PSYCH 202 Lecture Notes - Lecture 19: Circadian Rhythm, Suprachiasmatic Nucleus, Optic Chiasm
Document Summary
During a typical night of sleep, when is our neural activity most likely to be synchronized: more often earlier in the night (relative to later in the night) when we are in deep sleep. False: more often later in the night (relative to earlier in the night) when we are dreaming, throughout the night, whenever our muscles are paralyzed. It may be synchronized at any time; neural activity is unpredictable through a night of sleep. Daily rhythms and our internal clock: circadian rhythm = "about a day" Cluster of cells within the hypothalamus: critical for maintaining the 24 hour cycle, daily rhythm, light matters. If you take away light cues (constant dim light), many animals have a natural circadian rhythm (about 25 hours a day) which is why the activity gets pushed an hour each day. Free-running period: our own natural cycle independent of external cues.
