Atkinson et al. (2012) also reported that an early P3 subcomponent with a frontocentral distribution, termed P3a, was reduced in CHR individuals, but this deficit was unrelated to MMN reductions. Reduced amplitudes of duration MMN and P3a have also been found in 17 first-episode patients, underscoring the potential phenotype value of both EEG measures (Hermens et al., 2010). Of interest, Salisbury et al. (2002) found reduced MMN to deviations in pitch for chronic schizophrenia (n = 16) but not for 21 first-episode patients, suggesting that MMN to deviations of tone duration reflect different aspects of neurophysiological processing. Notably, most of this ERP research in schizophrenia and CHR patients has relied on standard two-tone paradigms, but P3a is particularly evident to perceptually novel distractors embedded in a series of frequent nontarget and infrequent target stimuli, and has therefore been termed novelty P3 (Polich, 2007). In such a three-stimulus oddball task (Friedman et al., 1993), novelty P3 and P3b can be readily distinguished by their topographic differences (mid-frontocentral vs. mid-parietal maximum) and condition dependencies. Although a novelty oddball paradigm has previously been
