iPad owners who read their tablet computers for half an hour before going to sleep at bedtime felt less sleepy based on a new study. Their brains' electrical activity was different from people who read from physical books. However, both types of sleepers required about the same amount of time to fall asleep and got shut-eye for around the same length of time.
The study was conducted by the University of Bergen in Norway. It included 16 non-smokers between the ages 22 to 33 who knew how to use tablet CPUs; and had no sleep, medical, or mental conditions.
Study participants were given rules to follow before it started. They had to keep a regular sleep-wake schedule and stay in bed long enough to fall asleep.
Lead author Janne Gronli explained that light causes people to become alert. Her research team had predicted that using tablets at bedtime would make people less sleepy than reading traditional books. However, they were surprised that reading iPads did not cause people to fall asleep later, according to Newsmax.
Gronli also told Reuters Health by email that the "iPad condition" caused slow waves to start half an hour later.
The participants slept in their own beds during the study. Scientists recorded "polysomnographic" data for three nights. That included one night to collect a baseline, one night of reading an Apple iPad for half an hour, and one night of using standard reading light to read a physical book for 30 minutes.
A light meter took readings for eye-level illumination during each reading condition. It was about twice as high when people read from an iPad as when reading a book.
The tablet also gave off a high level of blue light. Gronli explained when the eye absorbs short-wavelength blue light it tells the brain that it is daytime by alerting its active areas. However, the average amount of sleep when reading the iPad and book was still about eight hours.
In related news last year a study's findings published in BMJ Open argued that people should not use tablets and smartphones in bedrooms. It found that teens that used a computer within an hour of bedtimes were three times more likely to sleep less than five hours, according to The Telegraph.
Here's how to fall asleep faster: