Nov. 2, 2006 — An implantable brain chip that serves as an artificial connection between nerve cells could one day help rehabilitate lost muscle movement in patients who have suffered brain injuries, stroke or paralysis.
"We found that when we put in these connections for long periods of time, we induce a reorganization of wiring in the brain," said Andrew Jackson, a senior research fellow in physiology and biophysics at the University of Washington in Seattle.
Jackson and his team reported their findings on the so-called Neurochip in a recent issue of the journal Nature.
Reorganizing the brain's wiring can be a long and frustrating process for people who have lost muscle use after an injury or stroke.
Typically, they must spend many hours doing physical exercises that encourage brain signals to find new pathways through healthy tissue.
But those new pathways are not always complete, which can translate into limited recovery of movement.
Or a given pathway may never form at all, which means the person has to find a completely new way to perform a task.
The Neurochip is designed to encourage the brain to build those pathways by stimulating nerve cells.
For the experiment, the scientists first mapped the brain activity of a healthy monkey and located two sites in the animal's motor cortex; one site made its hand move to the left and the other made its hand move to the right.
Next, the researchers attached a Neurochip to each site. About 6 centimeters in diameter, the chip contains two circuit boards and a battery, operating without wires to allow the monkeys to move freely.
"This neural chip was completely self-contained," said Andrew Schwartz, a professor of neurobiology at the University of Pittsburgh.
