Scientists from the Swiss research group NeuroRestore have created a method that has allowed nine paralyzed people to walk again, ScienceAlert reports . All patients suffered from severe or complete paralysis due to spinal cord injury. Volunteers noticed improvements in their condition immediately after starting therapy and maintained the results achieved five months later.
Neuroscientists began an experiment with mice, identifying groups of nerves in them that can be stimulated by therapy. The nerve cells that control walking are located in the part of the spinal cord that runs through the lower back. Spinal cord injuries can interrupt the signal chain from the brain, preventing walking even when the lumbar neurons are still intact. Losing the ability to receive commands, these neurons responsible for walking stop functioning, which leads to paralysis of the legs.
Using RNA sequencing and spatial transcriptomics, a technique that allows us to study the activity of genes in specific tissues, researchers at the Swiss Federal Institute of Technology Lausanne have identified previously unknown neurons in the lumbar spinal cord that can fire after spinal injury. The tissue made up of these neurons does not appear to be required for healthy animals to walk, but is essential for recovery from injury. Neurons convert information from the brainstem into executive commands, which are then passed on to the neurons responsible for walking.
Neuroscientists have tested a technology called epidural electrical stimulation, which involves stimulation with a surgically implanted neurotransmitter. The patients also underwent intensive neurorehabilitation, which included a robotic support system. After five months of stimulation and rehabilitation four to five times a week, all nine volunteer patients were able to walk with the help of a walker.
At the same time, in recovered patients, a decrease in nerve activity in the lumbar spinal cord was observed during walking. This may be due to the fact that as a person improves in the performance of a task, the activity of the neurons responsible for this decreases. The study is published in the journal Nature.