Ipad can cause Insomnia to users

The bright light emitted by an iPad could give some people reading before bedtime a bout of insomnia, researchers suggest.

This is because the iPad uses a back-lit display rather than the "e-paper" found in other popular e-readers such as the Kindle that mimic the printed, duller page by reflecting light from elsewhere.

Sleep researchers have long known that light inhibits the release of melatonin, a hormone that settles the body into sleep mode toward evening time. "Melatonin is pro-sleep," said Frisca Yan-Go, director of the UCLA Sleep Disorders Center.

Any artificial light source at night, whether it be from a television or a bedside lamp, can mess with the body's melatonin production, Yan-Go said, which rises when darkness falls, then tapers off toward morning as part of a natural cycle called the Circadian rhythm.

According to Yan-Go and other sleep researchers, the reason for concern with the iPad over other forms of late-night light is that readers hold the device relatively close to their face. In theory, this could mean that the iPad affects the body's melatonin cycle more than watching late-night reruns on a television that is clear across the room, Yan-Go said.

The fact that the iPad has a full-color screen — blue light in particular sparks alertness — and offers Web browsing and other engaging computer activity, unlike other dedicated e-readers, could also keep people from getting a good night's rest, scientists say.

Yan-go said that she has not yet had patients complain about iPad-induced insomnia — perhaps because the device is so new — but she nevertheless recommends against using it as an e-reader given past cases of patient restlessness related to laptops and television. "You really want the [sleep] environment to be quiet and dark," Yan-go said.

source:cnet