Sure, there's plenty research pointing to the benefits of parents reading to their children, but a new study suggests all you tech-addicted parents may want to go old school for the bedtime story.
The research, posted online in the Proceedings of the National Academy of Science finds people who did their evening reading via a light-emitting electronic device had a harder time falling asleep and poorer quality sleep than those who read a print book.
It's the latest in a line of research on the effects of artificial, "blue-rich" light on sleep cycles. Everything from LED lamps to television, computer, tablet and smart phone screens—and even some children's night lights—are using more blue-spectrum light, which mimics natural bright sunlight.
Using blue-rich light in the morning—when we would naturally be exposed to bright sunlight—may actually help boost students' wakefulness and attention. But blue-light exposure after natural sunset, which, in our media-happy world is almost impossible to avoid, delays the release of melatonin, a sleep-inducing chemical.
Anne-Marie Chang, an assistant professor of biobehavioral health at Pennsylvania State University, Dr. Charles A. Czeisler, a professor of sleep medicine at Harvard Medical School, and other researchers tracked the sleep cycles of a dozen adults reading for four hours per night for five consecutive nights using one of seven common electronic devices, including Kindle, iPad, and iPhone readers, and then reading print books for four hours each evening for another five days. Each participant reported on both sleepiness and wakefulness at different periods, and their melatonin levels and physical alertness were tested.
During the time they used e-readers, the participants were less drowsy, took longer to fall asleep, and felt less awake in the morning than those who read print, researchers found. Moreover, the participants showed supressed melatonin levels when using eReaders, and their circadian cycles shifted later.
The authors noted that nine out of 10 Americans use some type of light-emitting electronics in the hour before bedtime more than once a week, and children's books increasingly come in tablet versions (including my own sons' favorite, Sandra Boynton's "The Going-To-Bed Book.") Though it represents a small group of participants, this study adds more evidence that educators may want to encourage families to unplug before they settle in for the bedtime story—at least if they want to be able to get them up for school the next day.