Play in the Light, Preserve Your Sight
A recent article in the magazine The Atlantic, “Nearsightedness and the Indoor Life”, lays out the evidence for a connection between the increasing frequency of myopia (nearsightedness) and a life lived indoors. The increase is dramatic. The prevalence of myopia in the U.S. increased 66% from the 1970s to the early 2000s. We touched on the subject ourselves in our blog post about the disappearance of recess.
The article in The Atlantic looks at some new studies to suggest that the increase in nearsightedness may have a lot to do with children spending too much time studying small electronic devices. In early childhood, the eye adapts to whatever conditions are “normal.” If close scrutiny of electronic devices is the norm, the eye “thinks” that nearsightedness is the normal need, and myopia becomes much more common.
The article also refers to a CNN interview with researcher Kathryn Rose who discusses evidence that spending 10-14 hours per week outdoors in natural (i.e. bright) sunlight protects against early onset of nearsightedness. The most dramatic study we know of comes from Taiwan. Half of 500 hundred school children were encouraged to go outdoors during recess. At the end of year, significantly fewer of those children had developed myopia than their peers who played inside. Similar findings have been shown by researchers in the UK. So Mom’s advice to go outdoors and play was absolutely right!
There are other conditions that are also dramatically on the rise. One that leaps to a child psychiatrist’s mind is ADHD. The CDC reports that the diagnosis of ADHD has increased by 41% in the past decade. Is it possible that some of this increase is also related to lack of time outdoors? We think it’s a reasonable hypothesis. There certainly is information showing that more time outdoors, especially time “in nature,” leads to an improvement in ADHD symptoms and a fascinating study that found areas with more sunshine have fewer diagnoses of ADHD. And there are adolescent mental health treatment centers that emphasize spending more time outdoors as one of their main curative factors.
There is also evidence of a rising rate of depression in childhood. Beyond the direct anti-depressant effects of bright light that we are always talking about, time with all those little screens may play another role. Children who spend less time in face-to-face interactions with others (in the old-fashioned non-screen sense of the term) are less likely to develop good social skills, which can certainly contribute to depression. The constant talking and comparing notes that goes on in adolescence can lead to a restoring of balance to a teenager who periodically loses all sense of confidence in him or herself (in the typical way that teenagers do.) If the peer contact is almost entirely through texting and social media, the sense of proportion that can be restored through in-person contact with a close friend may never happen. The area of the brain most responsible for social judgment, the orbitofrontal cortex, receives input from all five of the senses. We need all that information to develop sound social intuition about another person. An electronic message is never going to develop that orbitofrontal cortex in quite the same way as old-fashioned time with another human can. And of course most social media leaves even well-adjusted adolescents feeling lonely and worried because it looks like everyone else is having a much better time with much better friends. So time indoors with hand-held electronic devices may not lead to just optical nearsightedness. It might lead to emotional nearsightedness as well!