PSYB65H3 Study Guide - Midterm Guide: Sleep Disorder, Melatonin, Retina
Document Summary
Revision 10: biological rhythms & sleep (no required readings) Behavior is not simply driven by external cues from the environment. Circannual rhythm: yearly (e. g. migratory cycles of birds) Infradian rhythm: less than a year (e. g. human menstrual cycle) Ultradian rhythm: less than a day (e. g. eating cycle) Main pacemaker for circadian rhythms located above the optic chiasm. Neural route from a subset of cone receptors in the retina to the scn of hypothalamus. Allows light to entrain the rhythmic activity of scn. Ultimately helps regulate the release of melatonin. Decrease in body temperature, increase in growth hormone release. Dreaming does occur in nrem, but not as vivid as in rem sleep. Inconsistent nrem sleep of being a quiet, inactive period. Atonia: no tone; condition of complete muscle inactivity produced by the inhibition of motor neurons by sleep regions of our brainstem. Mechanisms that regulate body temperature stop working. Everyone dreams a number of time each night.
