Sleep disorders are common and affect sleep quality and quantity, leading to increased morbidity. Patients with sleep disorders can be categorized as those who cannot sleep, those who will not sleep, those with excessive daytime sleepiness, and those with increased movements during sleep. Insomnia, defined as difficulty initiating or maintaining sleep that results in daytime impairment, is diagnosed using history findings and treated with cognitive behavior therapy, with or without sleep hypnotics.Lesion and pharmacological studies show that sleep and wakefulness are controlled by multiple neuronal systems using different chemical neurotransmitters such as glutamate,acetylcholine, noradrenalin, dopamine, serotonin, histamine, adenosine, γ-amino-n-butyric acid (GABA), and orexin.

References

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