BOB HIRSHON (host):
Dream navigating. I’m Bob Hirshon and this is Science Update.
Navigating even a simple route takes a surprising amount of brain power, and scientists are just beginning to figure out how it’s done. In the journal Neuron, Florida State neuroscientist Aaron Wilber reports that in lab rats, the brain’s parietal cortex has clumps of neurons that fire together to signal a left turn, others for a right turn, and still others for straight ahead. When a rat learns a new route, the clumps fire in the proper sequence to get the rat to its destination—a sequence that’s repeated when the animal sleeps.
AARON WILBER (Florida State University):
So we saw that basically, the sequences of activity were getting played back, but not at normal speed; they were getting played back about four times faster than they happened in real life.
High speed replay lets the brain rehearse the route more times per dream, and may also explain why short dreams may seem much longer to us when we wake up. I’m Bob Hirshon, for AAAS, the science society.
Story by Bob Hirshon