What Screen Time and Screen Media Do To Your Child’s Brain and Sensory Processing Ability
(April 2 – Correction: Information on the AAP policies below has been edited. Thanks to the readers – Diana and P – who caught the error!)
It’s a scene we’re sure you’ve witnessed again and again:
A family is sitting in a restaurant having dinner. The four year old is clearly fed up with sitting, and starts to complain, jump on her seat or run around. But a few moments later, she’s quietly in her seat again, enabling her parents and older siblings to enjoy a peaceful meal and conversation for the next 30 minutes.
Her father handed her his iPhone.
It’s a scene we see repeated in doctors’ waiting rooms, supermarkets, public transportation… and while we entirely understand it, it also saddens us.
So many caring, well-meaning parents are unaware of the developmental damage caused to their children by exposure to screen time and screen media.
Televisions. Computer monitors. Tablets. Smartphones. Dumb phones. Children’s toy computers. Kindles. The Apple watch.
If it gives off electromagnetic radiation in the visual spectrum, it’s a screen.
In many ways screens have changed our lives for the better. In other ways, they’ve changed our lives and the lives of our children – and not necessarily for the better.
The original official policy of the American Academy of Pediatrics (made in 1999 and reaffirmed in 2011) states that “pediatricians should urge parents to avoid television [or other media] viewing for children under the age of two years.” Children between 2 and 5 should be limited to “no more than 1 hour per day.”
In 2016 they issued a policy adjustment stating that pediatricians should discourage any media use under the age of 18 months, except for video-chatting (as often happens with far-away relatives). Between 18 and 24 months, if a parent wants to introduce screen media, then they should choose high-quality apps and use it together with their toddlers. (Although the policy indicates that the educational benefits for children under the age of 24 months are low, and come mainly from parent interaction with the child, and not from the media itself.)
While the original policy of the AAP called for children older than 5 to be viewing no more than 2 hours of media daily, the updated 2016 recommendations explains that in today’s world, when media is everywhere, a one-size-fits-all approach doesn’t work. Families need to make themselves aware of the risks and benefits of media use, and create individualized plans for their children, including enough sleep and physical exercise.
Reasons given by the AAP – and other research studies – include associations with obesity, sleep issues, aggressive behaviors, less time spent in developmentally helpful interaction with parents and siblings, language delays and attention issues.
Reference is made to the potentially harmful effect of media exposure during the rapid brain development period of age 0-2, but most studies – and even the AAP policies – don’t delve into the details of the impact on your child’s brain.
We’d like to give you a peek behind the scenes, and show you what happens to the brain when it’s in the process of viewing screen media.
Screens Give Your Body the Blues
We’ve all been fooled by the “what color is white light?” question. Answer: all of them! Natural daylight, provided by our sun, is made up of all the colors of the visual spectrum, although there does tend to be a little more blue light emitted than the other colors.
The blue light of natural sunlight does some great things for our body. It boosts attention, reaction times and mood, and it suppresses melatonin (the hormone that regulates your circadian rhythms and makes you sleepy when it increases) so you can be awake and alert during your active hours.
That’s great for your body – in the daytime. When your body is supposed to be winding down for sleep, however, it’s another story.
Most of today’s devices are illuminated by LEDs, which have a much higher percentage of blue lightwaves than any other light source – natural or artificial. Here’s what “white” light is really made of in the following artificial light sources:
(The above image comes from the Molecular Vision Journal. The markup is our own.)
White LEDs are almost entirely blue light, combined with a chemical compound to make it look white.
Night-time exposure to LED-illuminated devices (most of the screens out there today: computers, tablets, phones, flat screen TVs, e-readers, video games) suppresses melatonin and disrupts the natural sleep cycle.
This Scientific American article describes the following study where volunteers spent several evenings reading for a prolonged period of time before a 10PM imposed bedtime. Some used printed books and some used e-readers. Those who used e-readers took longer to fall asleep, had less REM sleep and felt sleepier and less alert for hours after they woke up in the morning – even if they had gotten the same amount of sleep.
We repeatedly see sleep cycle issues in the children who come to our clinic. When we probe, we almost inevitably hear that they’re playing video games, using social media or watching TV for an extended period before they go to bed. Sleep cycle disruptions are a significant contributor to ADHD and other mood and behavioral issues.
One of the first things we work with these parents and children on is significantly reducing screen time before bed. Blue light – it’s not for night!
Okay, fine, you might be saying. I’ll curtail the screens at night, and let my children play their video games, use the computer and watch TV in the afternoon.
We wish it were that simple.
If your child’s screen use is focused on reading chapter books off a Kindle or typing in a word processing program, no problem. (Again, as long as it’s not at night when the blue wavelengths in the white LEDs will impact sleep patterns.)
But who among our kids spends his primary media time doing that? Our kids are playing fast-paced video games, watching cartoons and TV shows with plenty of action and jumping from photo to chat to status update on social media.
The rapid-fire changes that happen in most screen activities, from video games to recorded entertainment to social media updates, affect two parts of the brain:
- the visual processing system
- the vestibular system