Does this sound familiar?  You just had a heavy lunch and you feel sleepy and lethargic.  Well then, take a short nap, even if its just for 10 minutes.  Midday naps have long been recommended as beneficial both for the mind and body.  It improves your memory, makes you learn better,  lowers blood pressure and brings down the risk of heart attack.

Amazingly, researchers have discovered  that snoozing long enough will permit your memory banks to do their organizing, leaving your brain properly filed and ready to learn in the latter half of the day.

In a test done by  the University of California at Berkeley, Psychology professor Matthew Walker and his colleagues put 39 adults through a demanding learning task and tested them on it at noon.

And then, 2 hours later, at 2 pm, they divided the students into two groups and invited half of them to have a 90-minute nap while they made the remainder  stay awake.

A few hours later, at 6pm, both groups were returned to the day's learning task and tested again.

This was what they discovered.  The group that had their afternoon  siesta went into the 6pm task in better shape, both physically and mentally, to learn and performed 10 per cent better on the test than they had earlier.  The group who did not have a nap had a 10 per cent decline in their performance.  Prof Walker reported.

While the researchers conceded that not everyone had the same quality sleep, in terms of length of time and level of sleep, those who had more Stage 2 non-rapid eye movement sleep (a higher form of sleep in which one does not dream) had the greatest performance enhancement.

It seems that the brain naturally crave for sleep at certain times of the day in order to restructure learning information, in other words, perform brain information filing.  Much like how a super efficient secretary organizes vast amounts of information in a filing cabinet. This helps the brain to store and retrieve information better.  Sleep also prepares the brain for tasks ahead, be it learning or staying alert for danger.  For students, a midday nap means better learning and remembering.  And for office workers, better efficiency and productivity and less stress and mistakes at work.

In general, a midday nap has many physiological benefits for the mind and body.  It's like taking 1 step back in order to move 2 steps forward.  Midday naps means a more efficient brain, helping you to remember better.

The researchers presented their finding recently at the annual meeting of the American Association For The Advancement of Science in San Diego.