This article summarizes sleep disturbances in a variety of neurodegene
rative diseases, including Parkinson's disease, multiple system atroph
y, and amyotrophic lateral sclerosis. Sleep complaints in these condit
ions include insomnia, hypersomnia, abnormal motor activity and behavi
or during sleep, sleep-related breathing problems, and circadian rhyth
m sleep disturbances. Clinical examination followed in selected cases
by polysomnographic, multiple sleep latency, and other laboratory test
s is essential for correct diagnosis and treatment of these sleep dist
urbances.