INTRODUCTION
Parkinson’s disease (PD) is a progressive neurological
condition affecting up to 10 million people worldwide,
with onset generally in those over 50 [9]. PD manifests
itself in motor symptoms including rigidity, tremor and
bradykinesia, or slowness of movement [2]. These affect
balance, gait, arm and facial movements. Motor blocks
(freezing) most commonly affect an individual’s legs
during walking and is generally referred to as freezing of
gait. Speech and voice are also typically affected in terms
of volume and clarity. People with PD can also be prone to
transient and unpredictable “ON/OFF” cycles, wherein
medication becomes less effective at treating symptoms,
giving periods of effectively controlled symptoms (ON)
and periods of severe symptoms (OFF). Aside from the
physical signs of PD there are a myriad of emotional and