Risk Factors Suggest Preclinical Parkinson's : Look for excessive daytime sleepiness, olfactory dysfunction, constipation, and slow reaction time.

▸ Reaction time. PD patients have a prolonged reaction time, which reflects the akinesia and bradykinesia of the disease. Dr. Ross and his colleagues also have determined that there is prolonged reaction time with the presence of incidental Lewy bodies. Reaction time was assessed for the HAAS cohort using a computerized reaction time test (the 3RT).