Familial Advanced Sleep Phase Syndrome

Abstract

ADVANCED SLEEP phase syndrome (ASPS) is characterized by persistent advanced sleep onsets and awakenings that are earlier than desired.^1-3 Individuals with ASPS typically experience sleepiness in the early evening, when other people are active, and early morning awakening, when most are still sleeping. Therefore, individuals with ASPS sometimes find it difficult to maintain a normal social and work life. It has been postulated that ASPS is a circadian rhythm disorder in which the phase of the circadian rhythm of sleep and wake is advanced in relation to the "normal timing," which is synchronized, to the external environment.^2,3