Sleep Deprived & Want to Sleep In, But Can’t? Here's Why Your Brain Won't Let You! by Nicole DeAvilla

After a late night do you ever wonder why you can’t sleep in or take a long nap during the day to catch up? Researchers wanted to know why, too! Sleep scientists from the University of Liege looked at brain scans of sleep-deprived people to help them better understand this phenomenon. The study was published in the journal Science.

What did they find? We have two internal timers inside our brains. The “clock” inside our brains is sensitive to daylight and tells us to be active in the day and rest at night. We also have an “hour glass” in our brain that keeps track of how much sleep we've had. As the hourglass runs out it tells us, “Hey, get some rest now!” These two internal timers are sometimes at odds with each other and it makes it hard to fully catch up. 

Your best bet is to get your full night’s sleep in the first place!