Networked rats controlled with brain implants could soon be used to find earthquake survivors buried under rubble.

Scientists at the State University of New York have been steering five 'Clockwork Orange' rodents by remote control using wireless networking technology.

Electrodes were implanted into areas of the rats' brains responsible for sensing reward as well as those that process signals from their whiskers.

The university's Dr Sanjiv Talwar explained that the commands were transmitted by radio from a laptop computer to a backpack receiver strapped to each rat.

"Our rats were easily guided through pipes and across elevated runways and ledges, and could be instructed to climb, or jump from, any surface that offered sufficient purchase," he said.

"We were also able to guide rats in systematically exploring large, collapsed piles of concrete rubble and to direct them through environments that they would normally avoid, such as brightly lit open areas."

If the rat followed a cue and turned in the correct direction, its reward centre was stimulated, giving the rat a feeling of pleasure.

"Rats have native intelligence which is a lot better than artificial intelligence," said Dr Talwar. "It is a hard problem simply trying to make a robot move properly over unpredictable terrain.

"It would be a simple matter to train rescue rats to recognise and home in on the smell of a human trapped under rubble."

The doctor acknowledged that there might be ethical objections to such an idea, even if it could save human lives, but insisted that the rats were "treated well".

"Our animals were completely happy and in no sense was there any cruelty involved," he said.