title: Diurnal fluctuation of time perception under 30-h sustained wakefulness.
abstract: Previous studies have reported that time perception in humans fluctuates over a 24-h period. Behavioral changes seem to affect human time perception, so that the fluctuation in human time perception may be the result of such changes due to self-determined activities. Recently, we carried out a study in which a healthy human cohort was asked to perform simultaneously loaded cognitive tasks under controlled conditions, and found that time perception decreased linearly from morning to evening. In addition, the variations in time perception were not a consequence of behavioral changes. It remains to be elucidated whether diurnal variations in time perception are a consequence of circadian rhythm or of some homeostatic changes that are attributable to accumulated wake time. The effects of circadian rhythm on time perception were investigated in eight healthy young male volunteers by conducting 10-s time production tasks under 30-h constant-routine conditions. Core body temperature and serum melatonin and cortisol levels were measured during the course of the study. Produced time exhibited a diurnal variation and was strongly correlated with circadian variations in core body temperature and serum melatonin levels. These results suggest that human short-term time perception is under the influence of the circadian pacemaker.
authors.affiliation: Department of Psychophysiology, National Institute of Mental Health, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira 187-8533, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Kuriyama
authors.forename: Makoto
authors.initials: M
authors.lastname: Uchiyama
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Suzuki
authors.forename: Hirokuni
authors.initials: H
authors.lastname: Tagaya
authors.forename: Akiko
authors.initials: A
authors.lastname: Ozaki
authors.forename: Sayaka
authors.initials: S
authors.lastname: Aritake
authors.forename: Kayo
authors.initials: K
authors.lastname: Shibui
authors.forename: Tan
authors.initials: T
authors.lastname: Xin
authors.forename: Li
authors.initials: L
authors.lastname: Lan
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Kamei
authors.forename: Kiyohisa
authors.initials: K
authors.lastname: Takahashi
mesh_terms: D000328:Adult; D001831:Body Temperature; D002940:Circadian Rhythm / Q000502:physiology*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D008550:Melatonin / Q000097:blood; D010147:Pain Measurement; D012892:Sleep Deprivation / Q000503:physiopathology; D013998:Time Perception / Q000502:physiology*; D014851:Wakefulness / Q000502:physiology*
chemical_list: D008550:Melatonin; D006854:Hydrocortisone