The mean N400 amplitudes at frontal, temporo-central and parietal regions in primed and unprimed conditions for control and alcohol-dependent groups are shown in table 2. The main effect of Group (F = 3.25; p = 0.074) showed only a trend towards differences in N400 amplitudes between groups. A significant main effect was observed for Condition (F = 34.07; p = 0.000) confirming a larger negative amplitude for unprimed compared to primed words. The results of the repeated measures ANOVA revealed a significant Group x Condition (F = 5.25; p = 0.023) interaction effect, indicating that alcohol dependent subjects had significantly larger negative amplitudes for the primed word condition when compared to control subjects. The Group × Region (F = 2.86; p = 0.06) interaction effect showed a trend towards significance because the highest differences between controls and alcoholics were centroparietal and the smallest were at the frontal regions.
