Research are finding that rerouting nerve signals in primates may be surprisingly easy
DailyTech previously covered how monkeys had been wired with brain probes to a mechanical arm, which they learned to control. Now another experiment has taken such concepts, much farther, reversing paralysis in monkeys through neuron implantation.
Eberhard Fetz, a professor of physiology and biophysics at the University of Washington, led the research. The researchers began by paralyzing the nerves leading to the monkeys’ arms. They then placed a single wire on a neuron in the monkeys’ neural cortexes. From there they routed the signal to a single neuron implanted in the monkeys’ arm muscles. The computer detected a specific firing pattern in the brain neuron and would then signal the neuron in the arm.
The electric “re-routing” working surprisingly well and the monkeys regained control of their wrists. Their new capability was assessed by a simple video game. The game was controlled by the monkeys’ wrist motions. By moving their wrists, they could move a cursor onscreen and by moving it to a box on the side, they could earn a reward. With the incentive of the reward the monkeys soon learned to move their wrists, even though the motor cortex neuron was selected at random.
Chet Moritz, a senior research fellow at the University of Washington and coauthor of the researchers’ paper states, “We found, remarkably, that nearly every neuron that we tested in the brain could be used to control this type of stimulation. Even neurons which were unrelated to the movement of the wrist before the nerve block could be brought under control and co-opted.”