Content uploaded by Nastaran Shishegar
Author content
All content in this area was uploaded by Nastaran Shishegar on May 24, 2016
Content may be subject to copyright.
International Conference on “Health, Biological and Life Science” (HBLS-16) April 18-19, 2016 Istanbul, Turkey
151
Abstract— Recent studies show that the quality of the school
environment significantly influences students’ academic
performance. Among the many attributes of the school
environment, light is one of the most important ones. Lighting in
the classrooms has been subject of many studies for over a
century. In recent years, special attention has been given to the
impact of natural light on learning in the classrooms as light has
physiological, psychological and behavioral influences on school
children as well as workers. A multitude of surveys have indicated
also that daylight impacts the health and performance of children
in schools and that students’ health, satisfaction, attention, and
consequently performance are improved in the classrooms with
the help of natural light. This paper discusses the current
literature and evidence to evaluate the impacts of natural light on
students’ scholastic performance. Issues of timing and exposure to
daylight are also discussed in regard to health, alertness and
performance at school.
Keywords—Daylighting, Morning Sunlight, Students, Health,
Alertness
I. INTRODUCTION
Among many elements that impact building occupants, light
seems to have the most important impact. Light is an essence
for humans and it is known that has physical, physiological, and
psychological influences [1].
In the early part of the 20th century, natural light was the
primary source of building illumination. In a short span of a
couple of decades, electric lighting sources became the primary
source of illumination because of convenience mostly. In recent
years, energy conservation and environmental concerns have
changed those practices and brought daylighting is becoming
once again an important factor in building design [2]. For
decades, an appropriate lighting design was based on the
concept that it should meet the needs of the occupants
especially in terms of visual task performance as well as,
economical concerns. However, recent connections between
building occupants’ health and wellbeing and lighting has
brought the concept of lighting quality to the forefront of
environmental concerns in architectural design [1]. Recent
studies have proven that there is a correlation between lighting
F. N.Shishegar, Master of Architecture student at Illinois School of
Architecture, University of Illinois at Urbana-Champaign, USA (e-mail:
nshish2@illinois.edu).
S. M. Boubekri, Associate professor at Illinois School of Architecture,
University of Illinois at Urbana-Champaign, USA (e-mail:
Boubekri@Illinois.edu).
and humans’ performance and health. Light does not only
provide visual information but also constitutes a powerful
modulator of non-visual functions including state of alertness,
mental focus, and cognitive performance [3].
Light is also an important learning ingredient in the
classroom environment, as it appears to have strong influences
on cognition and learning. Research on electric lighting in the
classroom environment has received some attention over the
last few decades but research on the impact of natural light on
students in the classroom has been somewhat scarce [4]. The
very few studies in this area seem to show that windows and
daylight can enhance students’ physical and psychological
health, influence their mood, behavior and learning [5], [6]. Our
study presents a comprehensive review of recent work that
explored the relationship between daylight and students’ and
workers’ health and performance. In this regard, the influence
of morning sunlight on circadian system, brain activity and
alertness of students are discussed.
II. SPECTRAL CHARACTERISTICS OF DAYLIGHTNG AND
ARTIFICIAL LIGHTING
According to the Illuminating Engineering Society
“Daylighting refers to the art and practice of admitting beam
sunlight, diffuse skylight, and reflected light from the exterior
into a building to contribute to lighting requirements and
energy saving through the use of electric lighting controls”
[7].
Compared to natural light, artificial lighting provides a very
constant radiation field which could be turn on or off simply.
Spectral quality is a complicated term which is used to show
how warm or cool a light is (Correlated Color Temperature of
light, CCT) as well as the shift of color (Color Rendering
Index, CRI). Generally, the higher the CRI means the color of
an object will appear more accurately [8]. The sun generates a
broad spectrum of light in order to provide sufficient
wavelength for all people to recognize most colors. Therefore,
it is considered that the light from the sun has a CRI of 100
which is the maximum value a light can achieve [9].
Various studies have demonstrated the multitude of benefits
that daylight has in terms of its spectral qualities such as in the
generation of Vitamin D through our skin. In fact, this is the
nature of the light spectrum in sunlight that makes it unique in
improvement of human health and it could not be found in
electric lighting [8].
