Sleep disturbance caused by shooting sounds

In the present study relations between the sound level of shooting sounds and the probability of behaviorally confirmed noise‐induced awakening reactions were determined. The sounds were presented by means of loudspeakers in the bedrooms of 30 volunteers. The shooting sounds had been produced by a small and a medium‐large firearm, and the stimuli consisted of individual bangs or volleys of ten isolated or partly overlapping impulses. Aircraft sound was included as a reference source. The sounds were presented during a 6‐h period that started 75 min after the beginning of the sleeping period. The time period between the various stimuli varied between 12 and 18 min, with a mean of 15 min. To cope with at least a relevant portion of habituation effects, each subject participated in 18 nights to be completed within 4 weeks. Preliminary results are presented both for the awakening reactions described above, and for various other dependent variables collected with the help of an actimeter or determined by means of subjective rating scales. [Work supported by the Dutch Ministry of Defense.]