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Abstract

Article Abstract
Excessive arousal (both psychological and physiologic) may be the main factor in the etiology of insomnia. Hyperarousal may be the final common pathway in moving the sleep/wake balance toward excessive wakefulness and away from sleep. Psychiatric and psychological factors play a major role in increasing this hyperarousal. Most clinical forms of depression and anxiety disorders are clearly associated with severe insomnia, but stress, learning, and conditioning are also crucial parameters related to insomnia. Depression, anxiety, and stress appear to cause insomnia, not vice versa. The vulnerability of an individual to a specific stress may be a mediating variable, explaining why some persons develop severe insomnia when stressed, while others do not.