Natural Light and Productivity: Analyzing the Impacts of
Daylighting on Students’ and Workers’ Health and
Alertness
N. Shishegar, M. Boubekri
International Conference on “Health, Biological and Life Science” (HBLS-16) April 18-19, 2016 Istanbul, Turkey
152
III. DAYLIGHTING, HUMAN BODY, AND HEALTH
Humans are affected both physically and psychologically by
light. These effects are less quantifiable and consequently the
benefits of daylighting have been somewhat overlooked over
the years. Physically, light affects our bodies in two ways:
natural light interacts with our skin through photosynthesis and
produces vitamin D. Vitamin D facilitates calcium absorption
which strengthens our bones. Underexposure to sunlight causes
vitamin D deficiency which can result in a range of illnesses. In
the seventeenth century, vitamin D deficiency was attributed to
rickets. Between 1910 and 1930, researchers determined that
inadequate levels vitamin D causes abnormal bone frailty a
consequence of insufficient calcium in bones [8], [10].
In the second way, light is able to affects our metabolism and
our endocrinal and hormonal systems through our vision
system [8]. Recent studies have demonstrated that in addition to
illuminate task and provide visual comfort, natural light has
also an important non-visual impact on our biological processes
and is essential in synchronizing our circadian clock, in
stimulating blood circulation, and controlling the levels of
many of our hormones [11], [12].
For more than 150 years, scientists considered the rods and
the cones to be the only photoreceptors in the eye. In 2002, a
new stream in photobiology research –– demonstrated that
there is an alternative pathway from eyes to the brain. The new
pathway regulates various interactions between biological
functions and external luminous stimuli. New type of
photoreceptor in the retina of mammals was identified. This
new photoreceptor, a specific subtype of retinal ganglion cells,
describes the mechanism that light and darkness impact
humans’ biological systems [13].
Studies have also demonstrated that light influences health,
well-being, alertness, and sleep quality. Natural light affects
circadian rhythm, which is responsible for synchronizing
human’s body internal clock. Circadian rhythmicity in humans
is responsible for many cognitive processes such as attention,
executive functions and also memory. Generally, in cognitive
performance, circadian rhythms are influential through a
gradual enhancement during the biological day and a gradual
decline in performance during the biological night [3]. Light is
able to influence cognitive performance through its
synchronizing /phase-shifting impacts on the circadian clock.
As a results, exposure to natural light impacts brain cognitive
performance.
Impact of building daylighting on sleep quality has been
investigated in a limited number of studies. All of these studies
show that natural light exposure improves sleep quality of
building occupants such as office workers and students
[14]-[16]. Friborg and colleagues examined the role of several
self-regulatory variables such as mood, fatigue, behavioral
habits, as well as psychological self-regulation as moderators of
seasonality in sleep timing on 162 young participants in
Norway. The results of this study indicate that not only sleep
timing is delayed during the dark period (December) compared
to seasons with brighter photoperiods (September and March),
but also that seasonal sleep effects are followed by depression,
and to a lesser extent anxiety and fatigue. Inadequate daylight
reduced the circadian cycle [16]. As a result, melatonin is
secreted at the wrong times of the day causing chronic fatigue,
depression, and possibly other illnesses [1], [17].
Moreover, lighting affects mood and attitude. Daylighting
has been associated with improved mood, with an enhancement
of morale, lower fatigue, and reduced eyestrain. The seasonal
depression is considered as obvious evidence to prove the
relationship between natural light and human endocrinal
system. The seasonal depression usually found among people
living in northern latitudes is referred to as Seasonal Affective
Disorder (SAD) which describes the depression caused by lack
of daylight [8]. According to Avery and colleagues, more than
10% of the population of Finland and about 6% of that of the
United States suffer from this seasonal disorder [18].
Furthermore, many studies indicate that daylighting
enhances mental performance and decreases aggressive
behavior as well as depression [19]. Another advantage of
daylighting is its variability in its intensity throughout the day
and the seasons. In a research conducted by Hoffman and his
colleagues on the impact of different lighting conditions on
subjective mood in an experimental office showed that varying
lighting levels has a potential advantage for office workers as
far as their subjective mood [20]. Another important
psychological aspect resulting from daylighting is meeting our
need for contact with the outside world through daylight
apertures in buildings [21]. In this regard, daylighting has a
natural healing effect by its provisions of view to the outside
world. Daylighting can enhance a connection to nature and
directly improve the mood of the building occupants [22]. As
sown in TABLE 1 there is a multitude of physiological and
psychological benefits resulting from building daylighting.
