Minimizing Work Schedule Disruption with Bright Light.
Department of Psychiatry, Institute of Chronobiology, Cornell Medical Center, New York Hospital, White Plains, New York 1994 Sep:28 pages
The effects of bright light interventions on schedule adaptation to night work in middle aged individuals were investigated in a simulated shift work study. Twenty six subjects aged 40 to 60 years participated in the study. The subjects performed the Simulated Assembly Line Task during simulated night shifts. At midnight on day one, the first of three consecutive night shifts began. From midnight until eight the following morning the subjects worked individually at specially designed work stations. The Active Group received a 4 hour pulse of bright light (greater than 4000 lux) at the start of the first night shift from midnight to 4AM, followed by ambient room illumination, less than 100 lux, for the remainder of the first shift. On the two subsequent night shifts the group was exposed to illumination of about 1000 lux for the duration of each shift. The Control Group was exposed to normal ambient illumination of less than 100 lux during the night shifts. The subjects were in bed for 8 hours following breakfast after the night shift ended. They were not allowed to nap during the entire study. Results indicate that, although light was effective in resetting the circadian clocks of these subjects, there was little effect on measures of on duty alertness and performance, or on off duty sleep. The authors suggest that middle aged subjects may be less phase tolerant that young subjects. The usefulness of bright light interventions in shift work populations was discussed.
NIOSH-Grant; Grants-other; Shift-workers; Illumination; Shift-work; Sleep-disorders; Circadian-rhythms;
Human Alertness Research Ctr Inst for Circadian Physiology 677 Beacon Street Boston, MA 02215
Final Grant Report;
NTIS Accession No.
Other Occupational Concerns; Grants-other;
Department of Psychiatry, Institute of Chronobiology, Cornell Medical Center, New York Hospital, White Plains, New York
Institute for Circadian Physiology, Boston, Massachusetts