First 328 words of the document:
The consequences of disrupting biological rhythms
Jet Lag: (when sleepwake cycle isn't synchronised with time zone) Travelling west to east is worse as you're
gaining time and haven't reached sleep gate yet.
Klein et al (1972) confirmed this and found that one day per time zone crosses was needed for full
Jet lag not always easy to recover from
Recovering from jet lag more quickly: take melotonin 2 hours before wanting to go to sleep.
Schwartz et al (1995) American baseball teams. West coast teams who travelled east had significantly
fewer wins than east coast teams travelling west. Suggests jet lag decreases performance. Extraneous
variables/ might not be travelling that causes losses.
Can't generalise fit young men, jet lag might have a worse effect on others.
Shift Work: sleepwake cycle not synchronised with day/night. Changing shift patterns means that sleepwake
cycle has to constantly adjust.
Industrial accidents occur between 1am and 4am. Lorry accidents occur between 4am and 7am. Takes
about a week to adjust to a new shift. Suggests: decreases performance/ awareness. Increases danger.
Blakemore (1988) 3 weeks schedule for workers: 1st week = day shift/ 2nd week= night shift/ 3rd shift =
evening shift. Most common shift pattern animals who are subjected have increased heart disease.
Sleep gate has to shift, not natural. Tired, worse skill and performance in workers.
Unethical, but justified. Can use to develop better shift patterns. Biological similarities to animals can
generalise, but humans have more awareness of shifts, animals are stressed.
Czeisler et al (1982) Proposed to rotate shifts forward in time. Tested at same plant as Blakemore
workers felt better and less tired at work. Management reported increased productivity and fewer errors.
Better because: easier to sleep later than earlier field exp C&E. Might perform better since they're