According tothis articlein Bangkok Post, just a few minutes of sleep can improve your memory and mental performance. Dr. Olaf Lahl at the University of Dusseldorf (Germany) conducted an experiment in which volunteers were asked to remember a list of 30 words. Then, the volunteers played solitaire for one hour. During the one hour period, some of the volunteers were allowed to take a 6 minute nap, while others were asked to stay awake. The experiment found that subjects who took a brief nap displayed “superior recall” when compared to subjects that stayed awake.