A study conducted by the University of California at Berkeley has concluded that having a nap during the day makes you better at working things out.

The boffins gave 39 adults a difficult learning test in the morning then despatched half of them to go have a nap. A test was repeated after the nap and  those who were in the land of nod did better than the others who went down the pub.

Sir Winston ChurchillOne of the scientists, a Dr Matthew Walker of the Sleep and Neuroimaging Department at UC Berkeley, compared the effect to an inbox cluttered with heaps of emails in your hippocampus that becomes cleared after you have a nap.  That's an interesting comparison but as far we can tell has little evidence to back it up. The hippocampus, claims Dr Walker, is like an area of temporary storage.

Computers are responsible for all sorts of malefic effects including Powerpoint presentations and the tendency to spell long words with capital leTters in the middle. But to suggest that our brains are modelled on X64 technology and Microsoft Office is a metaphor too far.

The most famous example of a man who swore by his power naps was Winston Churchill, who managed to combine a fearsome appetite for brandy and cigars with a lengthy political career, each day dotted with the occasional power nap or three.