The discovery that an unexpected brain region is crucial for walking recovery in mice with spinal cord injuries has led a deep brain stimulation therapy in humans. The approach restored enough leg control in two individuals with partial spinal injuries to walk unaided and even climb stairs.
Idk what brain region it was in, but I once drove a guy who had some sort of brain stimulation for Parkinson’s. Had this match-box sized box of batteries for it in his chest. (Batteries were shit like 15 years ago.) He was hyped about it, and I’m sure whatever he had was pretty rudimentary by today’s standards.