Why do we dream? Do dreams hold psychological meaning or are they merely the reflection of random brain activity? What purpose do dreams serve? Questions on the origins and meaning of dreams are as old as humankind, and as confounding and exciting today as when nineteenth-century scientists first attempted to unravel them.

Our brains spend the entire time we're asleep processing the memories we formed during the day before, strengthening them, filing them, discovering patterns, and generally figuring out what they mean all so that they will be more useful to us in our future waking lives.

In this week's episode of Spectrum of Health, Dr. Christine Schaffner talks with Dr. Bob Stickgold to discuss how our dreams play an integral role in our nightly memory processing, as well as how these new memories might fit with what we already know.

Dr. Bob Stickgold is a cognitive neuroscientist and professor of psychiatry at Harvard Medical School. He is the co-author of When Brains Dream as well as published over a hundred scientific papers on sleep and dreams.