TAPPING
INTO YOUR BRAIN
Good and Evil Potentials You will realize
that this development has great potential for good and evil. Quadriplegics
may one day at least be able to feed themselves easily and do many normal functions
which can be accomplished with robots. But, this opens a field of human
manipulation, for what can be done by the brain can be done TO the brain as well.
Think on this one.
Rats use thoughts to control robots
Neuron-monitoring technique could someday aid humans WASHINGTON, June
23 , 1999— It sounds like something out of science fiction — a rat with
a small electrode sticking out of its head decides it wants a drink and, without
touching anything at all, gets a robotic arm to bring it some water. Still, a
team of neurobiologists say their rats can control a machine with brainpower alone,
and they think their technology may someday help paralyzed people.
The New Brain “THE PEOPLE in the lab started calling
the experiment the ‘thinking about drinking experiment,’” John
Chapin of Hahnemann Medical College in Philadelphia, who led the research, said
in a telephone interview. “But we don’t know whether rats think.”
Whatever the rats are doing, they are controlling the robotic arm without touching
anything, said Chapin, who worked with colleagues at Duke University in North
Carolina. Reporting in the July issue of the journal Nature Neuroscience, they
said they implanted tiny electrodes, no thicker than a hair, into the brains of
six rats. “It doesn’t hurt the animal,” Chapin said. “All
there is is a little plug coming out of the animal’s head. He runs around
the cage and everything.” The electrode is recording the activity of neurons
— on average, 46 — which Chapin found was important to making the experiment
work. Earlier studies that recorded the activity of just one or a
few brain cells did not work. “We trained the rat initially to put his paw
on a lever and to press the lever down. When the lever got pressed down, there
was a robot arm that moved over to a water dropper and then brought the water
back to the animal’s mouth,” Chapin said. The rats had to control the
lever carefully: If they only pushed the lever halfway, it would only bring the
arm halfway to them. BRAIN ACTIVITY RECORDED Chapin’s
team then recorded the brain activity associated with the movement of pressing
the lever. “We have an electronic device that converted those patterns of
activity in the brain of the animal into a single electronic signal that could
move the robot arm,” Chapin said. Soon they disconnected the lever
from the robot arm and hooked it up to the converting device alone. They found,
as other researchers have, that the brain activity controlling the movement came
before the actual movement. “When control of the robot arm was switched to
the brain, the robot arm went over and brought water to the animal’s mouth
before the animal even started to move,” Chapin said. “After a couple
of days, the animals began to recognize that, and they stopped actually pressing
the lever.” HUMAN TESTS? Chapin said if
the technique can be proven safe and reliable in animals such as monkeys, which
have bigger and more complex brains than rats, it might eventually be tested in
people with severe paralysis. “If this really becomes a workable thing, I
think there are a lot of people that could use it,” he said. It is important
to record the signals from many neurons and not just a few, Chapin said. Of the
six rats tested, he added, just four could get the arm to work. “Two rats
would do it a few times, and then they would stop,” he said. “The reason
was, we were not recording enough neurons in those animals. The robot
arm would jerk around a lot and it wasn’t smooth. When the animal tried to
get his mouth around it, it would kind of bop him on the nose. They didn’t
like it.” For complex movements, such as those made by an artificial limb,
even more neurons will be required, he said. “In principle, it should be
possible to tap this information and control a prosthetic limb,” Eberhard
Fetz of the University of Washington in Seattle wrote in a commentary on the findings.
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