Insomnia overview: epidemiology and pathophysiology
Insomnia, the most common sleep disorder with 30% to 40% of adults reporting the symptoms. It is a complex interaction between psychological cognitive state and homeostatic mechanisms. 5 progressive stages include: wakefulness, relaxed wakefulness, light sleep, deep or slow-wave sleep and dreaming. Brain cortical activity is low during the first stages, but highly active during the last one. Sleep-wake cycle has a switch, which permits one to either be awake or asleep, but not both, at the same time. Homeostatic factors are responsible for the drive for sleep. Predisposing factors include genetics and personality traits. Another trigger is typically stressful life events. Check the details by the link.