Screens and Sleep

shutterstock_147721862-smallTechnology and Our Healthy Sleep

Research shows that light from screens and radiation from wireless can impact our sleep. The quality of our sleep profoundly impacts learning and memory and is essential for retaining new information. A sleep-deprived child cannot focus their attention as well as a child who had a good night’s sleep. Early research showed that teenagers who use their phones more had more trouble falling asleep and staying asleep and were more tired and stressed than those who sparingly used their phones. New research confirms these associations and strongly suggests that simple basic changes to our tech use and nighttime routines can result in a better night’s sleep.

Furthermore, research shows that sleep is a time when the brain cleans out toxins accumulated during the daytime. Ensuring a healthy sleep is one of the most powerful steps we can take to prevent illness and protect our family’s health and wellbeing.

Wireless radiation impacts sleep in several ways.

Research has shown that exposure to wireless radiation results in delayed entrance into deep non-REM sleep and decreases time spent in certain sleep stages.

  • The blue light from screens has been shown to disrupt sleep cycles. The American Medical Association issued a policy to develop and implement healthier technologies recognizing “that exposure to excessive light at night, including extended use of various electronic media, can disrupt sleep or exacerbate sleep disorders, especially in children and adolescents.”
  • Research on wireless radiation has shown that it inhibits the production of a hormone called melatonin (see the scientific references at the bottom of this webpage). Melatonin is secreted in the pineal gland in the brain. One of its primary functions is to regulate our sleep cycle. When inadequate amounts of melatonin are produced, our sleep cycle is compromised.

Why is sleep important?
Studies have shown a relationship between sleep problems and child psychosocial problems like attention, hyperactivity, oppositional and aggressive behaviour, mood problems, and anxiety. New research is also showing that sleep characteristics are important factors in the development of neurological conditions such as Alzheimer’s disease. Over a long period of time, the consequences of sleep deprivation can be severe.

How are wireless devices impacting sleep?
People, especially teens, stay up late texting friends or communicating on Facebook, Instagram, Twitter, and other social media sites. Unlike a phone call to one person, these conversations can go on for hours between dozens of people. Many teens express that they find it a challenge to put their phones down because they might “miss something”.

What devices emit blue light?
Smartphones, tablets, computers, and energy-saving fluorescent bulbs emit blue light. We hold the electronic screens of phones very close to our faces, increasing the intensity and effects of the blue light on our brains. Screens close to the face are much worse blue light exposure than a television that is 10 feet away.

How does the blue light impact sleep?
Nighttime exposure to artificial light disrupts the human body’s circadian rhythm, changing the biological clock that controls our sleep-wake cycle. Our eyes contain light-sensitive cells that detect light. These cells are separate from those we use for vision and contain a photopigment called melanopsin that is particularly sensitive to blue light. Scientists think this light-detecting mechanism, which regulates our sense of night and day and time of year, evolved before the ability to see.

Blue light is prominent in daylight and it makes us more alert. Blue light also suppresses melatonin, which is a hormone that helps regulate sleep. Exposure to blue light at night shifts our body’s clock and results in a more alert brain that thinks it is daytime.


What does research on sleep, screens, and light show?
Studies have shown that blue wavelength light suppresses melatonin levels more vigorously than other light wavelengths. While daytime exposure can increase our alertness, nighttime exposure damages our circadian rhythms.

  • A 2014 study published  in PNAS shows that reading a backlit device before bed makes your sleep significantly worse than reading a paper book under dim light. According to the study, people who used an iPad at night produced 55% less melatonin, took an extra 10 minutes to fall asleep, and had less REM sleep during the night. The next morning, the iPad readers felt sleepier, and it took them “hours longer” to feel alert, whereas the book readers quickly felt more alert immediately upon waking. Additionally, when it was time for bed the next night, the iPad readers’ circadian clocks were delayed by more than 90 minutes and their bodies began to feel tired an hour and a half later than normal.
  • In May 2011, Swiss researchers at the University of Basel reported that subjects who spent time at night in front of an LED computer screen, rather than a screen emitting a variety of colors but little blue light, experienced “a significant suppression of the evening rise in endogenous melatonin and … sleepiness.”
  • A study of  adults who wore either blue-light blocking or ultraviolet-light blocking glasses for 3 hours before sleep found that both sleep quality and mood improved among those in the group who wore blue-light blocking glasses, compared to the ultraviolet-light blocking group.

ADDITIONAL REFERENCES AND NEWS ARTICLES

Mobile phone radiation wrecks your sleep, HEALTH NEWS

Sleep Drives Metabolite Clearance from the Adult Brain, Science 18 October 2013

Harvard Health Letter: Blue light has a dark side

Study Shows Small Screens in Children’s Bedrooms Can Harm Sleep: American Academy of Pediatrics

Bright Screens Could Delay Bedtime: Using a tablet or computer in the late evening disrupts the body’s melatonin production, Scientific American


SCIENTIFIC REFERENCES ON WIRELESS AND SLEEP

A double-blind, randomized, sham-controlled cross-over study on the possible effects of electromagnetic fields emitted by pulsed Global System for Mobile Communications (GSM) 900 and Wideband Code-Division Multiple Access (WCDMA)/Universal Mobile Telecommunications System (WCDMA/UMTS) devices on sleep were analyzed.

