Relevance of sleep neurobiology for cognitive neuroscience and anesthesiology

Althoughgeneral anesthetics areused for approximately 21millionpatients per year in the United States,1 the molecular and cellular mechanisms by which anesthetics produce loss of waking consciousness are poorly understood. The complexity of consciousness and relatively imprecise clinical signs that are used to evaluate the depth of anesthesia are significant limitations for the study of consciousness. Recent advances in sleep neurobiology continue to enhance the understanding of different physiological traits that define altered states of consciousness. The original hypothesis2 that neural networks that evolved to generate sleep are preferentially modulated by anesthetic drugs has been supported by multiple lines of evidence.3–9 These data demonstrate that sleep neurobiology can contribute to understanding the mechanisms by which anesthetics cause loss of consciousness. The goal of this chapter is to selectively review the neurobiology of sleep and wakefulness in relation to anesthesia-induced loss of consciousness.