Sleep and screen time in children

Studies have been demonstrating that some children are getting too little sleep, and that technology is driving some of the sleep deprivation. Studies have also shown that TV in a child's bedroom has been linked to less sleep. And interactive media devices like smart phones and video games may be more disruptive to sleep. This is in contract to TV viewing, which is a passive activity. Also, interactive devices are held very close to the face, meaning that light from the screens on these devices is more likely to interrupt melatonin secretion at night, which may further disrupt sleep. Finally, these interactive devices can disrupt sleep by text messages, which is not a problem with TV viewing.

This study was a cross-sectional survey of about 2000 4th and 7th graders in Massachusettes. They asked children about their TV viewing, small screen use (like cell phone, Ipad, etc), and various sleep parameters. Results showed that 54% of kids slept near a small screen and 75% slept with a TV in the room. Not surprisingly, a higher proportion of seventh graders slept near a small screen than 4th graders.

Children who slept near a small screen reported 21 fewer minutes of sleep per weekday when compared to those who did not sleep near a small screen. This effects was independent of having a TV in the room. Children who slept in a room with a TV reported sleeping 18 fewer minutes during the weekday than those without a TV in their room. This was independent of sleeping near a small screen. The results showed that the association between the screens and sleep duration resulted from a later bedtime. Sleeping near a small screen, but not a TV in the room, was associated with a 1.39 times the prevalence of perceived insufficient sleep or rest, even after adjusting for sleep duration. Not surprisingly, longer time watching TV or playing video games was associated with shorter weekday sleep duration, again accounted for by later bedtimes. And each hour spent watching TV or playing video games was associated with a higher prevalence of perceived insufficient sleep or rest. Interestingly, physical activity reduced the association between video games and perceived insufficient rest or sleep.

The study authors concluded that the small screens affect sleep quality more than TV viewing because of the stimulating content, calls, and audible text messaging while sleeping. They also mentioned that other mechanisms may contribute. For example, consuming caffeinated beverages near bedtime, evening exposure to bright light, and increased cognitive / emotional / physiologic arousal after playing video games, interacting on social media, or watching exciting / frightening TV content.

Sleep and technology

This article discusses the findings from the National Sleep Foundation's Sleep in America Poll from 2011. Some of the questions involved sleep quality and use of technology in the hour leading up to trying to sleep. The results showed that using stimulating technology that was interactive, like video games, cell phones, and computers was more disruptive to sleep than passive technology like watching TV or listening to music. The authors speculate that using stimulating technology may prevent the natural withdrawal of the sympathetic nervous system activity that is needed for sleep onset.

The implications of this research are intriguing. The results challenge, at least in part, that using passive technology in the bed can disrupt sleep. What seems to be most disruptive to sleep is stimulating technology. These findings could be extrapolated to other stimulating activities performed in the hour before bedtime, whether technology is involved or not. So perhaps the rule that the bed should be used for sleep only needs to be modified - it's possible that passive activity is not necessarily going to disrupt sleep. This goes along with my clinical experience in treating patients with chronic insomnia. Some of them have been going to sleep with the TV on in their bedroom since middle or high school. Yet their insomnia does not start for several years later, often in their late 20's. In these individuals, watching TV in the bedroom may not negatively impacting sleep quality as once thought.

Electronic devices, sleep duration, and childhood obesity

This article discusses research about pediatric obesity, sleep duration, and electronic devices in the bedroom. Not surprisingly, the more electronic devices (cell phone, TV, video games) were in the bedroom, the more likely the kid would be obese. Also, for each additional hour of sleep, obesity risk was reduced.

It's not clear from the article what contributes to what. I am convinced that screen time affects kids and adult sleep. Getting these devices out of the bedroom can improve sleep quality and duration. I am not convinced that just getting more sleep will reduce childhood obesity. More sleep may improve mood and academic performance, both of which can be negatively affected by insufficient sleep.

Video game playing and sleep fragmentation

Playing video games before bed can disrupt sleep and often reduce available sleep time, leaving kids and many adults sleep deprived. This article is about a study showing that the longer a child played video games before bed, the more broken up their sleep. It could be the light from the screen suppressing melatonin secretion and/or more stimulation from playing more. Either way, limit your child's screen time.

Communication Technologies and Sleep

There is a review in the journal Sleep Review of modern communication and media technologies and sleep. The National Sleep Foundation did a poll this year about these technologies and how they affect Americans' sleep. They found that 95% of Americans, aged 13 - 64, use some type of electronic device (TV, cell phone, computer, or video game) during the hour before bed. The younger people tended to use more interactive communication media like social networking and video games, whereas the older people tended to watch more television in the hour before bed.

More than half of those who use the cell phone in the hour prior to bedtime leave the phone and the ringer on next to them while they sleep. About 10% said that they were awakened at least a few nights each week due to a phone call, email, or text message. Obviously, these sleep disrupting communication devices can worsen, or even cause, insomnia.

The problem with the interactive media and video games is that these devices tend to be more stimulating, and this can make it more difficult to sleep if these devices are used in the hour before bed. Also, we sit close enough to monitors on laptops and desk tops, that the light from the screen can interfere with melatonin secretion, the hormone that signals your brain that it's night and time for bed. That pre-sleep hour should be relaxing, with only dim light and minimal stimulation.

I see this as a large public health issue, especially with generation Z kids (age 13-18 year olds), who are intertwined with these interactive communication devices. Public education might be able to address this problem, as the right amount of sleep can be so important to mental health, physical health, and overall development.