RF-EMF effects are observed in 90% of the individuals and that all sleep variables are affected in at least four subjects.

  • The results underline that sleep of individuals can be affected differently. The observations found here may indicate an underlying thermal mechanism of RF-EMF on human REM sleep.

Circadian rhythmicity of antioxidant markers in rats exposed to 1.8 ghz radiofrequency fields.
Cao H et al., Circadian rhythmicity of antioxidant markers in rats exposed to 1.8 ghz radiofrequency fields. International Journal of Environmental Research and Public Health. 2015 Feb 12;12(2):2071-87.

  • The overall results indicate that there may be adverse effects of radiofrequency field exposure on antioxidant function, in terms of both the daily antioxidative levels, as well as the circadian rhythmicity.

Stimulation of the brain with radiofrequency electromagnetic field pulses affects sleep-dependent performance improvement.
Lustenberger C et al., Stimulation of the brain with radiofrequency electromagnetic field pulses affects sleep-dependent performance improvement. Brain Stimul. 2013 Sep;6(5):805-11. doi: 10.1016/j.brs.2013.01.017. Epub 2013 Feb 24.

  • “Under exposure, sleep-dependent performance improvement in the motor task was reduced compared to the sham exposure condition. The study showed that a radiofrequency electromagnetic field exposure may directly affect ongoing brain activity during sleep, and as a consequence alter sleep-dependent performance improvement.”

The Effects of 884 MHz GSM Wireless Communication Signals on Self-reported Symptom and Sleep (EEG)- An Experimental Provocation Study PIERS Online Vol. 3 No. 7 2007 pp: 1148-1150
Bengt et al., The Effects of 884 MHz GSM Wireless Communication Signals on Self-reported Symptom and Sleep (EEG)- An Experimental Provocation Study PIERS Online Vol. 3 No. 7 2007 pp: 1148-1150

  • A prolonged latency to reach the first cycle of deep sleep (stage 3). The amount of stage 4 sleep was also decreased in exposed subjects. Subjects reported more headaches during exposures vs. sham exposure.

Sleep EEG alterations: effects of different pulse-modulated radio frequency electromagnetic fields.
Schmid et al., Sleep EEG alterations: effects of different pulse-modulated radio frequency electromagnetic fields. Sleep Res. 2012 Feb;21(1):50-8. Apr 12.

  • “Consistent with previous findings, our results provide further evidence that pulse-modulated RF EMF alter brain physiology.”

Effects of Pulsed High-Frequency Electromagnetic Fields on Human Sleep
Mann and J. Röschke, Effects of Pulsed High-Frequency Electromagnetic Fields on Human Sleep, Neuropsychobiology 33:41-47, 1996

  • Shortening of sleep onset latency and a REM (Rapid Eye Movement) suppressive effect with reduction of duration and percentage of REM sleep. “The effects observed possibly could be associated with alterations of memory and learning functions.”

Pulsed radio-frequency electromagnetic fields: dose-dependent effects on sleep, the sleep EEG and cognitive performance.
Regel Set al. Pulsed radio-frequency electromagnetic fields: dose-dependent effects on sleep, the sleep EEG and cognitive performance. J Sleep Res. 2007 Sep;16(3):253-8.

  • Showed a dose-response relationship between EMF field intensity and its effects on brain physiology as demonstrated by changes in the sleep EEG and in cognitive performance.

REFERENCES ON MEDIA USE AND SLEEP

Sleep Duration, Restfulness, and Screens in the Sleep Environment
Falbe et al, Sleep Duration, Restfulness, and Screens in the Sleep Environment, Pediatrics, 2014-2306; published ahead of print January 5, 2015

  • “Sleeping near a small screen, sleeping with a TV in the room, and more screen time were associated with shorter sleep durations. Presence of a small screen, but not a TV, in the sleep environment and screen time were associated with perceived insufficient rest or sleep. These findings caution against unrestricted screen access in children’s bedrooms.”

Association between electronic media use and sleep habits: an eight-day follow-up study
Kubiszewski, Fontaine, Rusch and Hazouard, Association between electronic media use and sleep habits: an eight-day follow-up study, International Journal of Adolescence and Youth, Volume 19, Issue 3, 2014

  • In practice, youngsters have a multiple rather than a single use of electronic media (EM) every day. This study examined the association between electronic stimulation throughout the day, the final evening activity every day of the week, EM availability in the bedroom and sleep problems in 332 middle-school children. An evening screen time of one hour or more is associated with a higher risk of sleep problems, particularly going to bed late and difficulty waking up. Possession and pattern of EM use by adolescents are associated with impaired sleep quality and late bedtimes, indicating the need to control adolescents’ screen time.

