The primary consequence of night shift work is a misalignment of the endogenous circadian pacemaker with the inverted sleep-wake cycle. This study evaluated the efficacy of a judicious schedule of light exposure on circadian adaptation to night work. Fifteen night shift workers (mean age +/-S.E.M.: 41.8 +/- 1.8 years) were studied for 3 weeks in their work environments under one of two experimental conditions. Treatment group participants underwent an intervention including bright light in the workplace, while control group participants were studied in their habitual light environments. The efficacy of the intervention was evaluated in the laboratory via constant routines. Following the intervention, treatment group subjects displayed a mean phase delay of (+/-S.E.M.) -9.32 +/- 1.06 hours and full entrainment to the night-oriented schedule while control group subjects displayed a phase delay -4.09 +/- 1.94 hours and a partial entrainment (F(1,30) = 11.33, p = 0.002). The results of this study suggest a means of alleviating the difficulties associated with night shift work with control of the overall pattern of light exposure.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.31243 |
| Date | January 2001 |
| Creators | James, Francine O. |
| Contributors | Boivin, Diane B. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Science (Department of Psychiatry.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001804651, proquestno: MQ70439, Theses scanned by UMI/ProQuest. |
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