Adapting to phase shifts, I. An experimental model for jet lag and shift work

An experimental model was developed to measure various behavioral and physiological parameters in a laboratory paradigm mimicking phase shifts that could occur in time-zone transitions and shift work rotas. Volunteers were exposed to 9-h pulses of bright light (1,200 lx) as follows: day (D)1: 1800-0300 h, D2: 2100-0600 h, and D3, 4, 5: 2400-0900 h, each period followed by 8 h darkness. Immediately following the last treatment, subjects resumed their baseline sleep/wake schedule in a normal environment, thus experiencing a rapid 9-h advance phase shift of local time cues. During the gradual delay shift, a progressive delay shift in the rhythms of urinary 6-sulphatoxymelatonin (aMT6s), temperature and alertness was evident (maximum shift: 9.13 +/- 0.83 h, 9.09 +/- 1.06, and 10.62 +/- 0.96 h, mean +/- SD, respectively). There were no important detrimental effects on behavioral variables. After the rapid 9-h phase advance, sleep patterns, temperature amplitude, aMT6s acrophase, alertness, and performance took at least 5 days to reestablish normal baseline patterns. This model provides an effective and inexpensive model to study adaptation strategies in real life.

[1]  S. Folkard,et al.  Bright light phase shifts the human melatonin rhythm during the Antarctic winter , 1987, Neuroscience Letters.

[2]  H. Andersen,et al.  Adjustment of sleep and the circadian temperature rhythm after flights across nine time zones. , 1989, Aviation, space, and environmental medicine.

[3]  J. Waterhouse,et al.  Adaptation to abrupt time shifts of the oscillator(s) controlling human circadian rhythms. , 1978, The Journal of physiology.

[4]  W. Colquhoun.  Phase shift in temperature rhythm ffter transmeridian flight, as related to pre-flight phase angle , 1979, International archives of occupational and environmental health.

[5]  S. Daan,et al.  Scheduled exposure to daylight: a potential strategy to reduce "jet lag" following transmeridian flight. , 1984, Psychopharmacology bulletin.

[6]  H. M. Wegmann,et al.  Sleep, sleepiness, and circadian rhythmicity in aircrews operating on transatlantic routes. , 1986, Aviation, space, and environmental medicine.

[7]  C. Eastman.  Squashing versus Nudging Circadian Rhythms with Artificial Bright Light: Solutions for Shift Work? , 2015, Perspectives in biology and medicine.

[8]  S. Gerathewohl,et al.  Time-zone effects. , 1969, Science.

[9]  W P Colquhoun,et al.  Experimental studies of shift-work. 3. Stabilized 12-hour shift system. , 1968, Ergonomics.

[10]  C. Eastman,et al.  High-intensity light for circadian adaptation to a 12-h shift of the sleep schedule. , 1992, The American journal of physiology.

[11]  D A Newsome,et al.  Light suppresses melatonin secretion in humans. , 1980, Science.

[12]  C. Eastman.  Bright Light in Work-Sleep Schedules for Shift Workers: Application of Circadian Rhythm Principles , 1987 .

[13]  S. Folkard,et al.  Some effects of jet-lag and their alleviation by melatonin , 1987 .

[14]  J. Arendt,et al.  Radioimmunoassay for 6-Sulphatoxymelatonin in Urine Using an Iodinated Tracer , 1988, Annals of clinical biochemistry.

[15]  Karl E. Klein,et al.  Significance of Circadian Rhythms in Aerospace Operations , 1980 .

[16]  R. Wever,et al.  Light Effects on Human Circadian Rhythms: A Review of Recent Andechs Experiments , 1989, Journal of biological rhythms.

[17]  M. Byrne,et al.  Demonstration of rapid light-induced advances and delays of the human circadian clock using hormonal phase markers. , 1994, The American journal of physiology.

[18]  E. van Cauter,et al.  Effects of "jet lag" on hormonal patterns. II. Adaptation of melatonin circadian periodicity. , 1981, Journal of Clinical Endocrinology and Metabolism.

[19]  Anna Wirz-Justice,et al.  A human phase-response curve to light , 1991, Neuroscience Letters.

[20]  D C Holley,et al.  A review of human physiological and performance changes associated with desynchronosis of biological rhythms. , 1984, Aviation Space and Environmental Medicine.

[21]  R. Kronauer,et al.  Bright light induction of strong (type 0) resetting of the human circadian pacemaker. , 1989, Science.

[22]  R. Wever,et al.  Re-entrainment of circadian rhythms after phase-shifts of the Zeitgeber. , 1975, Chronobiologia.

[23]  D. Dijk,et al.  Effect of a single 3-hour exposure to bright light on core body temperature and sleep in humans , 1991, Neuroscience Letters.

[24]  T H Monk,et al.  Age-related differences in recovery from simulated jet lag. , 1992, Sleep.

[25]  S. Strogatz,et al.  Bright light resets the human circadian pacemaker independent of the timing of the sleep-wake cycle. , 1986, Science.

[26]  S. Daan,et al.  Bright morning light advances the human circadian system without affecting NREM sleep homeostasis. , 1989, The American journal of physiology.

[27]  Entrainment of circadian rhythms with 26-h bright light and sleep-wake schedules. , 1990, The American journal of physiology.

[28]  R. Kronauer,et al.  Exposure to bright light and darkness to treat physiologic maladaptation to night work. , 1990, The New England journal of medicine.

[29]  Peter Knauth,et al.  Re-entrainment of body temperature in field studies of shiftwork , 1981 .

[30]  H. Illnerová,et al.  Early morning bright light phase advances the human circadian pacemaker within one day , 1991, Neuroscience Letters.

[31]  T Akerstedt,et al.  Inversion of the sleep wakefulness pattern: effects on circadian variations in psychophysiological activation. , 1977, Ergonomics.

[32]  T. Åkerstedt,et al.  Sleepiness as a consequence of shift work. , 1988, Sleep.

[33]  C. Eastman,et al.  Circadian rhythms during gradually delaying and advancing sleep and light schedules , 1993, Physiology & Behavior.

[34]  A. Samel,et al.  Influence of Melatonin Treatment on Human Circadian Rhythmicity before and after a Simulated 9-Hr Time Shift , 1991, Journal of biological rhythms.

[35]  A. Lewy,et al.  Antidepressant and circadian phase-shifting effects of light. , 1987, Science.

[36]  K E Klein,et al.  A model for prediction of resynchronization after time-zone flights. , 1983, Aviation, space, and environmental medicine.

[37]  C A Czeisler,et al.  Light exposure induces equivalent phase shifts of the endogenous circadian rhythms of circulating plasma melatonin and core body temperature in men. , 1991, The Journal of clinical endocrinology and metabolism.