Abstract
This paper examines napping effects on arousal level in a night duty taken by hospital nurses. Nine healthy unmarried hospital nurses had participated in this experimental field study. They were subjected to both “nap condition” and “no-nap condition”. They took nap from 2:30 to 4:00 (a formal nap period in the hospital) under nap condition. Under no-nap condition, they chatted with an experimenter in that period. Measurements during awakening had carried out 90min. intervel from 23:30 to 10:00. The measures are CFF (Critical Flicker Fusion Frequency), 4 SRT (4 Selective Reaction Time), SFF (Subjective Fatigue Feelings) and KSS (Kwansei-Gakuin Sleepiness Scale: it was modified Stanford Sleepiness Scale for Japanese). During sleep periods, polygram was measured by ambulatory monitoring system. The results are that they slept for 59.6min. during napping period. Its sleep structure occupaied stage 2 (31.8min.), and little consisted of SWS and REMS. However, under nap and no-nap condition, there was signiicant difference between in CFF, 10% faster 4 SRT and SFF (factor of sleepiness and dullness" and “difficulty in concentration”) after 5:30. It was suggested that a small amount of SWS and REMS in a sleep structure of a nocturnal nap has an effect of improving arousal level during a night duty.