TABLE I: NATURAL LIGHT AND HUMAN BODY
Natural light and human body
Physically
Psychologically
Improve
Decrease
Improve
Decrease
Vitamin D
Cancer
Possibility
Mood
Depression
Visual System
Abnormal
Bone
Formation
Mental
Performance
Stress
Circadian
Rhythms
-
Alertness
Sadness
Sleep Quality
-
Brain activity
Violent
Behavior
IV. DAYLIGHTING AND PRODUCTIVITY
Many studies have attempted to correlate daylighting to an
improved productivity at the workplace. Boyce et al. defined
the productivity of an individual, or an organization, as the
ability of improving work production by increasing in either
quantity and/or quality of the product or service to be delivered
[23]. According to these authors there are three routes by which
lighting conditions can affect the performance of individuals:
(1) visual system, (2) circadian system, (3) and perceptual
system. Lighting conditions determines the capabilities of
visual system. As mentioned in previous paragraphs, the
circadian system is also influenced by light/dark cycle which is
related to lighting conditions directly [23]. Fig. 1 shows a
International Conference on “Health, Biological and Life Science” (HBLS-16) April 18-19, 2016 Istanbul, Turkey
153
conceptual framework for considering the relationship between
lighting conditions and human performance through the visual
system, circadian system and perceptual system [23].
Fig. 1. A conceptual framework setting out the routs by which lighting can
influence human performance. The arrows indicate the direction of the effects
[23].
Fig.2. Model of the impacts of light and lighting change on profitability in
the industrial environment [24].
Juslen and Tenner, present another conceptual model of the
influence of light and lighting condition changes on
productivity in the industrial environment [24]. This model is
shown in Fig. 2. The perspective behind this model is different
from that stated by Boyce et al. According to this study,
installing new lighting in the work environment affects the
performance of workers through several mechanisms. There are
at least 10 mechanisms that contribute to the enhancement of
people’s productivity including visual performance, visual
comfort, visual ambience, interpersonal relationships,
biological clock, stimulation, job satisfaction, problem solving,
the halo effect, and variability and changes in the environment
[24].
Other studies have evaluated the impact of natural light on
individuals’ productivity from other points of view such as
health, well-being, physical activity, motivation, achievements,
and etc. In the following paragraphs some of those studies will
be introduced.
Studies on the impacts of light on humans’ productivity date
back to 1920s. One of these early studies examined the impact
of lighting quality on silk weavers. In this study, Tennesen and
Cimprick [2] found out that people with views of natural
vegetation posed more attention during the work hours. The
view from windows is not the only important part of
daylighting techniques. Natural light increases attention and
alertness during the post-lunch dip and was shown to be helpful
in increasing alertness for mundane and repetitive tasks [21].
Another study conducted in the early 1990s showed that
employees of West Bend Mutual Insurance Company who
moved into a new building and who were provided with
personal control over their workstation environmental
attributes such as temperature, task lighting registered higher
performance overall compared to before the move. By moving
to a new building, the number of employees having a
workstation with a window view increased from 30% to 96%.
West Bend determined that compared to the old building, the
employees had a 16% increase in claims processing
productivity in the new building [19], [25].
Borisuit and colleagues evaluated the effects of daylighting
on office workers’ performance from the perspective of visual
comfort, alertness, and mood. The study was conducted on
twenty-five young subjects who spent two afternoons either
under electric light or daylighting conditions (without view
from the window). They found significantly higher visual
acceptance scores under daylighting than electric lighting
conditions, despite the lack of a direct outside views. While
subjective alertness and physical well-being decreased for both
lighting conditions in the course of the afternoon, subjects felt
sleepy earlier under electric lighting than daylighting. Physical
well-being became worse in the course of the afternoon under
electric lighting only. More visual comfort, alertness, and
well-being can be one of the indicators of office workers work
satisfaction and all of these factors enhance productivity as a
result [26].
