The results of the study highlight a significant lack of N400 attenuation for primed words in alcohol dependent subjects compared to controls, although both groups respond similarly in the unprimed condition. This lack of attenuation in N400 amplitude in alcoholics possibly reflects an inability to engage similar neuronal substrates as those associated with semantic relatedness in the control subjects. While these differences in the brain responses to semantic relatedness between groups are reflected in one aspect of behavior (reaction time difference between conditions) in this simple antonym pair task, it is likely that in more demanding tasks the brain responses would be associated with stronger behavioral effects. These altered mechanisms in alcoholics lead to less efficient information processing as, in contrast to controls, they are unable to benefit from available information (e.g. prime stimulus) to facilitate and optimize information processing. This is supported by the significantly less reaction time reduction between the unprimed and primed condition, observed in alcoholics when compared to controls. Similar findings of reduced N400 attenuation during priming have also been reported in young non-alcoholic offspring of
