 from Parkinson's dementia, which I hadn't heard of, but people that know it are familiar with it, says the signs are unmistakable. His shuffling gait, the absence of associated movements like facial expression, arm swinging. When he does swing his arms, it appears stilted, probably because his handlers have told him to swing his arms when he walks. It's something we all do naturally, but it goes away in Parkinson's disease.