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Profils d'exposition à la lumière chez les types du matin et les types du soir
| Content Provider | Semantic Scholar |
|---|---|
| Author | Goulet, Geneviève |
| Copyright Year | 2007 |
| Abstract | Previous studies on chronotypes and known mechanisms of circadian entrainment by light suggest that daily light exposure could play a role in the establishment of a circadian type. In this study, ambulatory monitoring was used to measure 24-h light exposure in 12 moming-type (M-types) and 12 evening-type (E-types) subjects for 7 consecutive days. The circadian phase ofeach subject was then estimated in the laboratory using salivary melatonin concentration and the core body temperamre. On average, M-types showed more minutes of daily bright light exposure than E-types. As expected, M-types were exposed to more light in the moming than E-types and that the reverse was true in the late evening. However, there was no signiflcant difference for the light profiles in relation to circadian phase for the entire group and for the sub-group of M-types and E-types with different sleep schedules but similar circadian phases. These resuits suggest that the circadian pacemaker of those M-types and E-types was similarly entrained to the light-dark cycle they usually experience. By contrast, the sub-groups of Mtypes and E-types with very early or very late circadian phases showed large differences in their profiles of light exposure in relation to their circadian phase. This observation suggests that in these individuals, early or late circadian phases are related to relatively short and long circadian periods, and that a phase-delaying profile of light exposure in M-types and a phase advancing profile in E-types are necessary in order to assure a stable entrainment to the extemal 24-h day. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | https://papyrus.bib.umontreal.ca/xmlui/bitstream/handle/1866/17019/Goulet_Genevieve_2006_memoire.pdf?isAllowed=y&sequence=1 |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
