Do computers really fry your brain?

Rachel Balik, 27, sleeps with her BlackBerry by her bed - when she sleeps at all. She works in San Francisco as an assistant marketing manager for a tech startup. At 6 a.m. she reaches for the BlackBerry, buzzing with e-mails from the East Coast, and won't disconnect from it or any of her other devices until she turns in around 1 a.m. the next day.

Every weekday Balik listens to her iPod while reading on her iPad on her commute to work on the BART. At the office she stays planted in front of her laptop for most of her eight-hour day, looking away only for a meeting or cup of coffee. Her only technology relief is a nightly yoga class. But even then, when she closes her eyes for meditation, she envisions flashing browsers. Later, at home, she's on her laptop until the moment she climbs in bed.

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Like most of us, Balik is plugged in around the clock. And while a host of articles have analyzed the social and psychological effects of increased and prolonged technology use - the potential damage to family life and our ability to focus - and how screen time is linked to obesity, few have asked whether staring at screens for most of the day (and night) results in further physical harm.

In short: It does. Family physicians, ophthalmologists and neurologists conclude that there are clear signs of physical damage associated with frequent technology use, yet no one has studied these effects long-term.

"The technology boom is affecting our health in a major way," says Svetlana Kogan, M.D., internist and founder of Doctors at Trump Place in New York. She reports seeing more and more patients who suffer from frequent headaches, eye twitching, carpal tunnel syndrome, anxiety and insomnia, which she believes are linked to near-constant use of information technology.

In 2005 a medical term was coined to diagnose some of these problems, now known as Computer Vision Syndrome (CVS). A review of the syndrome in the Survey of Ophthalmology, a peer-reviewed journal, calls it "a repetitive strain disorder that appears to be growing rapidly, with some studies estimating that 90% of the 70 million U.S. workers using computers for more than three hours per day experience it in some form."

If you spend several days a week gaping for hours at a computer screen, you're likely familiar with the symptoms. Eyestrain and eye fatigue, irritation, blurred vision, head and neck aches and nausea can all be associated with prolonged computer use.

"People are sitting in front of a computer all day," says Ojai, Calif.-based optometrist Roger Phelps, who has been practicing for decades. "You are looking at a light source, not focused at the proper distance, and staring. It causes strain."

Balik experiences many of these problems. She often squints at the screen until her eyes water and blur. She suffers from severe migraines and says she rarely feels rested.

Phelps believes that the damage caused by CVS is temporary and can be reversed. The main issue, he says, is that people tend to stare at electronic screens, not blinking or looking away as often as they might while reading a book or magazine.

Image: Sit in a Bright Room

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