|
I, Ratbot
Copyright 2002 by Edward Willett
Picture this: there's been an earthquake and you're trapped in the rubble. In the dark you hear a scrabbling sound...and
feel the long, naked tail of a rat slither across your cheek...
Sounds like a nightmare, doesn't it? But if recent
research bears fruit, it may be a dream come true--because that rat could be a remote-controlled rescue rat.
Last
week's issue of Nature contained details of experiments carried out at the State University of New York and Drexel University
in Philadelphia in which, by surgically implanting three electrical probes into the brains of rats, researchers were able
to remotely control the rat's actions from up to 500 metres away.
Researchers have been experimenting with electronic
animal control for decades. In the 1960s, Jose Delgado, a Yale physiologist, wired an electrode into the brain of a bull.
As the bull charged him, he flicked a switch on a transmitter--and the bull stopped, turned, and walked quietly away.
In
the same decade, the CIA spent $14 million developing Acoustic Kitty, a cat with a microphone surgically implanted in its
gut and a navigating antenna in its tail. Alas, Acoustic Kitty was run over and killed during its first test mission.
More
recent experiments have included a two-wheeled robot operated partly on the electrical signals from the displaced brain of
a lamprey, robotic arms controlled solely by brain signals from rats and monkeys, and a cockroach fitted with a micro-robotic
backpack to control its movements, developed at Tokyo University.
In the remote-controlled rat experiment, each of
five rats was fitted with two probes to its brain that triggered sensations similar to what the rat would feel if something
touched its right or left whiskers. The third probe went to the medial forebrain bundle, or MFB, which, when stimulated, sends
the rat a feeling reward. The probes ran to a backpack on the rat's back, which contained an antenna and a remote-controlled
stimulator.
The rats were first trained in a maze. When the left-whisker or right-whisker probe
was stimulated, and the rats turned in that direction, they were rewarded with a pulse to the MFB. Applying a pulse to the
MFB alone, the researchers found, caused the rats to continue moving forward. Essentially, they were trained the way rats
have always been trained, except the reward was direct stimulation of the brain instead of food.
Once the rats were
taken out of the maze, they continued to obey the turn-left, turn-right commands, issued from a laptop computer using either
key commands or a joystick. Researchers were able to guide the rats up ladders, down stairs and across narrow ledges; even
up and down trees, though the rats had never been outside before.
|
 |
|
Funding came from the U.S. Department of Defence, and was partly inspired by search-and-rescue efforts after
the September 11 terrorist attacks. Robots are sometimes used in search-and-rescue efforts, but no robot can traverse difficult
terrain as well as a rat or penetrate the tiny spaces rats can penetrate. Equipped with tiny video cameras, remote-controlled
rats could become valuable tools for finding trapped people.
There are problems to be resolved. Cameras attached to
the test rats returned video too jerky to be of much use. Another problem would be knowing when the rats found something.
You'd also have to be able to pinpoint the rat's location. Loss of signal could be a problem, too, although it might be possible
to create a wireless computer network to ferry data among a pack of rats, so that if one rat were out of direct contact with
its operator, its signal could be picked up and relayed by other rats.
There are also ethical concerns. Animal rights
activists feel the process is demeaning to animals. Others worry about the same process being applied to people. The scientists
who conducted the experiments reject human experiments, but they insist the rats were treated very well and seemed to enjoy
what they were doing.
The biggest problem may simply be the fact that you're dealing with rats. They could easily
be distracted by blood or other remains in rubble, and neither rescuers nor victims are likely to enjoy the sight of rats
scurrying around. But over time, says Dr. John K. Chapin of the State University of New York, one of the researchers, people
might actually learn to like rats. "Maybe if it becomes widely known there are these rescue rats," he suggests, "people wouldn't
be scared."
I guess we'll just have to wait and see...preferably not alone in the dark.
These weekly columns
on science appear in the Regina (Saskatchewan) Leader Post and Red Deer (Alberta) Advocate and on CBC Radio One's Afternoon
Edition in Saskatchewan.. They are available for one-time publication or regular syndication to any interested newspapers,
magazines or on-line publications. E-mail me for details.
|
|
|
