BBC Future column: Hypnic Jerks | Science News | Scoop.it

As we give up our bodies to sleep, sudden twitches escape our brains, causing our arms and legs to jerk. Some people are startled by them, others are embarrassed. Me, I am fascinated by these twitches, known as hypnic jerks. Nobody knows for sure what causes them, but to me they represent the side effects of a hidden battle for control in the brain that happens each night on the cusp between wakefulness and dreams.