It’s obvious that parts of your brain continue to function while you sleep. After all you keep breathing, your heart keeps beating, and so on. But do you really “think” while you sleep? It probably depends, at least in part, on your definition of “think.” Researchers at the University of Cambridge and the Ecole Normale Supérieure in Paris recorded the EEG (brain waves) on a group of participants while they were awake. They were instructed to classify spoken words as either objects or animals by pressing a button. They were to use the right hand to press the button for animals and the left hand to press the button for objects. Testing continued while the participants were sleeping. What the researchers found—tomorrow.
Kouider et al. Inducing task-relevant responses to speech in the sleeping brain, Current Biology, 2014, DOI: 10.1016/j.cub.2014.08.016