Alcohol acts as a sedative that interacts with several neurotransmitter systems important in the regulation of sleep. Acute administration of large amounts of alcohol before bedtime results in decreased latency to fall asleep and changes in sleep architecture early at night when blood alcohol levels are high, and disturbed, poor quality sleep later at night.
Alcohol abuse and dependence are associated with chronic sleep disturbances, lower slower than normal sleep waves, and faster than normal eye movement, which may persist into periods of abstinence and play a role in relapse. This chapter outlines the evidence for acute and chronic alcohol effects on sleep architecture and the sleep electroencephalogram, the evidence for tolerance to repeated administration, and possible underlying neurochemical mechanisms for the effects of alcohol on sleep.
Handbook of Clinical Neurology, Chapter 24: Alcohol and the sleeping brain
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