PITTSBURGH -- Scientists at the University of Pittsburgh Medical School make a big breakthrough that could eventually help people with paralysis and spinal cord injuries.

A monkey successfully fed itself with a human-like robotic arm by using only signals from its brain.

The study was published in the journal Nature.

Andrew Schwartz, senior author and professor of neurobiology at the University of Pittsburgh School of Medicine, said, “Our immediate goal is to make a prosthetic device for people with total paralysis. Ultimately, our goal is to better understand brain complexity.”

Previous work focused on using brain-machine interfaces to control cursor movements displayed on a computer screen.

Monkeys in the Schwartz lab have been trained to command cursor movements with the power of their thoughts.

Using this technology, monkeys in the Schwartz lab were able to move a robotic arm to feed themselves marshmallows and chunks of fruit while their own arms were restrained.

Computer software interprets signals picked up by probes the width of a human hair. The probes are inserted into neuronal pathways in the monkey’s motor cortex, a brain region where voluntary movement originates as electrical impulses.

The neurons’ collective activity is then evaluated using a computer and then sent to the arm, which carries out the actions the monkey intended to perform with its own limb.

Movements are fluid and natural, and researchers said evidence shows that the monkeys come to regard the robotic device as part of their own bodies.

“The monkey learns by first observing the movement, which activates his brain cells as if he were doing it. It’s a lot like sports training, where trainers have athletes first imagine that they are performing the movements they desire,” Schwartz said.

The study was funded by the National Institute of Neurological Disorders and Stroke at the National Institutes of Health.

To watch more video of the monkey in Schwartz Lab University of Pittsburgh