The Association Between Use of Electronic Media in Bed Before Going to Sleep and Insomnia Symptoms, Daytime Sleepiness, Morningness, and Chronotype, Behavioral Sleep Medicine
Ingrid Nesdal Fossum, Linn Tinnesand Nordnes, Sunniva Straume Storemark, Bjørn Bjorvatn, Ståle Pallesen, The Association Between Use of Electronic Media in Bed Before Going to Sleep and Insomnia Symptoms, Daytime Sleepiness, Morningness, and Chronotype, Behavioral Sleep Medicine, Vol. 12, Iss. 5, 2014

  • This study investigated whether the use of a television, computer, gaming console, tablet, mobile phone, or audio player in bed before going to sleep was associated with insomnia, daytime sleepiness, morningness, or chronotype. Mean time of media use per night was 46.6 minutes. The results showed that computer usage for playing/surfing/reading was positively associated with insomnia, and negatively associated with morningness. Mobile phone usage for playing/surfing/texting was positively associated with insomnia and chronotype, and negatively associated with morningness.

Media Use and Child Sleep: The Impact of Content, Timing, and Environment.
Garrison MM, Liekweg K, and Christakis DA. Media Use and Child Sleep: The Impact of Content, Timing, and Environment. Pediatrics; originally published online June 27, 2011; DOI: 10.1542/peds.2010-3304

  • Violent content and evening media use were associated with increased sleep problems. Children with a bedroom television consumed more media and were more likely to have a sleep problem. Each additional hour of evening media use was associated with a significant increase in the sleep problem score and there  was a trend toward greater impact of daytime violent use in the context of a bedroom television.

Electronic media use and sleep in school-aged children and adolescents: A review.
Cain N, Gradisar M. Electronic media use and sleep in school-aged children and adolescents: A review. Sleep Medicine. 2010;11(8):735-742.

  • The  study identified 36 papers that have investigated the relationship between sleep and electronic media in school-aged children and adolescents, including television viewing, use of computers, electronic gaming, and/or the internet, mobile telephones, and music. Delayed bedtime and shorter total sleep time have been found to be most consistently related to media use.

Television Viewing, Bedroom Television, and Sleep Duration From Infancy to Mid-Childhood
Cespedes EM1, Gillman MW, Kleinman K, Rifas-Shiman SL, Redline S, Taveras EM, Television Viewing, Bedroom Television, and Sleep Duration From Infancy to Mid-Childhood. Pediatrics. 2014 Apr 14.

  • More TV viewing, and, among racial/ethnic minority children, the presence of a bedroom TV, were associated with shorter sleep from infancy to mid-childhood.

The health indicators associated with screen-based sedentary behavior among adolescent girls: a systematic review.
Costigan SA, Barnett L, Plotnikoff RC, Lubans DR. The health indicators associated with screen-based sedentary behavior among adolescent girls: a systematic review. Journal of Adolescent Health. 2013 Apr;52(4):382-92. doi: 10.1016/j.jadohealth.2012.07.018. Epub 2012 Sep 25.

  • A positive association was observed between screen-time and sleep problems, musculoskeletal pain and depression. Negative associations were identified between screen time and physical activity/fitness, screen time and psychological well-being, and screen time and social support. Strong evidence for a positive association between screen-based sedentary behavior and weight status was found.

Screen media usage, sleep time and academic performance in adolescents: clustering a self-organizing maps analysis.
Peiró-Velert, Valencia-Peris, González L, García-Massó, Serra-Añó P, Devís-Devís Screen media usage, sleep time and academic performance in adolescents: clustering a self-organizing maps analysis. PLoS One. 2014 Jun 18;9(6):e99478. doi:10.1371/journal.pone.0099478. eCollection 2014.

  • Academic performance was directly related to sleep time and socioeconomic status, but inversely related to overall sedentary screen media usage. “Findings may contribute to establishing recommendations about the timing and duration of screen media usage in adolescents and appropriate sleep time needed to successfully meet the demands of school academics and to improve interventions targeting to affect behavioral change.”

Effects of Pre-Sleep Media Use on Sleep/Wake Patterns and Daytime Functioning Among Adolescents: The Moderating Role of Parental Control
Delphine Pieters, Elke De Valck, Marie Vandekerckhove, Sandra Pirrera, Johan Wuyts, Vasileios Exadaktylos, Bart Haex, Nina Michiels, Johan Verbraecken, Raymond Cluydts, Effects of Pre-Sleep Media Use on Sleep/Wake Patterns and Daytime Functioning Among Adolescents: The Moderating Role of Parental Control, Behavioral Sleep Medicine, Vol. 12, Iss. 6, 2014

  • The aim of this cross-sectional study was to investigate the influence of media use in the hour before bedtime on sleep/wake patterns and daytime functioning among adolescents and to examine the moderating role of parental control. A total of 1,926 Belgian students, 55% girls and 45% boys, with a mean age of 16.9 ± 1.5 years, completed a modified version of the School Sleep Habits Survey. Correlational analyses showed that media use, except television viewing, was associated with later bedtimes and longer sleep latencies. Cell phone and computer usage was negatively associated with daytime functioning. On schooldays, parental control had a moderating effect on the relationship between bedtime and computer use.