Sleeping in mid-shift boosts busy workers

Sleeping on the job helps to boost mental performance by preventing the brain becoming overloaded by too much information, a new study suggests.

Without a "power nap", too much data can flood the brain of a busy employee, "frying" the neurons and leading to a loss of learning ability. Naps lasting an hour or less had previously been shown to improve alertness, productivity and mood.

Scientists at Harvard University in Cambridge, Massachusetts, who reported their findings in the journal Nature Neuroscience yesterday, found that sleep, and not merely resting with the eyes closed, was necessary to produce the restorative effect.

The scientists, led by Sara Mednick, wrote: "It suggests that the psychological sensation of 'burn out', described anecdotally as increased irritation and frustration along with decreased effectiveness after prolonged cognitive effort, may not reflect a general mental fatigue, but rather the specific need of an overused local neural network to enjoy the restorative benefits of sleep."