Narrator: This is Science Today. We spend approximately one third of our lives asleep. But why? What is the exact function? And is there more to it than just refreshing the body and mind? Matthew Walker, director of the University of California, Berkeley's Sleep and Neuroimaging Laboratory, is using magnetic resonance imaging to understand just how sleep affects brain function.
Walker: There's really only a select handful of scientists around the world who are trying to understand the functions of sleep - particularly the role of sleep in learning and memory from a brain-anchored perspective and trying to understand what it is about - the electrical activity of the brain, what is it about the chemical cocktail swirling around the brain during sleep? What is it about the different parts of the brain that are lighting up or shifting down during sleep? So, to really try to get a handle from a really solid, mechanistic point of view - a brain point of view - what sleep is doing and for that, you need these sophisticated technologies such as magnetic resonance imaging, MRI scanning and such.
Narrator: For Science Today, I'm Larissa Branin.