Researchers have long known that sleep plays a key role in memory consolidation and that the brain replays the day’s events and experiences as we slumber. Now a recent study at the University of Arizona, in which the neural activity of rats who were taught to follow a pattern in a maze, was monitored during the exercise and again during subsequent sleep. It was observed that memories may be replayed in sleep 6-7 times faster than they occurred in real time. The results may lead to a better understanding of the role of sleep in the consolidation of experience in to memory.
Science 2007 Nov. 16; 318(5853): 1147-50