Delayed Sleep is a sleep disorder where the major sleep episode is delayed by two or more hours of the regular bedtime which causes difficulty in awakening at the desired time, delayed sleep phase is a neurological sleep disorder which is common in teenagers.
People with this delayed sleep phase have a natural inclination to go to bed later and wake up later than what is typically considered normal. It is the opposite of advanced sleep phase, in which people go to bed and wake up earlier than normal.
Delayed sleep phase is the main reason for 10% of all chronic insomnia cases; Delayed sleep phase syndrome is most commonly referred to as night owls.
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