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I became obsessed with learning about why we limit screen time and how it affects vision health after a couple of family members, young and older, were diagnosed with 3D perception problems. The technical terms are alternating amblyopia and strabismus.
I started learning everything I could to help them and to prevent similar problems in our children. I read a LOT of books and articles.
The two most useful books I read were Fixing My Gaze and Eyes for Learning. Fixing My Gaze is by a brain scientist who did not learn to see in 3D until she was middle aged and underwent vision therapy. In in Eyes for Learning, I found out about Snapp Reading and learned about healthy vision habits.
There are studies about how rapid scene changes in TV shows and movies are too hard for kids to follow and not good for the developing brain.
What kids need most is to be doing things with their hands and bodies actively moving in space. As one of the books pointed out, screen time warnings are not just the dangers of being sedentary, it's the dangers of all the movement and development they're not doing to develop hand-eye coordination, balance, proprioception, etc.
Glowing screens affect the pineal gland and the hormones associated with circadian rhythm and depression levels.
Researchers wanted to make the recommended age for TV viewing age 8, but they knew no one would like that so they said age 2, Don't believe me? Look it up. I think it was in Eyes for Learning, but there are mentions other places, too.
There's a lot of great advice about healthy vision habits and myopia prevention in children at the endmyopia website.
I already had reasons to limit screen time, but this video on the Waldorf philosophy gives even more. I love to share this video with my friends when they need to renew their motivation to limit screen time.
That viewer warning at the beginning cracks me up, but it's true.
They will have the rest of their lives to watch movies. When they're young, they need a chance to develop their imagination and creativity and to learn how to think for themselves.
I was also struck by the nature documentary comments because that's what we probably would have watched before I saw this and thought about it. Instead, we're going for walks and observing nature in person.