3.2 P2 Adaptation
Similarly, the average peak amplitudes of the P2 were first extracted across the first ten positions to construct adaptation curves. As depicted in Figure 2b, there was an increasing trend in P2 amplitude with the first ten stimuli. Paired-sample t-tests revealed no significant differences between individual tone pairs after adjusting for Holm-Bonferroni corrections (P > .006). However, a significant linear trend was observed both from the 1st to 10th tones (F1,36 = 26.90, P < .001, MSE = 7.43, ηp2 = 0.43) and from the 2nd to 10th tones (F1, 36 = 33.28, P < .001, MSE = 7.64, ηp2 = 0.48). These findings indicate a continuous amplitude increase in the P2 time window, extending beyond the initial two tones (Figure 2b).