency delays to all stimuli, regardless of incentive values. Latency Corrected Averages indicated that these results were not due to latency jitter in the averages. These results suggest multiple system deficits in alcoholics, perhaps in involving frontal and/or medial temporal lobe, the brain sources implicated in the generation of P3. Our results perhaps reflect a deficit in motivational-cognitive systems in alcoholics, possibly affecting their ability to actively sustain information processing.