Time-dependent effects of indoor lighting on well-being and academic performance.
Doctoral thesis, UCL (University College London).
Our knowledge of how changes in environmental lighting conditions affect non-visual processes in humans is less than adequate and based mainly on cross-sectional laboratory studies. Thus, the present research was designed to address the questions raised by the literature and clarify the non-visual effects of indoor lighting by carrying out two field studies at two different latitudes. During the period between the 8th of October 2008 and 10th of June 2009, the first field study was conducted in four similar classrooms of a junior school in Kent, U.K. The classrooms differed in the provision of artificial illumination and daylight. The study population consisted of fifty-six, fourth-grade students, aged between eight and nine years. Throughout the study, five main and five supplementary data collections were executed at approximately four-week intervals to assess participants’ sleep quality, mood and sleepiness by administering self-reports and also their diurnal melatonin and cortisol concentrations by collecting saliva samples. Additionally, data regarding participants’ performance on school examinations were collected to evaluate academic achievement. The results of the study revealed that natural light itself might be a potent factor in promoting the non-visual effects. Therefore, the second field study was conducted during the period between the 5th of January 2011 and 20th of January 2011 to verify the findings. The study was conducted in two similar classrooms of a junior school in Ankara, Turkey. The classrooms differed only in the provision of daylight. The study population consisted of seventy-nine, third-grade students, aged between eight and nine years. Throughout the study, two data collections were executed to assess participants’ sleep quality, mood and sleepiness by administering self-reports. Additionally, data regarding participants’ performance on school examinations were collected to assess academic progress. The second field study confirmed the findings form the previous field work. The participants who were exposed to more natural light at eye level reported significantly less daytime sleepiness and better sleep quality and overall mood. Moreover, their scholastic performance was comparatively better. Complementary information on the physiological, psychological and cognitive effects of indoor lighting that can be linked to our biophilic tendencies and Environment of Evolutionary Adaptedness is provided by the results of the two field studies.
|Title:||Time-dependent effects of indoor lighting on well-being and academic performance|
|UCL classification:||UCL > School of BEAMS > Faculty of the Built Environment > Bartlett School > Bartlett School of Graduate Studies|
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