Brain rhythms are key to learning
Neuroscientists have long known of the existence of brain waves — rhythmic fluctuations of electrical activity believed to reflect the brain’s state. For example, during rest, brain activity slows down to an alpha rhythm of about eight to 10 hertz, or cycles per second. It has been unclear what role, if any, these waves play in cognitive functions such as learning and memory. But now, a study from MIT neuroscientists shows that a switch between two of these rhythms is critical for learning habitual behavior. In a paper appearing this week in the Proceedings of the National Academy of Sciences (PNAS), the researchers report that as rats learn to run a maze, activity in a brain region that controls habit formation shifts from a fast, chaotic rhythm to a slower, more synchronized pace. That switch, which occurs just as the rats start to master the maze, likely signals that a...