US scientists say sleeping on the job should possibly be regarded as good conduct rather than slacking. The research shows that napping for 30 minutes or an hour during the day maintains mental performance when the brain is overloaded.

Without a "powernap" too much information flooding the brain of a busy employee can "fry" the neurons and lead to a loss of learning ability.

Daytime naps lasting an hour or less have previously been shown to improve alertness, productivity and mood, especially under sleep-deprived conditions such as those experienced by night-shift workers.

But it is not clear what effect napping has on the brain and whether it has an impact on learning.

The scientists, writing in the journal Nature Neuroscience, found that deep, slow-wave sleep was important for enhancing performance. Different versions of the experiment indicated that sleep, and not merely resting with the eyes closed, was necessary to produce the restorative effect. - (Ananova.com)