title: Eye movements during sleep in weightlessness.
abstract: The number of eye movements during sleep increased during the first sleep period in zero gravity but returned to normal by the second night. These rapid-eye-movement functions in flight may be the first variations of an oscillatory system. The ratio of the higher and lower eye movement frequencies oscillates within normal-gravity limits.
mesh_terms: D005133:Eye Movements; D006801:Humans; D012890:Sleep / Q000502:physiology*; D012895:Sleep, REM / Q000502:physiology; D013026:Space Flight; D014893:Weightlessness