Effects of Time Zone Changes on Sleep.
Endo-S; Yamamoto-T; Saski-M
NIOSH 1981 Jul:517-547
Effects of time zone changes on biological rhythm were studied. Electroencephalograms, electrooculograms, and electrocardiograms were recorded simultaneously on six male civilian aviation members after their nonstop flight from Tokyo (TYO) to San Francisco (SFO). Slow wave sleep (SWS) was increased and rapid eye movement (REM) sleep was depressed during the 11 to 12 hour long sleep. Intrasleep cycles were disturbed and pulse rate was high in the first half of sleep. REM sleep latency decreased significantly on returning to TYO. Percentage of REM sleep decreased on arrival at SFO, while percentage of SWS increased. After the return to TYO, REM sleep was less than in baseline nights. After a flight from TYO to Sydney (SDY), no change was observed in distribution of REM sleep periods on the first night, but on the second night REM sleep increased. Percentage of SWS increased the first night in SDY and decreased the second night. Proportion of REM percentage in the first and last part of sleep did not change, and percentage of SWS increased in the first half of sleep. A subject staying in SFO for 10 days after arrival from TYO had REM sleep baseline pattern recovery after 8 days. The same delay period was observed on return to TYO. Synchronization in sleep returned to baseline within the same periods. Pulse rate remained desynchronized for 10 days in SFO and synchronized with baseline 5 days after returning to TYO. In flight from TYO to London (LDN), there was an increase in REM sleep periods the first night, predominantly in the first part of sleep. Latencies in sleep and REM sleep were reduced on nights in LDN and gradually increased to baseline level. Mean pulse rate was elevated by the third night and restored to baseline the fourth night in LDN. The authors state that the data support the assumption that desynchronization syndrome including sleep disturbances may be attributable to time zone changes.
Sleep-deprivation; Sleep-disorders; Pilots; Circadian-rhythms; Airport-personnel; Aircraft; Health-protection; Biological-factors; Psychophysiology;
The Twenty-Four Hour Workday: Proceedings of a Symposium on Variations in Work-Sleep Schedules, Division of Biomedical and Behavioral Science, NIOSH, U.S. Department of Health and Human Services, Cincinnati, Ohio, DHHS (NIOSH) Publication No. 81-127