Max
05-02-2002, 11:17 AM
The many uses of cybernetic rats
Pentagon wants paralysis-research rodents trained as tiny soldiers
David Perlman, Chronicle Science Editor
Thursday, May 2, 2002
©2002 San Francisco Chronicle
URL: http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2002/05/02/MN47924.DTL
Medical researchers seeking ways to restore muscle control to paralyzed humans have implanted electrodes in the brains of laboratory rats and use them like remote-controlled robots.
As a result of the scientists' work, the Pentagon is now supporting the efforts to learn whether the rats, carrying tiny video cameras on their backs, might prove useful sniffing out hidden explosives, as mine detectors, or even to aid in search-and-rescue operations.
"It wasn't what our experiments started out for," said John K. Chapin, a neurophysiologist at the State University of New York's Downstate Medical Center. "We were really experimenting to see if we could use the rats as models to see if electrically stimulating the brains of patients with spinal cord injuries might let doctors teach them to move their arms or legs the way robots do."
In the scientific journal Nature today, Chapman and his colleagues report how they have implanted electrodes in the brains of five rats and trained them by transmitting electrical signals to their wired brains to follow directions, climb ladders and trees, run through tunnels and beneath rock piles, and even to move along brightly lit paths that dark-loving rats would normally shun.
Controlling the brain-body connection through stimulation with implanted electrodes isn't new; it was tried nearly 50 years ago in a series of famous and widely criticized experiments by the Yale neurophysiologist Jose Delgado, who thought he could treat epilepsy and schizophrenia that way. Nothing came of the work, except a best-selling science fiction novel by Michael Crichton called "Terminal Man."
Chapman's team has been experimenting with rats to see whether paralyzed human patients might one day be endowed with what he calls "robotic arms." Using implanted electrodes in the part of the brain that controls nerves and muscles of their arms, a patient might be trained to move a paralyzed arm by remote control signals.
When the group's experiments with rats showed success, the Pentagon's Defense Advanced Research Projects Agency began funding the work through its research program on Controlled Biological Systems. That program funds other researchers for a variety of projects including learning how geckos can climb walls with their adhesive feet and how bees and wasps might be trained to detect biological warfare agents.
Agency officials call Chapman's experiments one of several efforts at creating "hybrid brain-machine biosystems" that could operate in hostile or inaccessible environments.
Chapman's research has focused on the rats' sensitive whiskers, which the animals use to sense their surroundings. When a rat's whiskers on one side of its face touch anything, it normally turns in that direction.
So using a remote computer, the researchers trigger the implanted electrodes and stimulate each rat's brain just as if its whiskers had actually been touched on one side or the other. Then, each time a rat responds to the simulated whisker signal by turning correctly, another signal from the electrode "rewards" the rat by stimulating one of the pleasure centers in its brain.
In this way, Chapman explained, it's easy to train a rat using standard stimulus-and-reward methods to go anywhere, indoors or outdoors. In their experiments the researchers have controlled their rats' movements from more than 500 yards away, his team reports. Chapman's engineering colleagues have also developed a microminiaturized video camera that the rats carry in a backpack smaller than a sugar cube, but the camera needs to be improved because its image is still fuzzy when the rats are scurrying, he said.
"But just think how useful the animals could be searching for people in a collapsed building," Chapman said. "There's no robot that could scramble through difficult terrain and do that. But rats have 200 million years of evolution, and a robot rat can do it easily."
At Boston University, neurophysiologist Howard Eichenbach commented on Chapman's report, saying, "It may seem like he's just making the rats do circus tricks, but it's really a technical achievement and quite clever. Using a rat would certainly be a dirt-cheap way to find an enemy hidden in a cave, or sniff out a body in a ruin, and you could never get a million-dollar robot to do it. It's a challenging idea."
E-mail David Perlman at dperlman@sfchronicle.com.
Pentagon wants paralysis-research rodents trained as tiny soldiers
David Perlman, Chronicle Science Editor
Thursday, May 2, 2002
©2002 San Francisco Chronicle
URL: http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2002/05/02/MN47924.DTL
Medical researchers seeking ways to restore muscle control to paralyzed humans have implanted electrodes in the brains of laboratory rats and use them like remote-controlled robots.
As a result of the scientists' work, the Pentagon is now supporting the efforts to learn whether the rats, carrying tiny video cameras on their backs, might prove useful sniffing out hidden explosives, as mine detectors, or even to aid in search-and-rescue operations.
"It wasn't what our experiments started out for," said John K. Chapin, a neurophysiologist at the State University of New York's Downstate Medical Center. "We were really experimenting to see if we could use the rats as models to see if electrically stimulating the brains of patients with spinal cord injuries might let doctors teach them to move their arms or legs the way robots do."
In the scientific journal Nature today, Chapman and his colleagues report how they have implanted electrodes in the brains of five rats and trained them by transmitting electrical signals to their wired brains to follow directions, climb ladders and trees, run through tunnels and beneath rock piles, and even to move along brightly lit paths that dark-loving rats would normally shun.
Controlling the brain-body connection through stimulation with implanted electrodes isn't new; it was tried nearly 50 years ago in a series of famous and widely criticized experiments by the Yale neurophysiologist Jose Delgado, who thought he could treat epilepsy and schizophrenia that way. Nothing came of the work, except a best-selling science fiction novel by Michael Crichton called "Terminal Man."
Chapman's team has been experimenting with rats to see whether paralyzed human patients might one day be endowed with what he calls "robotic arms." Using implanted electrodes in the part of the brain that controls nerves and muscles of their arms, a patient might be trained to move a paralyzed arm by remote control signals.
When the group's experiments with rats showed success, the Pentagon's Defense Advanced Research Projects Agency began funding the work through its research program on Controlled Biological Systems. That program funds other researchers for a variety of projects including learning how geckos can climb walls with their adhesive feet and how bees and wasps might be trained to detect biological warfare agents.
Agency officials call Chapman's experiments one of several efforts at creating "hybrid brain-machine biosystems" that could operate in hostile or inaccessible environments.
Chapman's research has focused on the rats' sensitive whiskers, which the animals use to sense their surroundings. When a rat's whiskers on one side of its face touch anything, it normally turns in that direction.
So using a remote computer, the researchers trigger the implanted electrodes and stimulate each rat's brain just as if its whiskers had actually been touched on one side or the other. Then, each time a rat responds to the simulated whisker signal by turning correctly, another signal from the electrode "rewards" the rat by stimulating one of the pleasure centers in its brain.
In this way, Chapman explained, it's easy to train a rat using standard stimulus-and-reward methods to go anywhere, indoors or outdoors. In their experiments the researchers have controlled their rats' movements from more than 500 yards away, his team reports. Chapman's engineering colleagues have also developed a microminiaturized video camera that the rats carry in a backpack smaller than a sugar cube, but the camera needs to be improved because its image is still fuzzy when the rats are scurrying, he said.
"But just think how useful the animals could be searching for people in a collapsed building," Chapman said. "There's no robot that could scramble through difficult terrain and do that. But rats have 200 million years of evolution, and a robot rat can do it easily."
At Boston University, neurophysiologist Howard Eichenbach commented on Chapman's report, saying, "It may seem like he's just making the rats do circus tricks, but it's really a technical achievement and quite clever. Using a rat would certainly be a dirt-cheap way to find an enemy hidden in a cave, or sniff out a body in a ruin, and you could never get a million-dollar robot to do it. It's a challenging idea."
E-mail David Perlman at dperlman@sfchronicle.com.