Event-related potential characteristics in children of alcoholics from high density families

Sons and daughters (ages 8-14) of male alcoholics without psychiatric problems were compared with sons and daughters of controls employing two auditory paradigms to elicit event-related potentials (ERPs). All of the children of alcoholics were from high density families (each father had an average of 3.7 first and second-degree relatives meeting criteria for alcoholism). Subjects were presented with high- and low-pitched tones with global probabilities of 25% and 75% of total trials, respectively. Subjects were instructed to count silently the number of "high" tones (rare targets) but not the number of "low" tones (non-targets) and report the number heard. In a second auditory paradigm (Choice Reaction task), subjects were asked to perform a different motor response to each high or low tone. The amplitude of the P300 component was influenced significantly by event probability (decreased amplitudes were associated with increased event probability). A greater rate of decrease in P300 amplitude occurred among the high risk children as event probability increased. In addition, greater negativity beginning at approximately N250 was observed for both tasks at the frontal electrode for the high risk children as compared to controls. This enhanced frontal negativity is interpreted in terms of a maturational lag hypothesis.