Circadian rhythms

• Circadian rhythms-

  -Type of biological rhythm, subject to 24 hour cycle

  -Regulates number of body process such as sleep wake cycle and changes in core body temperature
• Biological rhythms -

  Rhythms are regulated by 2 things:

  1)Endogenous pacemakers (internal body clock)

  2)Exogenous zeitgebers (light)
• Siffres cave study-

  -Performed an experiment where he spent 2 months in cave in Southern alps

  -He had adequate access to food and drink but no exposure to natural light or sound

  -Resurfaced mid september 1962, believing it to be mid August

  -His biological rhythm settled down to one that was beyond usual 24 hours
• Aschoff and Weber -

  -Group of ppts to spend 4 weeks in a WWII bunker, deprived of natural light

  -All but 1 of ppts displayed a circadian rhythm of 24-25 hours