By implanting electrodes in rats' brains, scientists have created remote-controlled rodents they can command to turn left or right, climb trees and navigate piles of rubble — and maybe someday, with the rats outfitted with tiny video cameras, use to search for disaster survivors.
"If you have a collapsed building and there are people under the rubble, there's no robot that exists now that would be capable of going down into such a difficult terrain and finding those people, but a rat would be able to do that," said John Chapin, a professor of physiology and pharmacology at the State University of New York in Brooklyn.
The lab animals aren't exactly robot rats. They had to be trained to carry out the commands.
Chapin's team fitted five rats with electrodes and power-pack backpacks. When signaled by a laptop computer, the electrodes stimulated the rodents' brains and cued them to scurry in the desired direction, then rewarded them by stimulating a pleasure center in the brain.
The rats' movements could be controlled up to 1,640 feet away, the length of more than five football fields.
The findings appear in Thursday's issue of the journal Nature.
Other researchers said the work is interesting but is an engineering feat, not an advance in animal neuroscience.
Randy Gallistel, a professor of psychology and cognitive science at Rutgers University, said it's basically the same thing, with a twist, that scientists found they could do almost 50 years ago by stimulating the reward-sensing area of a rat's brain.
"Without the gee-whizery, without the remote-control and so on, that this kind of thing was possible has been obvious for decades," he said.
The experiments used three implanted electrodes — one in the brain region that senses reward or pleasure, and one each in areas that process signals from the rat's left and right whisker bundles.
Chapin's team trained the rats in a maze by signaling the left and right whisker-sensing regions. When a rat turned in the correct direction, its reward-sensing region was stimulated.
Activating only the reward region caused the rodents to move forward, the team found.
After training, the rats were tested in a variety of environments and remotely guided through pipes and across elevated runways. They were compelled to climb trees and ladders and to jump from varying heights.
The rodents could even be commanded to venture into brightly lit, open areas — environments they normally would avoid.
Howard Eichenbaum, a professor of psychology at Boston University, said the research, while not a major advance, is "clever" and holds the promise of using animals as humans' "eyes" or as couriers to reach trapped victims.
Aside from the technological challenges, he said there may be ethical concerns about turning animals into "intelligent robots" serving humans.
"It's one thing to see a rat running around like this, people don't get too emotional about that, but as soon as you get into dogs or work animals, people start getting real excited," he said.
The potential of using such implantable electrodes to control humans — which a Tulane University researcher tried during the 1960s, with unclear results — is something Chapin said he opposes so strongly he believes it should be illegal.
Kate Rears, a policy analyst at the Electronic Privacy Information Center in Washington, said technological advances mean human-control technology can no longer be dismissed as far-fetched.
"I think that a lot of people are very wary of that sort of thing and understandably so," Rears said. "I don't think it's a sign of paranoia to react against this because it is very odd. It's Brave New Worldish."