Study: Blue light may affect the sleep habits of students

13 Dec

The goal of this society should be to raise healthy and happy children who will grow into concerned and involved adults who care about their fellow citizens and environment. In order to accomplish this goal, all children must receive a good basic education and in order to achieve that goal, children must arrive at school, ready to learn. One of the mantras of this blog is there should not be a one size fits all approach to education and that there should be a variety of options to achieve the goal of a good basic education for all children.

The University of Illinois Extension has some good advice for helping children with study habits. In Study Habits and Homework he University of Illinois recommends:

Parents can certainly play a major role in providing the encouragement, environment, and materials necessary for successful studying to take place.
Some general things adults can do, include:
Establish a routine for meals, bedtime and study/homework
Provide books, supplies, and a special place for studying
Encourage the child to “ready” himself for studying (refocus attention and relax)
Offer to study with the child periodically (call out spelling words or do flash cards)

Some folks claim they need as few as four hours of sleep. For most folks, that is not healthy and it definitely isn’t healthy for children.

Sarah D. Sparks reported in the Education Week article, ‘Blue Light’ May Impair Students’ Sleep, Studies Say:

Schools may soon face an unintended consequence of more flexible technology and more energy-efficient buildings: sleepier students.
That’s because evidence is mounting that use of artificial light from energy-efficient lamps and computer and mobile-electronics screens later and later in the day can lead to significant sleep problems for adults and, particularly, children.
While lights and electronic devices that mimic daylight can improve students’ attention and alertness if used during normal daytime hours, Dr. Charles A. Czeisler, a professor of sleep medicine at Harvard Medical School, has found exposure in the late afternoon and evening can disrupt sleep cycles as much as six to eight hours—the same amount of “jet lag” caused by a flight from New York City to Honolulu.
“Technology has disconnected us from the natural 24-hour day,” Dr. Czeisler said in a keynote lecture at the Society for Neuroscience meeting held here last month.
That could lead to headaches for school districts across the country that are rolling out take-home electronic devices in an effort to boost student achievement.
Two connected systems determine how people of all ages sleep. The first is pretty straightforward: The longer it’s been since you’ve slept, the sleepier you get. The second system, called the circadian cycle, is more complex and can easily come into conflict with a person’s basic sleep drive.
Human brains regulate circadian sleep through exposure to short-wavelength “blue” light, which makes up the bulk of bright daylight. Short-wavelength light increases cortisol in the brain, which regulates alertness. As blue light during the day fades to the longer-wavelength, redder light of dusk, the brain’s timekeeper, the hypothalamus, suppresses cortisol and releases the sleep-promoting chemical melatonin.
One study released this month in the Journal of Cognitive Neuroscience showed that even those who are functionally blind become more alert and have increased brain activity in response to blue light, suggesting it can have effects even when it can’t be seen.
‘Biologically Potent’
In several studies, Dr. Czeisler has found that light-emitting diodes, or LEDS, which contain a large proportion of blue light, are more “biologically potent”—twice as effective at resetting the brain’s circadian clock as incandescent light. College students exposed to even brief periods of blue light late in the day showed delayed release in melatonin and up to a two-hour delay in sleep time.
Losing Shut-Eye
As students move through school, the gap between the amount of sleep they get on school nights and the amount they get on weekend nights tends to grow.
Blue light is becoming ubiquitous in any device that uses LEDS—including tablet and laptop computers, energy-efficient lamps, and some televisions. The Arlington, Va.-based National Sleep Foundation found this year that more than half of Americans use a computer, laptop, or tablet device in the hour before sleep every night or nearly every night. More than seven in 10 also have televisions in their bedrooms.
In real life, that can create an unhealthy cycle: Students exposed to blue light late in the day feel less sleepy and continue to do homework or play online until very late, exposing themselves to more light and making it harder to feel sleepy, even as their need for sleep grows. In the past 50 years, Americans’ average sleep time has dropped from 8.5 hours a day to only 6.9 hours, Harvard’s Dr. Czeisler said. An analysis of nearly 700,000 school-age children in 20 countries found that they slept on average 75 minutes less a night in 2008 than in 1905, with American children’s sleep shrinking more rapidly than for those in most other countries…..


