Parkinson Disease (Parkinson's Disease) By Hector A Gonzalez-Usigli, MD, HE UMAE Centro Médico Nacional de Occidente Reviewed / Revised Feb 2022 | Modified Sep 2022 View Patient Education Pathophysiology Etiology Symptoms and Signs Diagnosis Treatment Key Points Topic Resources Basal Ganglia: Coronal Section Basal Ganglia: Regional Dissectio... Basal ganglia Some Commonly Used Oral Antiparki... Parkinson disease is a slowly progressive, degenerative disorder characterized by resting tremor, stiffness (rigidity), slow and decreased movement (bradykinesia), and eventually gait and / or postural instability.