When we’re tired, we tend to make mistakes. We get up, pour a cup of coffee and leave it on the kitchen counter. We put the milk in the pantry and the cereal in the refrigerator. We think one thing and say another. We lock our keys in the car. Stop me if any of this sounds familiar.
Researchers at the University of Wisconsin-Madison think they may know why we suffer these brain lapses – certain areas of our brains may actually be taking a quick snooze.
“We know that when we are sleepy, we make mistakes, our attention wanders and our vigilance goes down,” says Dr. Chiara Cirelli, professor of psychiatry at the university’s School of Medicine and Public Health. “We have seen with EEGs [electroencephalograms, which monitor brain activity] that even while we are awake, we can experience shorts periods of ‘micro sleep.'”
In the study, published in the journal Nature, researchers monitored rats that were kept awake for long periods of time (researchers kept giving them new toys to keep them active). Early in the study, the rats could easily reach through a hole with one paw to get a sugar pellet, but after being kept awake for a while they started dropping the pellets or missing them entirely.
Using electrodes implanted in the rats’ brains, Cirelli’s team noticed only a few cells seemed to slip into sleep territory at any given time. Out of 20 neurons monitored in one experiment, 18 stayed “awake”. The other two functioned as if the rat was asleep.
While the rats were definitely awake, moving and reaching for sugar pellets, their brain cells were apparently cycling in and out of sleep cycles in small clusters.
What’s really interesting is that the rats weren’t consistently bad at grabbing those pellets. As long as the right areas of the brain associated with motor control were “awake” they could complete the maneuver. As soon as those cell clusters went offline for a little nap, the rats fumbled.
That’s the major issue identified by the study. You can be seemingly awake, going about your day, and if you haven’t had enough rest (a rampant problem these days), your brain cells could be snoozing. It might be something as simple as leaving your coffee behind on the kitchen counter, but it could just as easily lead to a traffic accident or other serious incident.
The best way to keep your brain from catching that catnap while you’re awake is to make sure you’re getting enough quality sleep. If you’re struggling with falling or staying asleep, try some of these tips from the National Sleep Foundation.