Effects of Long Term Exposure to Tone Pulse Noise on Human Sleep

Abstract

Electrophysiological and self‐report data were obtained from 10 and 20 Ss, respectively, during 15 days of baseline, 30 days of 24‐hr per day exposure to a 660 msec, 3.5K Hz tone pulse with a 22 sec interstimulus interval (10 days each at 80, 85, and 90 dB), and during a 10‐day post‐exposure period. A self‐reported increase in difficulty falling asleep was not substantiated by objective sleep latency measures. Changes in total hours of sleep, number of awakenings, and percent time for sleep stages were of small magnitude and not consistently related to stimulus intensity. All 10 monitored Ss gave clear EEG and autonomic responses to the stimulus, with no evidence of response extinction over the 30‐day exposure period. There was no change in average all‐night heart rate. Total number of body movements during the night did not change. However, the movements that did occur, tended to be triggered by the stimulus, with most movements closely following the tone pulse. The youth and good health of the Ss, and the 24‐hr per day exposure, favoring rapid adaptation to the stimulus, are suggested to account for the lack of disruption of sleep.

Sleep, noise and health: Review

“…[26] Thirty subjects were monitored on a 24-h tone pulse for a 30-day exposure period and a 10-day post-exposure period. No significant change was found in mean heart rates at night, total body movements during the night, objective sleep latency, total hours of sleep, number of awakenings and percent time for sleep stages.…”

Effect of Sleep Disruption on Sleep, Performance, and Mood

“…Highly significant decreases in sensitivity to the auditory arousing stimulus were demonstrated. Because such threshold shifts might be due either to simple habituation (14,15) or to actual decreased sensitivity resulting from nonrestorative sleep, trials with novel frequency tones were interpolated for four sUbjects. Significant threshold increases (66% of the magnitude of threshold increase to the standard 1,000 Hz tone) were found to the novel stimuli as well as the standard tone.…”

“…Sharpless and Jasper (14) presented tones to sleeping cats and found that after approximately 30 presentations they could find no change in ongoing electroencephalogram (EEG) after tone presentation. Townsend et al (15) studied the effects of 80--90 dB tones each 22 s on sleep in young adult males and found essentially no change in sleep variables. However, this may have been because of rapid habituation and the fact that the initial nights of tone presentation were not analyzed separately.…”

Experiments on the time frame of temporally limited traffic curfews to prevent noise induced sleep disturbances

“…Other indicators of noise induced sleep disturbances such as event related awakenings were, due to the high traffic density regarded as not appropriate. The evaluation of arousals was also not considered as nocturnal noise scarcely increases the number of arousals but causes a temporal re-distribution of the arousals over night instead [30].…”