Understanding the Science About Kids and Screens

Some say that technology is destroying childhood. Others say it doesn't harm it at all. Both sides misuse research to back their cause. Cherry picking research to prove a point isn't unique to the debate about kids and technology. But, in this case, anyone with an opinion can find a study to back them up. And if that fails, there's always circumstantial and anecdotal evidence. It's possible to cite research that proves an "irrefutable" link between media violence and aggressive behavior. It's just as possible to cite studies showing "no evidence" of such a link. Likewise, studies are sensationalized and turned into clickbait headlines. For example, "A New Kind of Social Anxiety in the Classroom" in The Atlantic purports to show that "Kids who constantly use phones and computers tend to be more nervous in face-to-face conversations." But the article actually says: "There’s no proof that an increased use of technology over the past five years has led to a greater prevalence of social anxiety." Unfortunately, it can take years and even decades to evaluate results from studies about human health and behavior. Because of this, there's simply a lot that science can't yet tell us about the long-term impact of different technologies on our mental and physical well-being. (Though we can observe some short-term effects — see below. And some kids truly do become addicted to the internet.)

It's also difficult to find excellent data detailing the effects of exposure to digital technology on childhood development. That's partly because this technology is just a couple of human generations old. It's also because study methodology is often narrowly focused or very broadly focused.

For example, people often cite studies of "screen time," without differentiating the type of screens or behavior they're referring to. Does that screen time mean watching television, or playing Xbox? Texting on an iPhone, or doing homework on a MacBook?

Some of the most commonly cited studies about the "educational merits of screens" are referring to educational TV programing, before the iPhone even existed. It works both ways.

I'm not saying we should throw our hands up and take the lame, willfully ignorant stance of "I'm not a scientist." Likewise, we shouldn't say "I have a personal anecdote that counters the results of your rigorous, respectable scientific study. Therefore, your entire study is useless." But we should keep in mind that every study has trade-offs and flaws. When it comes to human behavior, laboratory experiments often don't match real-life behavior. And our personal, anecdotal experience is important but limited.

The Most Documented Effects of Excess Screen Time on Kids is on Physical Health

So far, the best-documented risks of excess screen time are physical. The negative impact of a sedentary lifestyle is very well documented, and screen time is sedentary by default. Heavy screen use in youth may establish life-long negative habits, and weight gained in childhood is difficult to lose later in life.

The most documented risks are:

• Weight gain — though this is still best documented as a result of TV viewing habits
• Unhealthy sleep habits
• Carpel tunnel issues — pain in fingers and wrists
• Poor posture
• "Tech neck."
• Eye strain (which is different from eye damage, but the long-term consequences of narrowed blood vessels in eyes is unknown)
• Degraded

What about negative impacts of technology on kids' mental health?

Little can definitively be proven at this point, but there are indications that excess screen time impacts kids' mental health, at least for the short term. Areas of potential harm include:

• Lowered ability to focus on what is most important
• Reduced ability to recognize social cues
• Delayed development

Some Kids Are More Vulnerable

It should be noted that some kids exhibit addictive or escapist attachments to technology. Likewise, some kids may be more vulnerable video-game inspired aggression. This study found this to be true for kids with three "Big Five" traits: "high neuroticism (prone to anger and depression, highly emotional, and easily upset), disagreeableness (cold, indifferent to other people), and low levels of conscientiousness (prone to acting without thinking, failing to deliver on promises, breaking rules)."

Our always-on, intensely computer connected world is a totally new human experience.

But we don't need to rely on double-blind scientific studies to know what's good for our kids. Most of us agree on common sense limits on screen time. So let's keep track of the latest research, with an awareness that the full story of technology's impact on our kids' health is still developing. (I read a study that told me that's the right thing to do.)

• Take our Quick Survey About Screen Time and Kids
• For a bit of comedy on the topic, read The Onion's take on the Pros And Cons Of Screen Time For Kids
• Read "Unplug the Kids"
• Alarmism is Taking a Toll on Dialogue About Screen Time and Kids