Nineteen years ago, a patient with paralysis managed to move a cursor on a computer screen with the help of a probe implanted in his brain. Technological development has been exponential over the last decade and the computer cursor movement has evolved into “thought-induced” movement of robotic arms. The technology consists of implants and brain probes that are connected to different machines, including robotic arms. Robotic arms are used to help people like Jan Scheuermann, a woman suffering from a neurodegenerative disease, paralyzed since 2003.
Jan Scheuermann with her robotic arm
Bypassing Paralysis with thought
Researchers like Grégoire Courtine of the École polytechnique fédérale de Lausanne have pushed the boundaries of science. The technology that allows objects to be moved with “thought” is intended to reverse paralysis. Probes and brain implants are no longer connected to robotic arms, but are placed inside the body of the paralyzed patient. This principle is known by researchers as a “neural bypass”.
How does this new technology work? Two implants smaller than a postal stamp are placed in the brain. The implants are connected to hundreds of hair-sized probes that can detect neural commands. The neural bypass is achieved by adding an implant to the spinal cord. Neural commands are produced when the patient transmits the intention to perform a movement. These commands are detected by the probes and transformed into electrical signals to the spinal cord implant, as shown in the following video.
Researchers Robert Kirsch of the Case Western Reserve University and Bolu Ajiboye of the Cleveland Functional Electrical Stimulation Center, performed the neural bypass by adding electrodes to the arm muscles of Bill Kochevar, who became quadriplegic after a bicycle accident, almost 10 years ago. Thanks to the implants and electrodes, Bill manages to move his arm by himself, as presented in the following video.
This type of technology is still in its infancy, but shows great promise in improving the quality of life of people paralyzed as a result of accidents or neurodegenerative diseases. It is even listed as one of MIT‘s 10 Breakthrough Technologies for 2017.
The reference article can be found here.
Caroline Lecours is a PhD student in the Mechanical Engineering Department at ÉTS. The objective of her PhD project is to determine concussion risks and frequency in soccer practice.
Program : Mechanical Engineering