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Module 24: Sleep, Dreams, and Body Rhythms

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consciousness
Awareness of yourself and your environment.
pseudoscientific claim
Any assertion that is not based on science, even though in some circumstances attempts are made to appear scientific.
biological rhythms
Periodic psychological fluctuations.
circadian rhythms
Biological rhythms that occur approximately every 24 hours.
circadian
What kind of biological rhythm is the sleep-wake cycle?
ultradian rhythms
Biological rhythms that occur more than once each day.
ultradian
What kind of biological rhythm are the sleep stages?
infradian rhythms
Biological rhythms that occur once a month or once a season.
infradian
What kind of biological rhythm is the menstrual cycle?
(William) Dement
Sleep researcher who coined the term "rapid eye movement" (REM).
melatonin
Hormone that helps regulate daily biological rhythms.
EEG (electroencephalograph)
Machine that amplifies and records waves of electrical activity that sweep across the brain's surface; electrodes placed on the scalp measure these waves.
REM (rapid eye movement) sleep
Recurring sleep stage during which vivid dreams commonly occur; also known as "paradoxical sleep", because muscles are relaxed but other body systems are active.
insomnia
Recurring problems in falling asleep or staying asleep.
sleep apnea
Sleep disorder characterized by temporary cessations of breathing during sleep and consequent momentary reawakenings.
narcolepsy
Sleep disorder characterized by uncontrollable sleep attacks; the sufferer may lapse directly into REM sleep, often at inopportune times.
somnambulism
Sleepwalking, which usually starts in the deeper stages of non-rapid eye movement (N-REM) sleep; the sleepwalker can walk and talk and is able to see but rarely has any memory of the event.
night terrors
Sleep-related problem characterized by high arousal and an appearance of being terrified; unlike nightmares, occurs during Stage 4 sleep, occurs within 2 or 3 hours of falling asleep, and are seldom remembered.