A quadriplegic woman has made medical history by using a robot arm with just her thoughts to pick up big and small boxes, a ball, an oddly shaped rock, and fat and skinny tubes.
According to the researchers at the University Of Pittsburg School Of Medicine, this is the first time a participant has used -degree brain control of a prosthetic device to reach, grasp, and place a variety of objects.
Senior investigator Jennifer Collinger, Ph.D., assistant professor, Department of Physical Medicine and Rehabilitation (PMandR), Pitt School of Medicine, and research scientist for the VA Pittsburgh Healthcare System, said that their project has shown that they can interpret signals from neurons with a simple computer algorithm to generate sophisticated, fluid movements that allow the user to interact with the environment.
In February 2012, small electrode grids with 96 tiny contact points each were surgically implanted in the regions of trial participant Jan Scheuermann's brain that would normally control her right arm and hand movement.
Each electrode point picked up signals from an individual neuron, which were then relayed to a computer to identify the firing patterns associated with particular observed or imagined movements, such as raising or lowering the arm, or turning the wrist. That "mind-reading" was used to direct the movements of a prosthetic arm developed by Johns Hopkins Applied Physics Laboratory.
Within a week of the surgery, Ms. Scheuermann could reach in and out, left and right, and up and down with the arm to achieve 3D control, and before three months had passed, she also could flex the wrist back and forth, move it from side to side and rotate it clockwise and counter-clockwise, as well as grip objects, adding up to 7D control.
To bring the total of arm and hand movements to 10, the simple pincer grip was replaced by four hand shapes: finger abduction, in which the fingers are spread out; scoop, in which the last fingers curl in; thumb opposition, in which the thumb moves outward from the palm; and a pinch of the thumb, index and middle fingers.
The study was published online in the Journal of Neural Engineering.