Moreover, in another study, Boubekri and colleagues
examined the impact of daylight exposure on office workers’
productivity by considering subjective health, well-being, d
physical activity and sleep quality, all factors that have
significant influence on the productivity of individuals. Results
of this study indicate that office workers in offices without
windows reported poorer scores with respect to vitality,
physical activity and sleep quality in comparison to the group
with windows [14]. This same study revealed that office
workers with plenty of daylight throughout the day sleep on
average 46 minutes longer than their counterparts with no
daylight and windows. Other studies focused on absenteeism as
a gauge to measure productivity [27].
The fact that daylight seems to influence productivity in the
office setting could be extrapolated to the classroom
environment as well and one m ay hypothesize that daylighting
International Conference on “Health, Biological and Life Science” (HBLS-16) April 18-19, 2016 Istanbul, Turkey
154
influences students’ academic performance.
V. NATURAL LIGHT AND STUDENTS’ ACADEMIC
PERFORMANCE
The design of schools is to promote learning for children and
adults alike as well as optimize their physical and emotional
health. It should not be ignored that schools are among the most
crowded buildings most of the year and host young people.
Applying adequate daylighting techniques into the architecture
of a school contributes the occupants’ physical and emotional
health [28].
Students and teachers can benefit from integrating and
managing daylight properly. Saving energy, improved student
attendance, health and academic performance, and a less
stressful environment for students are only a few benefits of
adequate daylighting in educational environments [19]. Studies
show that teachers are happier when they have the ability to
control their environment. Healthy and happy teachers save
school money and have better performance in teaching [29]. In
contrast, a school with inadequate lighting design might demote
students’ ability of learning. Poor light spectral quality in
classrooms can create strain on students’ eyes and lead to a
decrease in information processing and learning ability as well
as higher stress levels in students [30].
Kuller and Lindsten studied children’s health and behavior in
classrooms with and without windows for an entire academic
year. They concluded that work in classrooms without windows
affected the basic pattern of the hormone cortisol, which is
related to stress, and could, therefore, have a negative effect on
children’s health and concentration. However, no direct
relationship was found between cortisol levels and student
performance and health [5], [28], [31]. In another study in
Sweden it was proved that observed behavior and circadian
hormone levels of elementary students in classrooms with
natural light stayed closer to expected norms in comparison
with students in classrooms with only fluorescent lighting [32].
Heschong and Mahone studied the impact of natural light
and students and found that the addition of natural light
improves student test score by up to 20% [32]. Taylor states
that students in classrooms with the most daylighting progress
20% and 26% faster in one year in math tests and reading tests
respectively compared to their counterparts in classrooms with
little or no natural light [33]. Another study conducted by Kim
et al. on daylight quality of educational facilities in high-rise
housing complexes in South Korea shows that daylight had an
influence on the quality of the educational environment, and
students’ learning performance [34].
Aggio et al. [35] evaluated the impact of light exposure on
the productivity of 229 students from the perspective of
physical activity and sedentary time (age mean = 8.8 years) in
Camden, UK. To investigate it, daily sedentary time, Moderate
and Vigorous Physical Activity (MVPA) and light exposure
were measured daily by using a tri-axial accelerometer with
ambient light sensor during the summer. The results of this
study illustrate that there are significant associations between
average daily light exposure and time sedentary and in MVPA.
Researchers concluded that average light exposure is positively
associated with time in MVPA and negatively associated with
sedentary time. Therefore, increasing daylight exposure might
be a useful intervention strategy for promoting physical activity
and consequently vitality and performance among young
Students [35].
Just like absenteeism in work environment, attendance is
another factor which could be considered a measure of
students’ performance. Schools that have integrated full
spectrum fluorescent or natural light show an increase in
student and teacher attendance when compared to traditionally
lit schools with lesser quality light fixtures. A study of the full
spectrum fluorescent Canadian schools reported that students
had an attendance increase of 3.2 to 3.8 more days per year than
students in traditional fluorescent lighting schools [19]. Durant
Road Middle School in Wake County school system in North
Carolina was especially designed to incorporate daylighting in
its classrooms. It reported the best health and attendance in the
entire school system and an attendance rate above 98%. The
school also claimed the lowest number of faculty health
absences in the area [19].
