Another aim of this study was to assess patients on the phase synchrony of the GBR using PLF. Consistent with other studies of older chronic patients (Mulert et al., 2011; Roach and Mathalon, 2008; Roach, this issue; Slewa-Younan et al., 2004; Spencer et al., 2009), the current study showed significantly diminished PLF of the GBR in young schizophrenia patients. Interestingly, marginal deficits in GBR phase consistency were present in CHR patients, where the degree of reduction in gamma synchrony was intermediate to healthy controls and young schizophrenia patients. Our findings of an intermediate effect in the at-risk group relative to healthy controls and schizophrenia patients are similar to findings in the literature (e.g., Brockhaus-Dumke et al., 2005; Brockhaus-Dumke et al., 2008b; Perez et al., 2011a; van der Stelt et al., 2005) reporting that CHR groups demonstrate intermediate effects that are not statistically distinguishable from either comparison group (i.e., the HC or SZ groups). In light of this, the nearly significant reduction of gamma PLF in the CHR patients suggests that deficient early auditory gamma-band phase synchrony predates the onset of schizophrenia.
