The sleep switch: hypothalamic control
of sleep and wakefulness
Saper CB, Chou TC, Scammell TE.
Dept of Neurology and Program in Neuroscience,
Harvard Medical School,
Beth Israel Deaconess Medical Center,
02215, Boston, MA, USA
Trends Neurosci 2001 Dec 1;24(12):726-31
More than 70 years ago, von Economo predicted a wake-promoting area in the posterior hypothalamus and a sleep-promoting region in the preoptic area. Recent studies have dramatically confirmed these predictions. The ventrolateral preoptic nucleus contains GABAergic and galaninergic neurons that are active during sleep and are necessary for normal sleep. The posterior lateral hypothalamus contains orexin/hypocretin neurons that are crucial for maintaining normal wakefulness. A model is proposed in which wake- and sleep-promoting neurons inhibit each other, which results in stable wakefulness and sleep. Disruption of wake- or sleep-promoting pathways results in behavioral state instability.