To test the hypothesis that slow wave sleep in schizophrenia is inversely correlated with ventricular system volume, polysomnography and computed tomographic (CT) brain imaging were carried out in 14 psychiatric patients who met Research Diagnostic Criteria for schizophrenia (n = 11) or schizoaffective disorder (n = 3). Three measures of ventricular system volume were analyzed: (1) raw ventricular volume expressed in cm3; (2) ventricle-to-brain ratio; and (3) ventricular volume corrected for normal variation in age and head size expressed as a standardized (z) score. All three quantifications of ventricular volume were significantly and inversely correlated with visually scored measures of stage 3 and stage 4 sleep. This finding suggests that the etiology of slow wave sleep deficits in schizophrenia is related either directly or indirectly to underlying brain dysmorphology.
Bibliographical noteFunding Information:
This investigation was supported in part by the Medical Research Service of the Department of Veterans Affairs and by a grant from the National Institute of Mental Health (MH-30854). The authors thank the patients and staff of the DVA/ Stanford Mental Health Clinical Research Center for their invaluable help in this investigation and gratefully acknowledge the statistical and technical assistance of Daniel H. Mathalon, Kenneth Chow, and Brian Matsumoto.
- Schizoaffective disorder
- Ventricle-brain ratio
- Ventricular system