In news that should surprise no one, science has now definitively determined that reading from a tablet before your bedtime affects your sleep quality. Sure, “affects” is a bit loose as a term, and to be fair, it didn’t take tablet readers any longer to fall or asleep (nor did they sleep any less), but all the same, their brain activity was decidedly different from that of physical book readers. According to a new study from scientists at the University of Bergen in Norway, pre-bedtime iPad users “felt less sleepy and had different electrical activity in the brain during sleep” when compared to their friends who read from paper.
“Since light has an alerting effect, we predicted a lower sleepiness in the iPad condition at bedtime compared to the book condition,” lead author Janne Gronli of the University of Bergen in Norway told Reuters. This was accurate, Gronli noted, but despite not feeling as sleepy, tablet readers were still able to fall asleep at the same rate as non-iPad readers.
That said, Gronli continued, “We found a delay of 30 minutes in the generation of the restorative slow waves during sleep in the iPad condition.”
The study used a rather small sample size of just 16 subjects between the ages of 22 and 33. In conducting their experiment, researchers examined polysomnographic data from three nights of participants’ sleep — one for a control, one for 30 minutes of pre-sleep iPad reading, and one for 30 minutes of physical book reading. In this last situation, the room was illuminated by reading lights in the subjects’ own rooms. Ultimately, participants noted that they felt sleepier after reading an actual book, and after they read from an iPad, their EEG readings displayed “delayed and reduced slow wave activity, representing deep sleep, in the brain after sleep onset.”
