Developmental trends of auditory novelty oddball P3 while accounting for N2 in 7- to 25-year-olds.

Many previous studies examining developmental trends in P3 amplitude or latency have used a two-stimulus (standard and target) oddball paradigm. Fewer studies exist using the novelty oddball paradigm, a three-tone (standard, target, and novel) paradigm. In this study with 204 typically developing participants aged 7-25 years, the influence of participant traits-age and sex-on the developmental trends of P3 peak-to-peak amplitude and latency were examined. Additionally, interactions between the three tones of the novelty oddball paradigm and scalp sites on P3 amplitude and latency were evaluated. While previous studies using baseline-to-peak measures have shown smaller P3 amplitude in children compared with adults, this study, using peak-to-peak measures (P3 minus N2 amplitude), found the opposite effect with children having larger P3 amplitudes than adults. This finding is explained by further analyses of N2, representing discrimination. N2 baseline-to-peak amplitude significantly predicted P3 baseline-to-peak amplitude; a mediation effect such that as N2 becomes less negative, P3 becomes larger. Regression analyses revealed that developmental trends of the P3 amplitude were primarily linear, but trends in P3 latency were mostly non-linear. Sex differences were observed, although limited to latency measures. Results from ancovas found significant interactions between the three tones and between frontal (Fz) and parietal (Pz) sites, with larger P3 amplitude during target and novel tones at Pz than Fz, and larger amplitudes during frequent tones at Fz than Pz. These findings highlight the importance of considering more than P3 amplitude in understanding developmental trends in cognitive processing during oddball paradigms.