Change in rapid eye movement (REM) sleep in response to exposure to all-night noise and transient noise.

Several experiments conducted by the authors revealed certain characteristic changes in stage rapid-eye-movement sleep in response to noise exposure. Continuous and all-night exposure to noise first decreased the percentage of rapid-eye-movement stage at Leg 45dBA. In contrast, the threshold of shifts from the rapid-eye-movement stage in response to intermittent noise was higher than thresholds noted for slow-wave sleep or stage-2 sleep. We concluded that these results indicated that a silent environment is required to maintain the duration of rapid-eye-movement sleep, even though rapid-eye-movement sleep is stable and is not influenced easily by noise.