What are the effects of prolonged computer exposure? (especially on the eyes)
I haven’t found a definitive answer for this and would really like to know.
A subscription to the Straight Dope message board.
Had to do it…
One thing I was told by my eye doctor is that the old wives tales about radiation from CRTs aren’t true.
I had an opportunity once to stick a geiger counter up to a computer monitor (CRT type). The results were rather enlightening. The geiger counter went nutso. My first reaction of course was :eek: but then when I moved the geiger counter back about six inches away from the monitor the ticks had pretty much dropped back down to background level. Unless you are doing something weird with your monitor, you aren’t getting enough radiation exposure to be meaningful. LCD monitors don’t emit any “radiation” of this sort.
RF emissions from the computer also get talked about a lot. According to some of the anti cell phone folks we should all be dropping like flies from the dangerous RF that comes out of our phones. The RF that comes out of your computer is essentially the same stuff, though it generally doesn’t have anywhere near as much energy as the RF coming out of your phone since your computer is going to great lengths to keep the RF inside its box, where your cell phone is trying to transmit it all the way out to the nearest cell tower. In either case, RF hasn’t proven to be dangerous at all unless you get enough of it to cook you (that’s how a microwave oven works), so in small doses like what comes out of your computer or cell phone it’s completley harmless.
There are two harmful things that I know about that are computer related. The first is that if you are constantly focusing your eyes up close, you tend to strengthen your eye muscles to look up close and your distance vision tends to atrophy a bit. You may find yourself getting a bit nearsighted if you use computers a lot. The second harmful effect of computers is that some people tend to develop carpal tunnel syndrome and possibly other physical problems like back pain. This only happens to some folks though. I personally type on a computer all day long at work and then spend a lot of time on the computer when I get home too, and have done this for several decades without suffering from any harm, although I do wear glasses (I wasn’t kidding about that nearsighted bit).
Thanks for the replies! Has there been any evidence it has any impact on the brain?
Engineer_comp_geek gets onto a relevant topic. Frequent computer use has the potential to cause or exacerbate all sorts of physical problems, unrelated to sight. Even in a decent workstation environment, RSI, tendonitis, carpal tunnel and all sorts of other problems can be debilitating. They’re the ones I worry about.
Interesting things you mentioned. The above, however, makes me wonder about all the years that people have spent as much time reading books as they do now staring at a monitor. Same problem?
Also, it has been addressed often, but some may not have read about it. It is strongly advised for people working long hours at a computer, to frequently look away at the other end of the room to exercise them ol’ eyeballs.
I can think of quite a few web sites that will make your brain rot. 
Seriously, though, I’m not aware of any harmful affects that computers have on your brain.
The old stereotype of “bookish” people always needing glasses probably has some basis in reality.
John Milton allegedly went blind from reading 16 hours a day, way before CRTs and LCDs were even conceived of. . .
Probably now but not always. I’ve cleaned some screens that just had to be turned off first or the shock would knock you back. (The voltages on the earlier CRTs where much higher.)
I have worked in places that stagger the computers to make sure the back of a monitor does not aim directly at an employees cranium. A few years ago studies suggested that it was probably not harmful. But ,there are people more sensative to somethings and this may be one. Better to be careful.
In case you or anyone else is wondering why this occured, rest assured it had nothing (or at least very little) to do with ionizing radiation. Geiger tubes are electrostatic devices; basically, an electric field is set up across a gas contained ina glass envelope so that the applied voltage is just below the gas medium’s breakdown voltage. An ionizing particle leaves a conductive trail of ions between the two electrodes in the tube, a small current flows and CLICK. Since the tube is already near breakdown, any large externally applied electric field (such as that found near a CRT screen) can also cause erratic conduction inside the tube.