Parkinson’s Disease is a progressive degeneration of the central nervous system characterised by resting tremor, slowness of movement, stiffness in the arms and legs and flexed posture.  The prevalence of Parkinson's Disease is estimated to be 0.5-1% of people aged 50 years and above.

Dementias include a variety of common conditions that share a common symptom presentation characterised by the development of multiple cognitive defects but are differentiated based on the cause of the disease. One example of a dementia is Alzheimer’s disease.