The Bionic Rat
From: Discover Magazine - November, 1999 - Page 27

In his Philadelphia lab, neurologist John Chapin has connected a robotic arm
to the brain of a rat, creating a direct link between mind and machine. 

Chapin and his colleagues at the MCP Hahnemann School of Medicine began
teaching rats to press a lever that moved a robotic arm holding a tiny cup of
sweetened water. Electrodes implanted in the rats' brain recorded which
neurons they used and converted the signals into an electrical impulse that
could directly control the motorized arm. Soon the rats no longer needed to
press on the bar to get their sugary treat; they just had to think about it. 

A much-refined version of this system could begin aiding paralyzed humans in
about a decade, Chapin says. He forsees placing about 500 mini-electrodes in
the brain, along with miniatured detectors that would pick up, amplify, and
transmit neural signals. Those signals would allow the patient to move either
a robotic arm or a powered exoskeleton built around the real arm. Eventually
it might be possible to route nerve impulses from the brain to another set of
electrodes that would stimulate muscles in the paralyzed limb, restoring the
lost mobility. 

"The hardest thing to do will be to produce gait and posture, since it is
such a complex process, but I think it could be done," Chapin says. 

http://207.103.26.64/~rybak/chapin.html
