Napping can significantly increase learning, memory, awareness, and more

For cognitive memory processing, however, a 60-minute nap may do you more good, Dr. Mednick said. Including deep, slow-wave sleep allows you to recall memories, places, and faces. The downside: a little sleepiness upon waking.

“If you nap for more than 30 minutes, you end up in a deep sleep. Have you ever taken a nap and felt worse when you woke up? That’s what happens: you oversleep and enter a phase of sleep that’s very difficult to come out of,” Dr. Michael Breus.

Finally, the 90-minute nap will likely involve a full sleep cycle, which promotes creativity and procedural and emotional memory, such as learning to ride a bike. Waking up from REM sleep typically means minimal sleep inertia, Dr. Medneck said.