Sleep is important

The take-home message from these studies is that sleep before learning is critical for the brain to be able to lay down new memories. Without it, the inital coding of information suffers dramatiacally, resulting in memories that do not persist in the long term. Furthermore, the impact of inadequate sleep may be different types of learning, specifically positive forms of learning, meaning it’s harder to remember the happy events of the day without a good night’s rest.

M. Walker, “Sleep to remember,” American Scientist, vol. 94, no. 4, pp. 326-333, 2006. [Online]. Available: http://www.americanscientist.org/issues/feature/2006/4/sleep-to-remember

Note that napping can help if you aren’t getting enough sleep at night.