A consistent EEG finding during rest in SZ is augmented low-frequency power at delta and theta (Gattaz et al. 1992; Clementz et al. 1994; Sponheim et al. 1994, 2000). This anomaly has been observed in medication-free patients (Miyauchi et al. 1996), across medication status (Gattaz et al. 1992) and regardless of duration of illness (Sponheim et al. 1994). EEG studies of patients and their relatives have reported increased low-frequency power in patients only (Clementz et al. 1994; Venables et al. 2009), indicating increased low frequency power could be associated with psychotic symptoms rather than familial risk.
