Many post stroke patients end up with an upper extremity that doesn’t cooperate, requiring the brain to relearn how to use it. This can be a difficult process often requiring a lot of mental stamina, so there’s a lot of efforts underway to help improve the speed and quality of recovery. At Washington University in St. Louis researchers have developed and tested a stroke rehabilitation system that reads brainwaves and in turn controls a robotic device attached to the affected arm.
The patient wears an electroencephalography (EEG) cap, which is connected to a computer capable of identifying when the patient is trying to move the arm. These signals are translated and sent to a robotic brace worn over the forearm, wrist, and fingers. As an intention is translated, the brace immediately moves to follow along with the patient’s wishes.
This process is repeated over and over, and in a study of chronic stroke patients who have essentially stopped improving, the system was able to help restore some arm movement.
The system is actually partially based on a recent realization that a small area on the same side of the brain is actually involved in moving an arm. This area is actually activated before the larger area on the opposite side of the brain that for long was thought as completely responsible for movement. Since the opposite side of the brain from the affected arm is what was damaged by a stroke, the above mentioned region on the same side of the brain is not affected and can be used as a trigger to identify when the person wants to move the disabled arm.