1. A model of how alternating activity of brain stem and hypothalamic neurons may influence the different states of consciousness. In this model, wakefulness and REM sleep are at opposite extremes. When the activity of norepinephrine- and serotonin-containing neurons (locus coeruleus and raphé nuclei) is dominant, there is a reduced level of activity in acetylcholine-containing neurons in the pontine reticular formation leading to wakefulness. The reverse of this pattern leads to REM sleep. A more even balance in the activity of these groups of neurons is associated with NREM sleep. Increases in GABA and decreases in histamine promote NREM sleep via deactivation of the thalamus and cortex. Wakefulness occurs when GABA is reduced and histamine is released. (From Widmaier EP, Raff H, Strang KT: Vander's Human Physiology, 11th ed. McGraw-Hill, 2008.)
Source: Chapter 14. Electrical Activity of the Brain, Sleep—Wake States, & Circadian Rhythms, Ganong's Review of Medical Physiology, 24e
Citation: Barrett KE, Boitano S, Barman SM, Brooks HL. Ganong's Review of Medical Physiology, 24e; 2012 Available at: Accessed: October 30, 2017
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