A reset button was found in the brain — it turns on during sleep and cleans unnecessary data, the study says.

In the hippocampus (this is the part of the brain that stores memories), neurons turn off during sleep so that the brain can "reset" and prepare for new information.

If you don't sleep, the brain gets overloaded and can't cope with new information — in experiments, mice forgot where objects were. Sleep is not just a rest.