Sleep neurophysiology in fragile X patients

Neurophysiological and neurochemical mechanisms underlying mental retardation and behavioral and emotional problems in the fragile X (fraX) syndrome are still poorly understood. In this study, the authors evaluated the sleep characteristics of a group of 9 fraX boys in order to obtain information on their neurophysiological mechanisms. A reduction in total sleep time and rapid eye movement (REM) sleep was found in the fraX patients together with an increase in the first REM latency. Slow-wave sleep was found to be increased. Moreover, an increase in twitch movements was also observed during REM sleep. A dysregulation of the cholinergic-monoaminergic system during sleep is hypothesized to occur in the fraX syndrome.