title: Enhancement of REM sleep during extraocular light exposure in humans.
abstract: This study examined the effects on sleep of light administered to an extraocular site. A 3-h photic stimulus was applied to the popliteal region during sleep in 14 human subjects. Each subject also underwent a control stimulus condition during a separate laboratory session. The proportion of rapid eye movement (REM) sleep during the 3-h light administration session increased by an average of 31% relative to the control condition. The frequency but not the duration of REM episodes was altered during light exposure, thereby shortening the REM/non-REM (NREM) cycle length. No other sleep stages were significantly affected during light administration nor was sleep architecture altered after the light-exposure interval. These results confirm that extraocular light is transduced into a signal that is received and processed by the human central nervous system. In addition, they expand to a novel sensory modality previous findings that REM sleep can be enhanced by sensory stimulation.
authors.affiliation: Laboratory of Human Chronobiology, Department of Psychiatry, Weill Medical College of Cornell University, White Plains, New York 10605, USA. pjmurphy@med.cornell.edu
authors.forename: P J
authors.initials: PJ
authors.lastname: Murphy
authors.forename: S S
authors.initials: SS
authors.lastname: Campbell
mesh_terms: D002940:Circadian Rhythm / Q000502:physiology / Q000528:radiation effects; D006801:Humans; D007717:Knee / Q000528:radiation effects*; D008027:Light; D011930:Reaction Time / Q000528:radiation effects; D012016:Reference Values; D012894:Sleep Stages / Q000528:radiation effects; D012895:Sleep, REM / Q000528:radiation effects*; D013997:Time Factors; D014851:Wakefulness / Q000528:radiation effects