Awakening and sleep are both necessary processes of physiological activities, and the human body can only carry out activities such as labor when it is awake; Sleep can restore the body's energy and physical strength, and maintain a good state of awakening. The maintenance of awakening state is the function of ascending excitation system in brainstem reticular structure. Sleep is the central active process. The ascending inhibitory system at the end of the brain stem acts on the cerebral cortex to counteract the ascending excitatory system, thus regulating the mutual transformation between sleep and awakening.