Scientists have just solved a case of mistaken identity. It involves a creature that looks like a cross between a house cat and a teddy bear, and it lives high up in the cloud forests of the Andes.
For over 100 years, scientists thought this animal was a well-known member of the raccoon family. Specifically, they thought it was a critter called the "olingo." But one scientist recently took another look and realized he had an entirely new species on his hands.
What happens in our brains while we're asleep? That's one question neuroscientist Penelope Lewis is trying to answer. She directs the Sleep and Memory Lab at the University of Manchester in England. Her new book is The Secret World of Sleep: The Surprising Science of the Mind at Rest.
Lewis joins Fresh Air's Terry Gross to talk about how sleep affects memory, and how REM sleep can affect depression.