Sleepless Nights: Don’t Take Your Laptop to Bed. Bright Screens Cause Problems

When I get into bed at night, I like to read a little bit. I open a book. After awhile, I drift off. It’s one of the great pleasures in my life. I think it reminds me of when my parents read to me in bed when I was a little boy.

My latest reading is the fascinating biography of Lyndon Johnson written by Robert Caro. It’s a thick book, about 700 pages and it weighs a lot. So I enjoy it on a Kindle rather than hard cover. The Kindle I read from, which does not have backlighting, weighs eight ounces. When I drift off, I don’t get woken up with a start when it hits the floor as I do with the hardcover. But maybe that’s me. I also don’t read with a backlit Kindle. I find I don’t drift off when I do that. I just stay up reading. It’s an odd thing.

Now, I think I have an explanation for this. Researchers at Ohio State University published a paper last week which suggests that reading on a backlit screen keeps you up. Or, looked at another way, doesn’t let you drift off.

The study done by the researchers was not done with humans. It was done with hamsters. The hamsters were put into a box with the lights on just before they went to sleep every night. The lights were then kept on while they slept. These were low level lights, not bright lights. The hamsters woke up irritable and depressed.

How do you know a hamster is depressed? The “baseline” hamsters, those not left to sleep with the light on, drank lots of sugar water when they woke up. All hamsters like sugar water. But hamsters sleeping with the lights on, who also ordinarily drank lots of sugar water, now did not. They turned away from it after a little bit. In another test for depression, the hamsters were taken for a swim. Hamsters who slept in the dark paddled around happily. Hamsters who slept in the light just lay in the water floating. They just didn’t care much one way or the other, it seemed. The hamsters also experienced weight gain.

I know it’s a long way from a hamster—and I might note these were SIBERIAN hamsters—to a human. But then again, maybe not.

We know humans secrete a hormone called Melatonin, which goes into the Hippocampus part of the brain to settle things down. Hamsters also secrete Melatonin into their Hippocampuses to settle things down. For the Siberian hamsters, those who slept in the light secreted less Melatonin than those that didn’t.

After the experiment, the researchers dissected the brains of the Siberian hamsters and they found less of these little hairy things called dendritic spines on the Hippocampuses of their brains. Dendritic spines help one part of the brain to communicate with another. So there was less communication. Months later, they found these dendritic spines had not come back. The hamsters were permanently more depressed and irritable.

(Now you know why the researchers, a team led by Dr. Randy Nelson, professorof neuroscience and psychology at Ohio State, did not do this experiment on humans. “So you want to pay me five bucks and I have to do WHAT?”)

So, important safety tip—if you want a hairy brain that’ll keep you happy, don’t read on a backlit computer when it’s time to go to bed. That’s it.

(I showed this to my wife. When I read on my non-backlit Kindle before we go to sleep, my wife takes out her newer model Kindle, the Kindle Fire, which IS backlit. I’m thinking of throwing it into the fire.)

The whole thing does bring to mind a series of experiments I read about (non-backlit) by a Dr. Joseph Buckley, the chairman of the Department of Pharmacology at the University of Pittsburgh. This study was done a number of years ago.

Dr. Buckley wanted to see if an urban environment—all the hustle and bustle of the city—would have an affect on the blood pressure of laboratory mice. He created a box into which he put mice. The box had blinking lights, shook slightly at the rate of 140 a minute (to simulate a bus or subway ride) and had a series of loud city sounds, such as cars honking, various bells and buzzers, the sound of a jet plane taking off and so forth. Not surprisingly, Dr. Buckley found that blood pressure levels of the mice rose alarmingly when they were put into this environment. When he took them out, the high blood pressure levels subsided. Dr. Buckley noted also that his own blood pressure levels went up while he was conducting these experiments.

Having read these two reports, I decided to see if I could create a rural environment to see if that might have the opposite effect on laboratory rats.

I got a large cardboard box, one that had been used to ship a refrigerator, set it on its side in my library and cut off the top. Along the walls inside, I hung a variety of oak branches and leaves, which I got to make soft rustling noises by attaching a fan at the top. On the bottom of the box, at one end, I sprinkled some sand I brought up from the beach. And on the bottom of the box at the other end, I tamped down rich dirt from a farm with good grass growing on it. Then I turned out the lights and closed the curtains.

I didn’t have any rats of course. But I did have a dog. Rats, dogs, what was the difference.

The first time I put my dog in this box, he immediately lay down and went to sleep. He also did this the second time I placed him the box. But after a few more experiences in the box, my dog began to show alarming trends. He showed a distinct interest, once he was removed from the box, in post cards and souvenirs of the area. He took to wearing sunglasses and going out to discotheques at night.

He’s been missing for three days now. If you locate him please give me a text or email at dan@danspapers.com. You can’t miss him. He drives a little red sports car.

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