How Electronic Devices Affect Sleep

In a report by the National Sleep Foundation, 89% of adults and 75% of children keep a mobile device in their bedroom. The same report noted that 95% of people use their mobile devices an hour before bedtime. Suffice it to say, most of us are addicted to technology and this addiction may inevitably lead to sleepless nights.

It’s no surprise that electronic devices – including smartphones, tablets, PC, and TV – can disrupt sleep but what’s the science behind it? Scientists agree that the increasing amount of time spent on the screen can decrease the quality of sleep, particularly in children.

Mental Alertness and Electronic Devices

In an article by, experts say that brain activity is stimulated while using a mobile device, which inevitably leads to delayed sleep. The brain responds to the blue screen by tensing up the muscles, a particularly important email or an action-packed video game session could trigger the body’s fight or flight response. When the body’s fight or flight response is triggered, the system is flooded with cortisol, a stress hormone that enhances mental alertness. This inevitably leads to sleep deprivation.

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Unfortunately, mobile devices have the ability to engage the brain for a long time. Combine that with excessive light exposure and sleeping time is reduced. A study by Michigan University scientists found that managers and employees who use their mobile devices before going to bed experience shorter sleep time along with daytime sleepiness, reduced energy levels, and fatigue. And the effects of smartphones are more significant compared to laptop computers and TV.

Blue Light and Melatonin Suppression

While there is a strong evidence that links sleep deprivation to mobile device-induced brain activity, some scientists also believe that ambient light is making a significant contribution to lack of sleep. The blue light emitted by most mobile devices is upsetting the body’s internal clock.

The fact is, the human body depends on natural daylight and darkness to trigger wakefulness and sleepiness, respectively. Being exposed to blue light – which is close to natural light – tends to disrupt the body’s internal clock, triggering the brain to remain active when it should be releasing sleep hormones.

In a study published in PNAS, scientists found that the melatonin level of the participants was reduced to 50% after being exposed to electronic devices. Melatonin is the hormone that triggers sleep. The study involved 12 volunteers who were exposed to different conditions before going to bed for 2 weeks.

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The first half of the participants were asked to read for 4 hours before bedtime using an e-reader while the other half were made to read paper books. On the second week, the first group that read before bedtime using electrical devices were made to read paper books while the second group switched to e-readers.

Scientists measured the level of melatonin on the participants’ systems and found that those who read with electrical devices experienced a significant drop in sleep hormone compared to participants who read paperback books. In addition, participants who read from e-readers took 10 minutes longer to fall asleep. On top of that, volunteers that were exposed to electronic devices experienced less deep sleep at night and most of them felt that they are not as alert the morning after.

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Electronic Devices and Insomnia

Regular mobile device usage before bedtime may also cause sleep disorders. According to a study published in the Behavioral Sleep Medicine, computer and mobile phone use are linked to insomnia symptoms. This, after monitoring 532 students who used mobile devices and computers before going to bed.

According to the report, students who spent most of their waking hours at night playing or surfing the internet showed signs of insomnia including daytime sleepiness due to upset circadian rhythms. Computer usage, in particular, was positively associated with insomnia and negatively associated with morningness.

Sleep deprivation and Texting

Sleep deprivation caused by unregulated mobile device use before bedtime affects teens so profoundly, they’re not just losing sleep, their grades are slipping too! After monitoring the texting behavior and academic performance of participating teens, a group of scientists found that those who texted more than 30 minutes after lights have gone out have the worst grades. They are also sleepier the morning after compared to students who texted less than 30 minutes.

The same study noted that students who stopped texting as soon as the lights are out-performed better at school. Researchers believe that the screen light may be responsible for text-addicted teens and the darkness amplified its effects on sleep.

How to Power Down Before Bedtime

Suffice it to say, if you’re serious about getting a deep, restful slumber night after night, you need to develop a sleep routine and power down at least an hour before bedtime. Below are tips to help you sleep better at night:

Technology-Free Time

We’re all addicted to technology but leave a little room for quiet time at night. Maintaining a technology-free time in the bedroom will help the brain transition from wakefulness to sleepiness. If you cannot spend at least an hour of mobile phone free time in the bed, cut your quiet time to at least 15 minutes.

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Keep Work-Related Tasks Off Limits

Ever woke up in a middle of the night after receiving an important email from work? Most people tend to respond to work-related emails even outside of working hours. If you want to enjoy a restful night’s sleep, do not check your email in the middle of the night. If you cannot help yourself, keep your electric outlets capped so you cannot recharge your phone to check your email.

No TV Before Bedtime

This goes for adults and children alike, no TV before bedtime. Most people tend to watch TV until they fall asleep and this leaves them exposed to blue light, causing low quality sleep. Instead of watching TV before bedtime, read a book, ideally one that’s not emotionally-charged so you don’t end up staying late finishing it!