The article you requested is
The Neurotransmitters of Sleep
J Clin Psychiatry 2004;65(suppl 16):4-7
© Copyright 2014 Physicians Postgraduate Press, Inc.
The part of the brain most important in regulating sleep duration is the hypothalamus. Certain
groups of hypothalamic neurons and adjacent groups of basal forebrain neurons produce the neurotransmitter
γ-aminobutyric acid (GABA). Projections of these GABA neurons inhibit the firing of
cells involved in wakefulness. Several groups of neurons have been shown to be inhibited by this
action—including neurons containing histamine, norepinephrine, serotonin, hypocretin, and glutamate—and this inhibition promotes sleep. Hypocretin (also called orexin) was discovered in 1998,
and its role in sleep and narcolepsy was identified in 2001. Other as-yet undiscovered transmitters are
undoubtedly involved in sleep control. The transmitters discussed in this article have been the most
thoroughly studied, and many aspects of the role of each of these transmitters in relation to sleep are
reasonably well understood.