Our old, well-worn first-gen iPad has gotten a LOT of use over the years, and admittedly much of the use has been in bed at night. I read quite a bit, and though I still prefer good old-fashioned paper print books (I’m always in the middle of 2 or 3), our iPad has also become a regular staple in my routine prior to turning off the lights for the night, primarily for e-mails and this blogsite adventure I started several months ago. My wife and I have never had problems falling asleep as a result of iPad use, but many of my patients have found their insomnia improves with modifications in their habit of using electronic devices involving bright backlit screens in bed.
We’ve all experienced activities that cause us to end up going to sleep later than what we intended. However, backlit electronic pads can contribute to difficulties falling asleep if used shortly prior to bedtime, and there are a couple reasons why. First, the content of what you’re doing or reading can obviously play a role. Whether it’s an exciting video or the discovery of the latest shoe sale on Zappos, anything that you’re exposed to that is visually or emotionally stimulating or is of emotional importance to you can create an alerting effect that delays the onset of drowsiness. Second, and importantly, the light exposure from the backlit screen (particularly when full-color) can also have a stimulating effect.
Light tends to inhibit the release of melatonin in your brain. There is a thin band of neurologic tissue–called the retinohypothalamic tract–that connects your eyeballs to the hypothalamus, the seat of your body block. This tract is stimulated when the back of your eye–the retina (the cells of which are illustrated above)–are exposed to bright light, and the resulting signal to the brain leads to a sensation of wakefulness and alertness, the exact opposite of what you want when your goal is to fall asleep for the night. This is why it’s important to avoid bright light late at night and to expose yourself to bright light early in the morning if you have insomnia.
The problem is that modern backlit e-readers are not only capable of emitting very bright multi-colored light, but also held very close to your eyes: unlike your television set, which is across the room, your iPad is on your lap or held right in front of your face, bathing your retinas with light.
So here are some suggestions for you if you’re having difficulties falling asleep following backlit e-reader use at bedtime:1. Turn down the intensity or brightness of the screen. 2. Try an e-reader without a backlit display, such as a basic Kindle. 3. Call me old-fashioned, but you could always go back to paper books, and save your e-mail for tomorrow morning. 4. Read in relatively dim light. 5. In general, avoid intense light for about 1-2 hours prior to your projected bedtime.
Happy reading, everyone!