Detection of REM, 1 Sleep Stage and Eye Movement from Beat-to-Beat Heart Rate.

Abstract : Interest in using sleep stage patterns to determine the amount and quality of a pilot or astronaut's sleep has led to a series of Air Force sponsored studied. The ultimate goal of these studies is to be able to determine sleep stage from beat-by-beat heart rate data along (not using the EEG). Work performed at the University of Texas by Welch, et al, and Aldredge et al, has indicated that stage REM (rapid eye movement sleep) is refractory to detection by techniques which perform satisfactorily on the other sleep stages. In addition, the Welch algorithm performs more effectively when the times of occurrence of stage REM (or combined stages REM and 1) are already known. The purpose of this phase of study is to test the hypothesis that the occurrence of rapid eye movements can be detected by concurrent transient oscillations in the heart rate. A knowledge of REM occurrences would then greatly simplify recognition of the REM sleep stage. Alternatively, direct recognition of stage REM, 1 (stage REM + stage 1) sleep may be possible by spectral analysis of heart rate. Both possibilities are investigated. (Modified author abstract)