Individuals with<unk>  report being unable to stay awake until conventional bedtime, falling asleep early in the evening, and being unable to stay asleep until their desired waking time, suffering early morning insomnia. When someone has<unk>  their melatonin levels and core body temperature cycle hours earlier than an average person. These symptoms must be present and stable for a substantial period of time to be correctly diagnosed.
Advanced sleep phase disorder
Delayed sleep phase disorder
Circadian rhythm sleep disorder
Non-24-hour sleep–wake disorder
Shift work sleep disorder
Nightmare disorder
Rapid eye movement sleep behavior disorder
Idiopathic hypersomnia