An electronic chip implanted in the brain may help establish new nerve connections in the part that controls movement, suggests research from the University of Washington.

A study, to be published in the November edition of the journal Nature, found such a device can induce brain changes that may result in the rehabilitation of patients with brain injuries, stroke or paralysis.

When awake, the part of the brain called the motor cortex governs the body's voluntary movements. It sends signals down to the spinal cord to control the contraction of certain muscles, such as in the arms and legs.

Researchers attached a special computer chip called the Neurochip to the top of monkeys' heads to record the brain's motor cortex nerve signals.

The Neurochip creates a brain-computer interface that records every movement sent from the motor cortex to the rest of the animal's body. 

The device then changes those signals into a stimulus that can be transmitted back to the brain, creating a new artificial connection that could be used if the motor cortex was damaged in some way.

Researchers said that a likely cause of these changes was the strengthening of pathways within the cortex from the recording to the stimulation site, which might have been produced by the continuous synchronization of activity at the two sites, created by the Neurochip.

Dr. Eberhard Fetz, professor of physiology and biophysics and co-author of the study, said that brain changes are produced in a day of continuous conditioning with the repetitive brain-computer interface, but last for many days after the circuit is turned off.

"This unusually long-lasting plasticity may be related to the fact that the conditioning is associated with normal behavior," he said.

The research was funded by the National Institutes of Health, the Office of Naval Research, and the University of Washington Royalty Fund.