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Q & A: Watching TV too close

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Most recent answer: 10/22/2007
Q:
Hi. My mom told me that watching too much TV and sitting too close to the TV would ruin my eyesight. Is this true? Also, why do I get dizzy when I am playing with video games all day?
- Crystal San Juan (age 7)
Burbank, CA
A:
Watching TV very closely probably isn't worse for your eyes than reading a book at close distances. There is a lot more to it than that, however. It is recommended that when reading a book, you "give your eyes a rest" by looking away every fifteen minutes or so, allowing your eyes to focus on something far away. All too often, when a natural break comes in a TV program, our reaction is not to look away to give our eyes a rest, but to flip the channel to another which is not showing an advertisement. This is not a good habit.

Our eyes are designed to focus at a great variety of distances. To focus constantly at a short distance can make the lens focusing muscles get fatigued. The sad fact is that people watch about 6 hours of TV a day, and if you do that very close to the TV and without ever looking away, your eyes can get quite fatigued.

There are other reasons to walk away from the TV of course. One is that it flickers sixty times a second, and may contribute to headaches if it's the only thing in your field of view. Some TV's also emit a high-pitched whine at the scan rate, which is also not good for the headache-prone. Perhaps the most important reason for not watching the darned thing is that the programming is usually abysmal. You can probably find much better things to do.

Playing video games is perhaps even worse. Modern three-dimensional first-person games animate the whole screen. As the character in the game moves, the background on the screen moves up, down, turns, and bounces. This plays a dirty trick on our biological protection mechanisms. One is our sense of balance. We have delicate components in our inner ear which tell us which way gravity is pointing, to help us with our balance. We expect, from long experience, for these cues from our inner ears to match up with what we are seeing. If these don't match, dizziness and nausea result, as they do in seasickness and other forms of motion sickness. Taking a break usually makes the effect go away.

Tom

(published on 10/22/2007)

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