Testing the REM sleep phasic event intrusion hypothesis of schizophrenia

Middle ear muscle activity (MEMA) and periorbital integrated potentials (PIPs) were recorded during rapid eye movement (REM) periods and during the 10 minutes preceding and following REM periods in normals, schizophrenic patients, and patients with schizoaffective and major depressive disorder. Contrary to the phasic event intrusion hypothesis, we observed no leakage or redistribution of MEMA or PIPs from REM into the surrounding stages of non-REM in the schizophrenic patients. Within REM, MEMA rate distinguished patients with schizophrenia from patients with schizoaffective disorder. Schizophrenic patients had higher than normal MEMA rates, whereas the schizoaffective patients had lower than normal MEMA rates.