Want better sleep? Avoid smartphones, tablets and e-readers before bed, as using the electronics may have a negative impact on sleep patterns and long-term health, according to a Penn State University study published in the Proceedings of the National Academy of Sciences.
During the 14-day study, neuroscientists studied 12 young participants tasked with reading for four hours using an electronic device in a dimly lit room. They started with an Apple iPad during the first five nights, and then read from printed books for five nights. Participants took 10 minutes longer to fall asleep, and didn't have as much time in REM sleep - the deeper and more restorative sleep phase in which humans dream.
"There's a lot of skepticism out there; a lot of people think this is psychological," said Charles Czeisler, director of the Harvard Medical School's Division of Sleep Medicine, in a statement to the media. "But what we showed is that reading from light-emitting, e-reader devices has profound biological effects."