The sleeping brain can perform complex tasks, particularly if the task is automated, the study says. Further research will now focus on how to take advantage of our sleeping time. Writing in the journal Current Biology, the research team set out to study the brain’s behaviour while awake and during sleep.
Using an electroencephalogram (EEG), they recorded the brain activity of participants while they were asked to classify spoken words as either animals or objects by pressing a button. Participants were asked to press a button in their right hand for animals and in their left hand for objects.
This allowed researchers to track the responses and map each word category to a specific movement in the brain. Then participants were asked to lie down in a darkened room with their eyes closed and continue the word classification task as they drifted off to sleep. Once asleep, a new list of words was tested on participants to ensure that the brain had to work out the meaning of the words before classifying them using the buttons.