Firstly, the mechanism underlying speech and language impairments in Parkinson’s disease has always been a research hotspot Keywords such as “dementia,” “Alzheimer’s disease,” “basal ganglia,” “subthalamic nucleus,” “levodopa,” “progressive supranuclear palsy,” and “alpha-synuclein” indicate the effort in mechanism research. This evidence concerns the gene SNCA and early-onset autosomal dominant Alzheimer disease.