Rats may soon overtake dogs in the "man's best friend" league table, helping in search and rescue missions and landmine detection. Their new status becomes possible following the development of brain probes which allow rat movements to be guided by a remote human operator.
The new "ratbots" were developed by a team at the State University of New York and are featured this morning in the journal Nature.
"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 (such as trees)," the researchers say.
Laboratory rats have long been taught to navigate mazes after being rewarded with food. The team has short-circuited all this effort however by developing electrical probes that stimulate various parts of the rat brain, most importantly its "reward centre".
The rats were kitted out with little backpacks carrying radio-controlled microchips which could deliver tiny electrical impulses to the brain.
One connected to the reward centre and two others to brain areas responding to their right- and left-side whiskers.
The researchers first trained the rats to move forward and turn left or right on the basis of the brain stimulation and the reward centre was triggered when they got it right.
The rats took to it like a shot "running forwards and turning instantaneously on cue".
The accompanying diagram shows one of the more complicated routes, which brought the rat up a ladder, across a narrow ledge, down a flight of steps, through a hoop and then down a steep ramp.
The researchers believe ratbots kitted out "with electronic sensing and navigation technology" could perform life-saving roles "such as search and rescue in areas of urban destruction and landmine detection".
