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Key Terms

15.1 What Are Circadian Rhythms?

Chronobiology, circadian, ultradian, circatidal, infradian, circannual, circalunar, rhythm, period, phase, phase difference, amplitude, mesor, frequency, endogenous, exogenous, free running, entrainment, chronotype, sleep hygiene, subjective day, subjective night, phase response curve, dead zone, diurnal, nocturnal

15.2 Where Are Rhythms in the Brain?

suprachiasmatic nucleus, photoreceptors, intrinsically photosensitive retinal ganglion cells (ipRGCs), retinohypothalamic tract, melanopsin, arrhythmic, geniculo-hypothalamic tract, nonphotic, retinorecipient core, rhythmic shell, melatonin, transcription/translation feedback loop, clock genes, heterodimerize, translocate

15.3 Regulation of Sleep

Process C, Process S, homeostatic, glymphatic system, Polysomnography, electroencephalography, electrooculography, Rapid Eye Movement Sleep (REM), electromyography, non-REM (NREM), Stage 1 non-REM, Stage 2 non-REM, Stage 3 non-REM, sleep spindles, delta sleep, slow wave sleep, delta waves, flip flop switch, insomnia

15.4 Disorders of Sleep and Circadian Rhythms

non-24 hour sleep-wake disorder, narcolepsy, cataplexy, sleep paralysis, orexin, delayed sleep wake phase disorder, sleep inertia

15.5 Circadian Rhythms and Society

Daylight savings time, shift work, chronic sleep deprivation, chronic sleep deficiency, sleep hygiene, social jet lag, chronotherapeutics, chronomedicine
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