VI. IMPACT OF MORNING BRIGHT LIGHT ON STUDENTS’
ALERTNESS AND PERFORMANCE
It should be considered that different spectrums of sunlight
have various impacts on humans’ body and particularly eyes. In
fact, visual and non-visual effects of light on brain functions
and responses are dependent on the specific wavelength of the
light received through the eye. As a result, morning sunlight
with a short wavelength spectrum influences people’s body
differently compared to long wavelength of afternoon sunlight.
It was observed that 6.5 hours exposure to blue light (460-nm
monochromatic light) during the biological night decreases
subjective sleepiness and enhances auditory performance and
alertness compared with exposure to an equal photon density of
green light (555-nm monochromic light) [36]. These findings
show that the alerting impacts of ocular light exposure are
wavelength dependent and there is a greater sensitivity to short
wavelengths in the visible spectrum. It was also observed that
even a few tens of seconds of light exposure brings about
immediate and significant wavelength-dependent changes in
the brain [39]. According to Vandewalle, 50 seconds exposure
to blue light increases activity in the left hippocampus, left
thalamus, and right amygdala, as compared to green light [37].
Morning light plays an essential role in the synchronization
of metabolic rhythms to the 24h rotational cycle of the Earth.
Without regular daylight entrainment, the human circadian
clock would run on average on a 24h and 15-30 minutes cycle,
ultimately leading to a shift of the circadian pacemaker, and a
desynchronisation of our biological clock. The impact of early
morning sunlight on students’ circadian system has been
investigated by Figueiro and Rea [38, 39] in the outside
laboratory conditions. This study showed that lack of
short-wavelength light in the morning brings about 30 minutes
delay in circadian phase for 8th-grade students. Other studies
showed similar results under controlled laboratory conditions.
The findings of the controlled laboratory results confirm those
found in real settings of school environments. Circadian rhythm
is largely responsible for numerous cognitive processes such as
attention, alertness, sleep quality, mood, as well as memory.
International Conference on “Health, Biological and Life Science” (HBLS-16) April 18-19, 2016 Istanbul, Turkey
155
These are key ingredients in the learning processes. Exposure
to natural light in the classrooms seems to be essential in
improving students learning.
The impact of morning exposure to daylight was also
examined by Keis et al. [40]. The results of this study prove that
the blue-enriched white lighting seems to have an effect on
basic information processing among high-school students. Blue
light appears to improve processing speed and concentration of
students compared to standard lighting. Furthermore, a recent
study showed that one hour of exposure to morning bright
white light advances sleep and wake-up parameters and affects
cognitive performance and alertness [41]. These studies
suggest that a sufficiently applied light intervention could
enhance alertness, and thus performance, at work significantly.
Other recent studies showed the effects of bright light on
healthy-active persons during regular daytime working hours.
A field study by Smolders, De Kort, and Van den Berg [42]
provided support for a direct link between exposure to more
intense light and feelings of vitality during daytime and in
everyday situations. Their results showed that hourly light
exposure was a significant predictor of vitality. People who
were exposed to more light experienced higher feelings of
vitality, over and above the variance explained by person
characteristics, time of day and activity patterns. Another
laboratory study showed that even in the absence of sleep and
light-deprivation, exposure to a higher illuminance at eye level
can induce subjective alertness and vitality, increase
physiological arousal and improve performance on a sustained
attention task [44]. The same results were found by Leichfried
et al. who concluded that that early morning illumination
improves subjective alertness and mood, but had no impact
melatonin level and mental performance of individuals [43].
Short exposure to light has been found to improve thalamic,
frontal, and parietal activities, and thus affects fatigue [38],
[44]. Moreover, as short-wavelength light is significantly
effective for phase-shifting the circadian pacemaker,
suppressing melatonin, and activating the autonomic nervous
system, studies suggest that long duration exposure of bright
light is an influential potential countermeasure for fatigue,
especially during the biological night. Routine tasks such as
driving which need sustain attention are improved by exposure
to bright light [38]. It can also positively affect cognitive as
well as physical performance in healthy individuals [45]-[47].
All these studies demonstrate a direct relationship between
intense early morning daylight and alertness, vitality, and
cognitive performance. All of these are key factors affecting
work and scholastic performance of individuals. Although
these studies have not assessed the impacts of morning daylight
on students’ alertness and productivity directly, they might be
extended to students. Considering the results of these studies, it
appears to be necessary to expose students to short bright light
during the early part of the day to maintain entrainment. These
findings seem to have significant and practical implications on
the design of schools in general and classrooms in particular.
