  Parkinson's Disease (PD) is a progressive neurodegenerative movement disorder
that affects more that 6 million people worldwide. Motor dysfunction gradually
increases as the disease progress. It is usually mild in the early stages of
the disease but it relentlessly progresses to a severe or very severe
disability that is characterized by increasing degrees of bradykinesia,
hypokinesia, muscle rigidity, loss of postural reflexes and balance control as
well as freezing of gait. In addition to a line of treatment based on
dopaminergic PD-specific drugs, attending neurologists strongly recommend
regular exercise combined with physiotherapy. However, the routine of
traditional rehabilitation often create boredom and loss of interest.
Opportunities to liven up a daily exercise schedule may well take the form of
character-based virtual reality games which engage the player to physically
train in a non-linear and looser fashion, providing an experience that varies
from one game loop the next. Such "exergames", a word that results from the
amalgamation of the words "exercise" and "game" challenge patients into
performing movements of varying complexity in a playful and immersive virtual
environment. In fact, today's game consoles using controllers like Nintendo's
Wii, Sony PlayStation Eye and the Microsoft Kinect sensor present new
opportunities to infuse motivation and variety to an otherwise mundane
physiotherapy routine. But are these controllers and the games built for them
appropriate for PD patients? In this paper we present some of these approaches
and discuss their suitability for these patients mainly on the basis of demands
made on balance, agility and gesture precision.
