title: The presence or absence of light during flotation restricted environmental stimulation: effects on plasma cortisol, blood pressure, and mood.
abstract: This study examined the effect of light on relaxation associated with flotation restricted environmental stimulation therapy (REST), as measured by plasma cortisol, mean arterial pressure, and psychometric parameters. Twenty-one subjects were paired by baseline cortisol levels into two groups: one experiencing flotation REST in the presence of light (REST-L) and one experiencing flotation REST in the absence of light (REST-D). Subjects were 15 male and 6 female students aged 22-28 in normal health who had not experienced REST. Repeated flotation REST (8 sessions) either with light or without light was associated with a decrease in plasma cortisol and a decrease in mean arterial pressure, with no differences in effectiveness between groups. The psychometric assessment of mood, using the POMS scale, before and after sessions 1 and 8 revealed mood state improvement in both REST-L and REST-D groups. These data suggest that the presence of light did not compromise the flotation REST experience, as evidenced by the lack of difference between REST-L and REST-D groups.
authors.affiliation: Department of Physiology, Medical College of Ohio, Toledo 43699-0008.
authors.forename: J W
authors.initials: JW
authors.lastname: Turner
authors.forename: T
authors.initials: T
authors.lastname: Fine
authors.forename: G
authors.initials: G
authors.lastname: Ewy
authors.forename: P
authors.initials: P
authors.lastname: Sershon
authors.forename: T
authors.initials: T
authors.lastname: Freundlich
mesh_terms: D000328:Adult; D000339:Affect; D001794:Blood Pressure; D004780:Environment, Controlled; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D008029:Lighting; D008297:Male; D011594:Psychometrics; D011603:Psychophysiology; D012063:Relaxation / Q000502:physiology*
chemical_list: D006854:Hydrocortisone