ABSTRACT
Sleep problems, while reported even in the original description by James Parkinson (1) and subsequently by Charcot (2), are now better defined with the recent emergence of and progress in the field of sleep medicine. There are multiple reasons for sleep problems in patients with Parkinson’s disease (PD). Neuronal substrates of sleep may be affected in PD patients. Sleep is best understood in terms of its structural, neuronal, and neurochemical substrates. Several neurotransmitter systems are involved in sleep-wake functioning, including serotonin (dorsal raphe nuclei), norepinephrine (locus ceruleus), acetylcholine (pedunculopontine nucleus), and dopamine (striatonigral system, ventral tegmentum, and mesocorticolimbic system). In PD, neuronal loss occurs in the substantia nigra, locus ceruleus, and possibly in the dorsal raphe nuclei and pedunculopontine nucleus. This alteration in neuronal substrates may form the basis for sleep disturbances in patients with PD.
