P300 from men with a family history of alcoholism under different incentive conditions.

OBJECTIVE

Males with a family history of alcoholism (Family History Positive [FHP]) have frequently been reported to show an attenuated amplitude of the P300 component of the EEG event-related potential (ERP). The purpose of the present study was to explore the influence of incentives on the amplitude of the P300 to Target stimuli in FHP and FHN (Family History Negative) men.

METHOD

The ERPs of 20 FHP and 20 FHN men were recorded in a visual discrimination task under two conditions: a no incentive (Neutral) and a reward/loss of reward (Incentive) conditions. ERPs following Target, Non-Target and Novel stimuli were examined.

RESULTS

The FHP subjects displayed the expected attenuation of P300 amplitude, regardless of the stimulus type (Target, Non-Target or Novel), compared to the FHN subjects. The FHN subjects showed the predicted effect of a significantly increased P300 amplitude following Target stimuli in the Incentive condition whereas the FHP subjects did not display significantly greater P300 amplitudes in response to the incentive.

CONCLUSIONS

These results may reflect a deficit in the motivational-cognitive system of FHP subjects. Analyses suggest that changes in P300 amplitude in response to the incentive can be predicted by subjects' scores on self-report measures of sensation seeking and behavioral undercontrol. However, such measures could not explain subjects' absolute P300 amplitude to Target stimuli.