The emotion has not been sufficiently digested and remains just under the surface, springing up for no apparent reason. Mental and emotional indigestion are the most common causes of insomnia. Some of us even grind our teeth while we sleep in an attempt to chew and digest recurring thoughts and emotions. The Contemporary Angle Modern explanations for insomnia range from overstimulation and stress to mucking up our waking-sleeping cycle. This is only another way of saying we are still attempting to digest these substances or events at the same time we are courting sleep.
Stress is another form of indigestion.
I don't know how to turn it off. Anxiety, worry, depression, unpleasant memories, and fears are the most common cause of sleeplessness. They seem to take on a life of their own and are determined to stay awake, even though it's way past bedtime. The third common cause of insomnia, one which has become prevalent only in modern times, is tampering with the normal cycle of sleeping and waking. This is a mechanical problem of sorts.