Sleep helps the human mind learn complicated skills and recover learning we thought we had forgotten from the previous day, concludes a new study by the University of Chicago. Howard Nusbaum, professor of psychology at the university, explains that “Sleep consolidates learning by restoring what was lost over the course of a day and by protecting what was learned against subsequent loss.”

Researchers tested their theory by asking 200 college students to learn a new video game containing a rich, multisensory virtual environment, in which players had to use both hands to deal with continually changing visual and auditory signals. The volunteers, most of whom had no previous gaming experience, were divided into three groups, each trained and tested at different times of the day. The groups that were allowed to get a good night’s sleep before being tested again the next morning achieved the highest performance scores.