Recent Advances in Research on the Amygdala Complex in Sleep and Anesthesia Awakening: A Hub for the Integration of Emotion and Arousal.

Abstract

The amygdala complex (comprising the lateral, central, and medial amygdala) has traditionally been regarded as playing a central role in emotional learning and fear memory. However, recent studies have revealed its critical functions in the regulation of sleep cycles and recovery from anesthesia. This review proposes a new theoretical framework that views the amygdala complex as an "emotion-arousal integration network" that integrates internal emotional states with external environmental demands to dynamically regulate overall arousal levels and states of consciousness. This review first outlines the neuroanatomy and cellular composition of the various subnuclei of the amygdala, then systematically elaborates on the role of the basolateral amygdala in the regulation of the physiological sleep-wake cycle, and explores its new role in promoting the recovery of consciousness during general anesthesia. Building on this foundation, the review further analyzes the complementary roles of the central and medial amygdala in sleep regulation, as well as how functional imbalances in the amygdala lead to sleep and emotional symptoms in conditions such as post-traumatic stress disorder. Finally, the review outlines potential clinical translation strategies based on amygdala circuits and neurochemical mechanisms, and discusses current research challenges and future directions.