We previously demonstrated that B6 and D2 strains did not differ in overall EEG amplitudes (Ehlers and Somes, 2002). However, B6 mice showed significantly lower amplitude in the N1 and P3 ERP components in frontal and parietal cortices, when compared to the D2 strain. These findings suggested that B6 mice exhibited lower ‘responsivity’ to neurosensory stimuli and further confirmed that decreased P3 amplitude in this mouse model is associated with increased risk for enhanced alcohol consumption. The N1 component consists of the N1a component, a large negative component that peaks between 20 and 30 ms, and the N1b component, a broader negative component that peaks between 80 and 90 ms. The P3 component is a broad positive wave that peaks between 200 and 300 ms (Ehlers and Somes, 2002). Findings from the present study indicate that lower evoked alpha/beta band energy in the 0 to 50 ms time window, in response to standard and rare tones, may mediate the reduction in N1a amplitudes in B6 mice, compared to D2 mice. Consistent with their reduced N1a amplitudes (Ehlers and Somes, 2002),