December 2013, Vol. 25, No. 12, Pages 2072-2085
Posted Online October 30, 2013.
© 2013 Massachusetts Institute of Technology
Blue Light Stimulates Cognitive Brain Activity in Visually Blind Individuals
Gilles Vandewalle1,2*,**, Olivier Collignon3,4*,†, Joseph T. Hull5,6, Véronique Daneault1,2, Geneviève Albouy1, Franco Lepore3, Christophe Phillips7, Julien Doyon1, Charles A. Czeisler5,6, Marie Dumont2, Steven W. Lockley5,6††, and Julie Carrier1,2††
1University of Montréal Geriatric Institute, Québec, Canada
2Hôpital du Sacré-Cœur de Montréal, Québec, Canada
3Université de Montréal, Québec, Canada
4Centre de Recherches CHU Sainte-Justine, Montréal, Québec, Canada
5Brigham and Women’s Hospital, Boston, MA
6Harvard Medical School, Boston, MA
7University of Liège, Belgium
*These authors contributed equally to this work.
**Present address: Cyclotron Research Centre, University of Liège, Belgium.
†Present address: Centre for Mind/Brain Science, University of Trento, Italy.
††These authors are joint senior authors on this work.
Light regulates multiple non-image-forming (or nonvisual) circadian, neuroendocrine, and neurobehavioral functions, via outputs from intrinsically photosensitive retinal ganglion cells (ipRGCs). Exposure to light directly enhances alertness and performance, so light is an important regulator of wakefulness and cognition. The roles of rods, cones, and ipRGCs in the impact of light on cognitive brain functions remain unclear, however. A small percentage of blind individuals retain non-image-forming photoreception and offer a unique opportunity to investigate light impacts in the absence of conscious vision, presumably through ipRGCs. Here, we show that three such patients were able to choose nonrandomly about the presence of light despite their complete lack of sight. Furthermore, 2 sec of blue light modified EEG activity when administered simultaneously to auditory stimulations. fMRI further showed that, during an auditory working memory task, less than a minute of blue light triggered the recruitment of supplemental prefrontal and thalamic brain regions involved in alertness and cognition regulation as well as key areas of the default mode network. These results, which have to be considered as a proof of concept, show that non-image-forming photoreception triggers some awareness for light and can have a more rapid impact on human cognition than previously understood, if brain processing is actively engaged. Furthermore, light stimulates higher cognitive brain activity, independently of vision, and engages supplemental brain areas to perform an ongoing cognitive process. To our knowledge, our results constitute the first indication that ipRGC signaling may rapidly affect fundamental cerebral organization, so that it could potentially participate to the regulation of numerous aspects of human brain function.
Cited by
Vivien Bromundt, Sylvia Frey, Jonas Odermatt, Christian Cajochen. (2013) Extraocular light via the ear canal does not acutely affect human circadian physiology, alertness and psychomotor vigilance performance. Chronobiology International1-6
Online publication date: 13-Nov-2013.

Education is a partnership between the student, parent(s) or guardian(s), teachers(s), and school. The students must arrive at school ready to learn and that includes being rested. Parent(s) and guardian(s) must ensure their child is properly nourished and rested as well as providing a home environment which is conducive to learning. Teachers must have strong subject matter knowledge and strong pedagogic skills. Schools must enforce discipline and provide safe places to learn. For more information on preparing your child for high school, see the U.S. Department of Education’s Tools for Success


National Sleep Foundation’s Teens and Sleep

Teen Health’s Common Sleep Problems

CBS Morning News’ Sleep Deprived Kids and Their Disturbing Thoughts

Psychology Today’s Sleepless in America

National Association of State Board’s of Education Fit, Healthy and Ready to Learn

U.S. Department of Education’s Tools for Success


Another study: Sleep problems can lead to behavior problems in children

Stony Brook Medicine study: Teens need sleep to function properly and make healthy food choices

University of Massachusetts Amherst study: Preschoolers need naps Does school start too early?

Where information leads to Hope. © Dr.

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