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11 Cards in this Set

  • Front
  • Back
syncronization of biological rhythms with external cues, such as fluctuations in daylight
generated from within rather than by external cues
circadian rhythm
biological period within 24 hours
infradian rhythm
biological rhythm that occurs less than once a day
ultradian rhythm
a biological rhythm that occurs more frequently than once a day
suprachiasmatic nucleus
an area of the brain containing a biological clock that governs circadian rhythms
a hormone secred by the pineal glad; it is involved in the regulation of circadian rhythms
internal desynchronization
a state in which biological rhythms are not in phase with one another
seasonal affective disorder
controversial disorder in which a person experience depression during the winter and an improvement of mood in the spring
sleep apnea
stop breathing in sleep
lucid dream
a dream where the dreamer is aware of the dreaming