Thorn, Lisa and Hucklebridge, Frank and Esgate, Anthony and Evans, Philip D. and Clow, Angela (2004) The effect of dawn simulation on the cortisol response to awakening in healthy participants. Psychoneuroendocrinology, 29 (7). pp. 925-930. ISSN 0306-4530Full text not available from this repository.
Bright light exposure after awakening has been shown to elevate cortisol levels in healthy participants. The present study examined the effect of dawn simulation (a treatment for seasonal affective disorder) on the cortisol response to awakening and mood. Twelve healthy participants were supplied with a dawn simulator (The Natural Alarm Clock, Outside In, Cambridge Ltd), a bedside light that increases in intensity prior to awakening to approximately 250 lux over 30 mins when an audible alarm sounds. A counterbalanced study was performed on 4 consecutive normal weekdays, two of which were control days (no dawn simulation) and two experimental (dawn simulation). Saliva samples were taken immediately on awakening then at 15, 30 and 45 minutes post awakening on all 4 study-days. Total cortisol production during the first 45 mins after awakening was found to be significantly higher in the experimental condition than in the control condition. Participants also reported greater arousal in the experimental condition and there was a trend for an association between increased arousal and increased cortisol secretory activity under dawn simulation. This study provides supportive evidence for the role of light and the suprachiasmatic nucleus in the awakening cortisol response.
|Uncontrolled Keywords:||Human, Saliva, Cortisol, Awakening cortisol response, Light, Dawn simulation|
|Subjects:||University of Westminster > Social Sciences and Humanities
University of Westminster > Science and Technology > Life Sciences, School of (No longer in use)
|Depositing User:||Users 4 not found.|
|Date Deposited:||25 Nov 2005|
|Last Modified:||04 Nov 2009 14:31|
Actions (login required)
|Edit Item (Repository staff only)|