Special electrodes implanted in the brain and muscles show potential for someday helping people paralyzed by spinal cord injuries to regain some fine motor skills, according to a report recently published in the scientific journal Nature.
The study, performed by a research team with Northwestern University in Chicago and funded in part by the National Institutes of Health, involved lab monkeys whose arms were temporarily “paralyzed” through the use of a local anesthesia. The scientists implanted special electrode devices into the monkeys’ brains and arms; after the animals’ arms were anesthetized, the electrodes were activated and the monkeys were tasked with picking up a ball. Although their functioning wasn’t perfect, the monkeys were able to perform the task, showing that the implants allowed the brain to communicate directly to the muscle without using the spinal cord.
The research team is hopeful that this direct brain-to-muscle communication technology might someday help humans with spinal cord injuries, although human trials are approximately five years away. The study’s authors were also careful to point out that the results might not be as positive in spinal cord injury patients because they typically suffer muscle atrophy in their paralyzed limbs, compared to the well-developed muscles in the test monkeys’ arms.
Some similar electric stimulation devices are already in use. For example, devices are currently used to help control “foot drop,” a condition that causes patients’ feet to catch on the ground, increasing their risk of tripping and falling. Another device allows some patients to open and close their hands by shrugging their shoulders. However, to date no device has been developed to give spinal cord injury victims the ability to perform more complex movements. Researchers hope to eventually make such mobility possible.