How much effort goes into picking up a spoon? The planning and anticipation of which hand to use, where to place the hand, when to open and close the fingers, and how much weight to anticipate is complex and requires much coordination of the nervous and musculoskeletal systems.
In a normally functioning nervous system, movement of the extremities occurs when electrical impulses from the brain trigger a response which is sent to muscles. The central nervous system (brain and spinal cord) passes along electrical signals to the peripheral nervous system, and the nerves in the peripheral nervous system respond by communicating with their corresponding muscles.
When a person has a neurological injury causing paralysis, the signals between the central nervous system and peripheral nervous system are interrupted. Suddenly, simple every day tasks become complicated. An injury such as a fall causing quadriplegia can leave a person struggling to figure out how to move around and perform previously effortless everyday tasks such as eating and getting dressed. The aspiration with medical technology, then, is to make the transition from injury to adjustment as smooth as possible.
Neuroprosthetics are medical devices intended to assist with injuries to the nervous system. In recent years, there has been much growth with this technology using brain-computer interface (BCI), robotics, and exoskeleton technology. The challenge with neurological injuries, however, is that it is very difficult to replicate the intricate and precise workings of the brain and nervous system.
The team from BrainGate recently published a study following a quadriplegic subject in which they ultimately allowed him to use his brain to successfully control the movement in his arms to be able to feed himself. This amazing coordination of technology was achieved by implanting electrodes into his brain which picked up electrical signals and transfer these signals to Functional Electrical Stimulation (FES).
In this study, the electrodes implanted in the motor cortex picked up the electrical signals as he planned to use his upper extremities. The BrainGate system is able to decipher the signals from the brain activity and transfer it to the FES system through electrical pulses. These electrical pulses stimulated the muscles in his arm, creating the desired movement which the participant had planned for. Specifically, the man was able to feed himself using his hand for the first time in 8 years.
Still an investigational device, the BrainGate system is so promising in providing independence and versatility of movement, and the team is now working with the Harvard Wyss Center. The hope is that someday individuals will be able to implement neurotechnology such as this as soon as possible after injury, allowing for adjustment before the deleterious effects of immobility set in.
Watch the video below for more insight into this amazing work: