Research

Hormonal

Sleep is an actively generated state by the central nervous system, regulated by homeostatic and circadian processes, rather than a passive loss of wakefulness.

Understand that sleep is an active biological process. Disrupting this active process (e.g., through poor sleep hygiene or disorders) has significant consequences because the brain is actively working to regulate states.

StrongSupportsVERY_HIGH confidence
Sleep is not merely the passive loss of wakefulness. Sleep states are actively generated by the central nervous system (CNS). Sleep is homeostatically regulated and temporally organized into distinct phases.
Ralph Lydic et al. · Anesthesiology · 2005

Why this rating

Based on 40 years of research and multiple preclinical/clinical studies cited.

Source

Sleep, Anesthesiology, and the Neurobiology of Arousal State Control

Ralph Lydic et al. · Anesthesiology · 2005

DOI 10.1097/00000542-200512000-00024

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DOI resolved against Crossref · corpus check 2026-06-10

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