Impacts of blue light in schools could be considered as a
simple, beneficial, non-pharmacological way which enhance
students’ health, alertness, brain activity, and vitality and
perhaps academic performance. Sunlight seems to be the most
appropriate lighting source in schools as it can deliver the
adequate quantity and spectrum as well as the proper timing
and duration of light exposure [38], [39]. These findings should
have direct implications on the layout of schools as well as
façade orientations and fenestration design in schools
VII. CONCLUSIONS
Among many elements in indoor environment, light seems to
have the most impacts on human body. Various studies have
investigated the impacts of light on people from different points
of view for over a century. These studies demonstrated that
light has visual and non-visual influences on people. Among
different source of lighting, it seems that sunlight is the most
effective one, as it comprises adequate quantity and a broad
spectrum of light. In addition, it is the most important source of
vitamin D which is necessary for human bones strength and
overall health. In addition to its role as an agent for vitamin D
production in human blood, natural light can improve
subjective mood, attention, cognitive performance, physical
activity, sleep quality, and alertness in humans. All these
factors could be considered key aspects for optimal academic
and work performance.
REFERENCES
[1] L. Bellia, F. Bisegna, and G. Spada, “Lighting indoor environment: visual
and non-visual light sources with different spectral power distribution,”
Building and Environment, vol. 46, pp. 1984-1992, 2011.
[2] J.H. Heerwagen, “Green buildings, organizational success, and occupant
productivity,” Building Research and Information, vol. 28 (5), pp.
353-367, 2000.
[3] G. Vandewalle, P. Maquet, and D.J. Dijk, “Light as a modulator of
cognitive brain function,” Trends in Cognitive Sciences, vol. 13, pp.
429–438, 2009.
[4] L. Baker, A History of School Design and Its Indoor Environmental
Standards, 1900 to Today. Washington, DC: National Clearinghouse for
Educational Facilities, 2011, pp. 39-45.
[5] R. Kuller, C. Lindsten, “Health and behavior of children in classrooms
with andwithout windows. Journal of Environmental Psychology, vol. 12,
pp. 305-17, 1992.
[6] Heschong Mahone Group. Windows and Classrooms: A Study Of Student
Per-Formance And The Indoor Environment. Sacramento, CA:
California Energy Commission; 2003.
[7] IES RP-5-13. Recommended Practice for Daylighting Buildings.
Illuminating Engineering Society, 2013.
[8] Boubekri, M. Daylighting, Architecture and Health, NY: Architectural
Press, 2008.
[9] F. Sharp, D. Lindsey, J. Dols, J. Coker, “The use and environmental
impact of daylighting,” Journal of Cleaner Production, vol. 85, pp.
462-471, 2014.
[10] V.R. Garcia-Hansen, "Innovative daylighting systems for deep-plan
commercial buildings." PhD. Dissertation, Faculty of Built Environment
and Engineering, Queensland University of Technology, Brisbane, 2006.
[11] S. Altomonte, “Daylight and the Occupant, Visual and
physio-psychological well-being in built environment,” presented at 26th
Conference on Passive and Low Energy Architecture, Quebec City,
Canada, 22-24 June, 2009.
[12] W.J.M. Van [14], “Non-visual biological effect of lighting and the
practical meaning for lighting for work” Applied Ergonomics, vol. 37, pp.
461-466, 2006.
[13] W.J.M. Van Bommel, G.J. Van den Beld, “Lighting for work: a review of
visual and biological effects,” Lighting Research and Technology, vol. 36
(4), pp. 255-269, 2004.
[14] M. Boubekri, L. Cheung, K. Reid, C. Wang, &and P. Zee, “Impact of
windows and daylight exposure on overall health and sleep quality of
office workers: A case- control pilot study,” Journal of Clinical Sleep
Medicine, vol. 10(6), pp. 603-611, 2014.
[15] D. Aggio, L. Smith, A. Fisher, and M. Hamer, “Association of light
exposure on physical activity and sedentary time in young people,”
International Conference on “Health, Biological and Life Science” (HBLS-16) April 18-19, 2016 Istanbul, Turkey
156
International Journal of Environmental Research and Public Health, vol.
12, p p. 2941-2949, 2015.
