What are the symptoms of Parkinson’s disease? What are the possible causes?

Parkinson’s disease (PD) is a progressive neurological condition that affects movement and behavior. It is the second most common neurodegenerative disorder after Alzheimer’s Disease, affecting approximately 10 million people worldwide (Bankhead, 2020). Its cause remains unknown; however, many factors have been identified as contributing to its development. The main symptoms of PD include tremor or shaking movements of the hands, arms, legs, jaw and face; stiffness or rigidity of the limbs and trunk; slowness of movement (bradykinesia); balance problems (postural instability); loss of automatic movements such as blinking or smiling; problems with speech or swallowing; depression/anxiety and changes in thought processes.