Trouble sleeping? Maybe it's your iPad

(CNN) -- J.D. Moyer decided recently to conduct a little experiment with artificial light and his sleep cycle.
The sleep-deprived Oakland, California, resident had read that strong light -- whether it's beaming down from the sun or up from the screens of personal electronics -- can reset a person's internal sleep clock.
So, for one month, whenever the sun set, he turned off all the gadgets and lights in his house -- from the bulb hidden in his refrigerator to his laptop computer.