Definition: Advanced Sleep Phase Syndrome or ASPS is a disorder of your body's circadian rhythm. Our bodies have a natural internal clock or circadian rhythm that govern when we fall asleep and how long we need to sleep. If this balance is altered, you may suffer from a sleep disorder like ASPS, feel fatigued, experience insomnia or suffer from sleeping problems or sleeplessness. ASPS causes people to feel fatigued during the evening. It is a circadian rhythm sleep disorder that is more commonly found among women than men. Often the use of bright lights that mimic the light of the sun can help reduce feelings of tiredness in the early evening to help patients with this chronic sleep disorder.
Also Known As: circadian rhythm sleep disorder, ASPS