Brain Machine Interface Video
Trauma to the spinal cord causes a disruption in the pathways connecting the brain to the muscles, resulting in muscle weakness and paralysis. When an injury occurs in the cervical levels of the spinal cord, the muscles of the hands may become paralyzed. Finger movements (C8/T1 levels) are important, but grasping function can be somewhat compensated for by wrist extension (C6 level). However, for people with C5 motor function or above, the loss of hand function results in an inability to perform many activities of daily living, which in turn leads to dependence on caregivers and family. When asked to identify the function that would most dramatically improve their life, about half of people with cervical-level SCI ranked arm/hand function as their highest priority. Restoration of hand function would offer those with high-level SCIs an increased level of independence and greatly improved quality of life.
Researchers at The Miami Project to Cure Paralysis and the Department of Biomedical Engineering have been working on strategies to give people control over their paralyzed hand muscles. Electrodes that deliver electrical stimulation were placed over paralyzed muscles, and a cap that records electrical activity from the brain was placed on the research subject’s head. Subjects were asked to imagine opening and closing their hand, which modulated the electrical activity in their brain. Those electrical signals were then sent to a computer, where relevant features were extracted and sophisticated algorithms decoded them in real time. Based on that decoding, the computer then sent electrical stimulation that either opened or closed the hand. People with motor complete, cervical SCI were able to control their hand muscles via a brain-computer interface with minimal training.