PSYA01H3 Chapter Notes - Chapter 5: Suprachiasmatic Nucleus, Ultradian Rhythm, Non-Rapid Eye Movement Sleep
Document Summary
5. 1: biological rhythms of consciousness: wakefulness and sleep. Biological rhythms are patterns that cycle within days, weeks, months, or years. Infradian rhythm: occurring over a longer period of time than a day (period). Ultradian rhythm: occur very frequently (hr, urination, some hormones). Circadian rhythms: internal daily cycles (24hrs) of physiological processes. Suprachiasmatic nucleus (scn) of hypothalamus deals w/ daylight-nervous and endocrine system interactions (pineal gland releases melatonin in low light). Entrainment: biological rhythms synchronized w/ external cues (light, temp). We tend to be awake during the day and asleep during darkness. Endogenous rhythms: biological rhythms independent of external cues. Polysomnography: objective measurements examining physiological variables during sleep (measured w/ electroencephalogram (eeg)). Electroencephalogram (eeg): device that measures brain waves using sensors attached to the scalp. Output of eeg is in waveform, can be described by frequency and amplitude. Beta waves, (high frequency, low-amplitude waves) = alert. Stage 1: theta waves, breathing, blood pressure and hr decreased, still perceive sounds (10-15 min).
