An objective measure of REM activity

Abstract

Recent emphasis on REM sleep abnormalities has begun to yield significant differences between “normals” and patients with affective syndromes or schizophrenia. In our efforts to objectively quantitate aspects of REM sleep during all-night studies in psychiatric patients, we have developed the “REM analyzer” for automatic on-line measurement. As a practical application of the REM analyzer, 20 psychiatric patients (12 inpatients and 8 outpatients) were studied. Both cross-sectional and longitudinal-sleep studies were obtained; predrug and drug periods were also compared. From the REM analyzer, the number of rapid eye movements during each REM period (Cn) and the sum of their integrals during each REM period (In) were recorded. The ratio I/C was named “REM weight” (the “average rapid-eye-movement area“). The objective measures of REM sleep which highly correlate with a number of visual methods of defining REM sleep and with diagnostic and therapeutic implications in affective and schizophrenic disorders are discussed in this paper. The method appears particularly suitable for the differentiation of tonic and phasic components of REM sleep and, thus, for the investigation of REM suppression-compensation models. © 1974, Psychonomic Society, Inc.. All rights reserved.