Technology · June 23, 2022

Cell phones and screens keep your child awake

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New research says bedroom gadgets are causing kids to lose sleep time and quality

Even kids and teens who don’t stay up late online are losing sleep


Today’s teachers are often confronted with classrooms full of yawning students who stayed up late taking selfies or playing online games.

For children and teens, nocturnal use of cellphones, tablets and computers is associated with loss of sleep time and sleep quality, new research finds. Even children who don’t use their phones or other technology that clutters their bedrooms at night are losing their eyesight and becoming prone to daytime sleepiness, according to analysis published today in JAMA Pediatrics.

The analysis revealed “a consistent pattern of impact across a variety of countries and settings,” said Dr. Ben Carter, lead author and Lecturer in Biostatistics at King’s College London.

Carter and his colleagues scoured the medical literature to identify hundreds of applicable studies conducted between January 1, 2011 and June 15, 2015. They selected 20 research reports totaling 125,198 children, evenly split by sex, with a mean age of 14½ years. After extracting relevant data, Carter and his co-authors performed their own meta-analysis.

Few parents will be surprised by the results: the team found a “strong and consistent association” between bedtime media device use and insufficient sleep amount, poor sleep quality, and excessive daytime sleepiness.

Surprisingly, however, Carter and his team found that children who didn’t use their devices in their bedrooms were still getting interrupted sleep and likely suffered from the same problems. The lights and sounds emitted by the technology, as well as the content itself, can be too stimulating.

Although Carter admits that one weakness of the analysis was “how the data in the primary studies were collected: parent and child self-reports,” many of us will likely recognize our own family’s habits reflected in the statistics.

A major 2013 US survey by the National Sleep Foundation (PDF) found that 72% of children and 89% of teens have at least one device in their sleep environment. Most of this technology is used before bed, the same report found.

According to Carter and his co-authors, this ubiquitous technology negatively affects children’s sleep by delaying their sleep time when they finish watching a movie or playing another game.

The light emitted by these devices can also affect the circadian rhythm, the body clock that controls biological processes including body temperature and hormone release, the researchers explain. A specific hormone, melatonin, causes fatigue and contributes to the timing of our sleep-wake cycles. Electronic light can delay the release of melatonin, disrupting this cycle and making it difficult to fall asleep.

Carter and his co-authors also point out that online content can be psychologically stimulating, keeping children and teens awake well past the hour when they turn off their devices and try to sleep.

“Sleep is vital for children,” said Dr. Sujay Kansagra, director of the sleep medicine program in pediatric neurology at Duke University Medical Center, who was not involved in the new analysis. “We know that sleep plays a critical role in brain development, memory, self-regulation, attention, immune function, cardiovascular health and more.”

Kansagra, author of “My Child Won’t Sleep,” noted that the time of greatest brain development is in our first three years of life, which is when we need and get the most sleep. “It’s hard to believe that this would be a coincidence.”

Kansagra said it’s possible that parents underreported children using devices at night, but it’s more likely that the technology is simply disrupting sleep hygiene. “For example, children who are allowed to keep devices in their room may be more likely to avoid a good sleep routine that we know is helpful for sleep,” he said.

dr Neil Kline, a representative of the American Sleep Association, agrees that sleep plays an essential role in a child’s healthy development, although “we don’t know all the science behind it. There’s even some research showing a link between ADHD and some sleep disorders.

The results of the new study come as no surprise in many respects. “Especially in the teenage years, sleep hygiene is significantly influenced by technology,” says Kline, who bases his opinion not only on research, but on “personal experiences and also the anecdotes of many other sleep experts”.

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  • Sleep hygiene – tips to help ensure a good, consistent, and adequate night’s sleep – includes a quiet room. “And that would mean removing objects that disrupt sleep, including electronics, televisions, and even pets if they disrupt sleep,” Kline said.

    Another key tip comes from the National Sleep Foundation, which recommends at least 30 minutes of “gadget-free transition time” before bed. Switch off for better sleep.

    Other recommendations for good sleep hygiene include not moving (physically or mentally) too close to bedtime; establishing a regular sleep schedule; Limiting exposure to light before sleep; Avoiding stimulants such as alcohol, caffeine, and nicotine in the hours before bed; and creates a dark, comfortable and peaceful sleeping environment.