I'm a napper. 20, 30 minutes a day -- that's all I need. But it banishes the post-lunch sleepies and makes me feel like someone's reset the clock inside my brain -- and now, thanks to researchers at Berkeley, we know that that's really kind of what happens, on a neuro-cognitive level. According to an article about the study, "An hour's nap in the afternoon can boost a person's brain power and improve their memory ... showing that short periods of sleep during the day can make it easier to function mentally."

Scientists found that a Spanish-style siesta after lunch does more than just refresh the body and mind, it also makes it easier for the brain to store and retrieve items of short-term information needed for working or studying. The findings lend weight to the idea that sleep not only restores a person's sense of well-being, but is essential if the brain is to take on additional information as part of the memory-forming process of learning.

It all happens in the hippocampus, which is a part of our brain which temporarily stores "fact-based memories." "It's as though the email inbox in your hippocampus is full and, until you sleep and clear out those fact emails, you're not going to receive any more mail. It's just going to bounce until you sleep and move it into another folder," Dr Matthew Walker, a Berkeley psychologist said.

Even more fascinating, the study found that small children who are learning to construct words into sentences are unlikely to remember their lessons unless they sleep soon afterward.

What about you -- how do naps affect your state of mind?