Don't feel guilty about the breaks you've been sneaking at work—they could be helping you learn. Neuroscientists at MIT find that rats take a similar pause after exploring an unfamiliar maze. During that break, the animals' brains repeatedly review a backward version of the route they just took, most likely cementing memories of the steps needed to reach the goal.
David Foster and his team zero in on this process by placing tiny wires into the rats' brains and then eavesdropping on individual cells. The neurons that light up during the experiments lie in a region known to form short-term memories. But as those cells play the memory again and again—10 times faster than the original experience—the rest of the brain has lots of opportunities to absorb the information and to place it into long-term storage. "This implies that it's not just during an experience that learning occurs," Foster says. "If we're right, the period after the experience is just as important, maybe more important."
The results may explain previous studies showing that people and animals learn best when given breaks between tasks—and provide a persuasive new justification for office daydreaming.