Sleepy brains take learning seriously

For much of the time that we snooze, our brains generate an electrical output known as slow-wave activity. This sleep-specific pattern arises from neural processes involved in learning rather than in recharging fatigued brain cells as scientists have often assumed, a new study suggests.

Giulio Tononi of the University of Wisconsin in Madison and his coworkers instructed 11 adult volunteers to practice a hand-eye coordination task shortly before spending a night in a sleep laboratory.