amplitude of the oscillations that are phase-locked to a stimulus event, since averaging across trials tends to cancel out non-phase locked oscillatory activity. Accordingly, because the evoked power measure initially requires some consistency of phase across single trials, and then depends on the average magnitude of the phase-locked signal, evoked power deficits could be due to decreased phase-locking or to reduced single trial amplitude. Given that many previous studies have acknowledged the increase in phase variance (i.e., latency jitter) in measures of neural activity in patients with schizophrenia (Ford et al., 1994), it is surprising that very few studies (Krishnan et al., 2009) have assessed total power of the early auditory GBR in this population to separate magnitude from phase-locking abnormalities.