[16] O. Friborg, J. Rosenvinge, R. Wynn, and M. Gradisar, “sleep timing,
phonotype, mood, and behavior at an arctic latitude (69°N). Sleep
Medicine, vol. 15, pp. 798–807, 2014.
[17] R.G. Stevens, and M.S. Rea, M. S., “Light in the built environment:
potential role of circadian disruption in endocrine disruption and breast
cancer,” Cancer causes and control, vol.12, pp. 279-287, 2011.
[18] D.H. Avery, D.N Eder, M.A. Bolte, C.J. Hellekson, D.L. Dunner, M.V.
Vitiello, and P.N. Prinz, “Dawn simulation and bright light in the
treatment of SAD: a controlled study,” Biological Psychiatry, vol. 50(3),
pp. 205–16, 2001.
[19] L. Edwards, P. A. Torcellini, and N. R. E, “A literature review of the
effectsof natural light on building occupants,” National Renewable
Energy Laboratory, 2002.
[20] G. Hoffmann, V. Gufler, A. Griesmacher, C. Bartenbach, M. Canazei, S.
Staggl, and M. Schobersberger, “Effects of Variable Lighting Intensities
and Color Temperatures on Sulphatoxymelatonin and Subjective
Moodin an Experimental Office Workplace,” Applied Ergonomics, vol.
39, pp. 719–728, 2008doi:10.1016/j.apergo.2007.11.005.
[21] C.L. Robbins, Daylighting: Design and Analysis, New York: Van
Nostrand Reinhold, 1986.
[22] L. Gelfand, E. C. Freed, Sustainable School Architecture: Design for
Elementary and Secondary School, John Wiley and Sons Inc.
[23] P. Boyce, C. Hunter, and O. Howlett, “The Benefits of Daylight through
Windows,” Lighting Research Center, Rensselaer Polytechnic Institute,
New York, 2003.
[24] H. Jusle, and A. Tenner, “Mechanisms involved in enhancing human
performance by changing the lighting in the industrial workplace,”
International Journal of Industrial Ergonomics, vol. 35, pp. 843–855,
2005.
[25] J.J. Romm and W.D. Browning, “Greening the building and the bottom
line - Increasing productivity through energy-efficient design,” Rocky
Mountain Institute, 1994.
[26] A. Borisuit, F. Linhart, J. Scartexxini, and M. Munch, “Effects of realistic
office daylighting and electric lighting conditions on visual comfort,
alertness and mood, lighting Res,” Technol., [Online], vol. 0, pp. 1-18.
Available: lrt.sagepub.com.
[27] S. Markussen, and K. Røed, “Daylight and absenteeism – Evidence from
Norway,” Economics and Human Biology, vol. 16, pp. 73–80, 2014.
1-s2.0-S1570677X14000252-main.
[28] A. Demir, “Impact of daylight on student and teacher performance,
Journal of Educational and Instrutional Studies in the World, vol. 3 (1),
pp. 1-7, 2013.
[29] Johnson, Raymond, J. Leo, M. Bernabei, “Green Building Design for
Schools: The Next Time Around,” Strategic Planning for Energy and the
Environment, vol. 26 (2), pp. 56-77, 2006.
[30] M. Anselm Dass, N. Ibrahim, N. Lukman, “Evaluation of daylighting at
public school classrooms in Ipoh, Perak,” Alam Cipta, vol. 7(1), pp.
27-34, 2014.
[31] National Research Institute (National Research Council), Green Schools:
Attributes for Health and Learning, Washington: The National
Academies Press, 2007.
[32] L. Heschong, L. Roger, S. Wright, “Daylighting impacts on human
performance in school. Journal of Illuminating Engineering Society
Summer, 101-114, 2002.
[33] A. Taylor and K. Engass, Linking Architecture and Education:
Sustainable Design For Learning Environments, China: University of
New Mexico Press, 2009.
[34] T. Kim, W. Hong, H. Kim, “Daylight evaluation for educational facilities
established in high-rise housing complexes in Daegu, South Korea,”
Building and Environment, vol. 78, pp. 37-144, 2014,
http://dx.doi.org/10.1016/j.buildenv.2014.04.026
[35] D. Aggio, L. Smith, A. Fisher, and M. Hamer, “Association of Light
Exposure on Physical Activity and Sedentary Time in Young People,”
International Journal of Environmental Research and Public Health, vol.
