Published Online: 30 JAN 2010
Copyright © 2010 John Wiley & Sons, Inc. All rights reserved.
Corsini Encyclopedia of Psychology
How to Cite
Steiger, A. 2010. Sleep Cycle. Corsini Encyclopedia of Psychology. 1–2.
- Published Online: 30 JAN 2010
Sleep in mammals, including humans, and in birds has a cyclic structure. Polygraphic recordings (sleep electroencephalogram [EEG]) reveal the alternating occurrence of periods of non-rapid-eye-movement (nonREM) and rapid-eye-movement (REM) sleep. One sleep cycle consists of one nonREM and one REM period. Normal adult human subjects have three to five sleep cycles per night (see Figure 1).