While the auditory ERP findings for CHR patients closely parallel those observed for olfactory stimuli in virtually the same cohort (Kayser et al., 2013), they contrast with previous reports of reduced P3a and/or P3b in CHR patients (Atkinson et al., 2012; Bramon et al., 2008; Frommann et al., 2008; van der Stelt et al., 2005; Özgürdal et al., 2008; van Tricht et al., 2010). Contrary to expectations, even the novelty vertex source (i.e., the most distinct positive component among this family of P3-like components) was not altered in CHR patients compared to healthy controls. Still, severity of negative symptoms was associated with reduced P3b, and severity of general symptoms was likewise related to the ensuing centroparietal source, that is, to ERP positivities that are typically not dissociated in conventional ERP studies (i.e., these are likely encapsulated under a broader concept of P3 or late positive complex). These findings are in line with prior evidence linking negative symptoms to P3 reductions in schizophrenia (e.g., Mathalon et al., 2000). Regarding the lack of overall P3 reductions in CHR patients, the reasons for
