Updates Regarding Neurocircuits and Neurotransmitters Involved in the Regulation of Wakefulness

Sleep is a universal phenomenon that is observed not only in humans but also in birds, fishes, and flies even in simpler organisms such as worms also we spend about 8 hours each day in sleep which represents nearly one-third of our life. All these observations indicate the physiological importance of sleep. study of sleep mechanisms requires the first study of the mechanisms, neurocircuits, and neurotransmitters involved in the promotion of wakefulness. Observation of Von Economo in 1930 of patients affected by “encephalitis lethargica”, an epidemic that causes widespread and prolonged sleepiness most of the day, opened the door for the study of the brain regions responsible for wakefulness. Researchers recognized now many brain regions that are responsible for wakefulness and other brain regions responsible for the induction of different types of sleep. This review will try to discuss the most recent mechanisms and neural circuits involved in the promotion of wakefulness.