12, pp. 2941-2949, 2015.
[36] S.W. Lockley et al. “Short-wavelength sensitivity for the direct effects of
light on alertness, vigilance, and the waking electroencephalogram in
humans,” Sleep Physiology, vol. 29, pp. 161–168, 2006.
[37] G. Vandewalle, “Brain responses to violet, blue, and green
monochromatic light exposures in humans: prominent role of blue light
and the brainstem,” PLoS ONE, vol. 2, pp. 1239-1247, 2007.
[38] M.G. Figueiro and M.S. Rea, “Evening daylight may cause adolescents to
sleep less in spring than in winter,” Chronobiology International, vol. 27,
pp. 1242-1258, 2010a.
[39] M.G. Figueiro, M.S. Rea, “Lack of short-wavelength light during school
day delays dim light melatonin onset (DLMO) in middle school students,”
Neuroendocrinology Letters, vol. 31, pp. 92-96, 2010 b.
[40] O. Keis, H. Helbig, J. Streb, K. Hille, “Influence of blue-enriched
classroom lighting on students’ cognitive performance,” Trends in
Neuroscience and Education, vol. 3, pp. 86-92, 2014.
[41] R.W. Corbett, B. Middleton, J. Arendt, “An hour of bright white light in
the early morning improves performance and advances sleep and
circadian phase during the Antarctic winter,” Neurocience Letters, vol.
525(2), pp. 146-151, 2012.
[42] K.C. Smolders, Y.A. De Kort, A.D. Tenner and F.G. Kaiser, “Need for
recovery in offices: Behavior-based assessment,” Journal of
Environmental Psychology, vol. 32, pp. 126-134, 2012.
http://dx.doi.org/10.1016/j.jenvp.2011.12.003.
[43] V. Leichtfred et al. “Intense illumination in the morning hours improved
mood and alertness but not mental performance,” Applied Ergonomics,
vol. 46, pp. 54-59, 2015.
[44] G. Vandewall, et al., “Daytime light exposure dynamically enhances
brain responses,” Curr Biol, vol. 16(16), pp.1616–21, 2006.
[45] T. Kantermann, S. Forstner, M. Halle, L. Schlangen, T. Roenneberg, A.
Schmidt- Trucksass, “The stimulating effect of bright light on physical
performance depends on internal time,” PLoS ONE, vol. 7 (7), pp.
406-55, 2012.
[46] A.B. Dollins, H.J. Lynch, R.J. Wurtman, M.H. Deng, K.U. Kischka,, R.E.
Gleason, H.R. Lieberman, “Effect of pharmacological daytime doses of
melatonin on human mood and performance,” Psychopharmacology
(Berl.), vol. 112 (4), pp. 490-496, 1993.
[47] F.A. Fraschini, D. Cesarani, D. Alpini, D. Esposti, B.M. Stankov,
Melatonin influences human balance,” Biol. Signals Recept. Vol. 8 (1-2),
pp. 111-119, 1999.
Studied at University of Illinois at Urbana-Champaign,
Nastaran Shishegar is an architect (M. Arch, MSc
Engineering, BSc) lighting specialist, and sustainability
expert who specializes in sustainable design and energy
efficient buildings. She has both researched and worked
on sustainable architecture and green buildings to
encourage industries and societies to save energy.
Nastaran’s research focuses on the sustainable
architecture, building energy performance, and
specifically, the impacts of daylighting and indoor environmental quality on
occupants’ health, satisfaction, and productivity. Her mission is to present a
greener world which is healthier and happier.
Dr. Mohamed Boubekri is a professor of architecture at
the University of Illinois at Urbana- Champaign. He is
a William Wayne Caudill Research Fellow, and twice a
Fulbright Fellow. Professor Boubekri’s research
focuses on sustainable architecture and the intersection
of the built environment and human health and
well-being. He has published more than 70 journal
articles and conferences papers. His first book,
published in 2008 with the Architectural
Press-Elsevier, explores the impact of daylighting of buildings on people’s
health and overall well-being. His second book published in September 2014
with Birkhäuser-Verlag explores the subject of daylighting and the health and
well-being of building occupants as well as design strategies and best practice
solutions.