Mind Muscle Connection

I was debating whether to ask CT this or not (feel free to move it to Injuries and Rehab forum), but the topic comes up often and fascinates me.

A good friend of mine always complains about only feeling the mind muscle connection on only 1 side of his body for all muscle groups. He is about 26 years old, in good shape, but had suffered a stroke more than a few years ago and told me it partially gave him a British accent out of nowhere. There is nothing physically wrong with him, other than developing mild scoliosis.

I always joke that he should be on “Stan Lee’s Superhumans” show, but is there anything this young man can do to get the other side to connect? No matter how much weight he uses, he says he feels nothing.