Premotor Parkinson's disease: concepts and definitions.

Parkinson's disease (PD) has a prodromal phase during which nonmotor clinical features as well as physiological abnormalities may be present. These premotor markers could be used to screen for PD before motor abnormalities are present. The technology to identify PD before it reaches symptomatic Braak Stage 3 (substantia nigra compacta [SNc] involvement… CONTINUE READING