Perceptual Motor Calibration in Patients with Parkinson's Disease

Parkinson's disease (PD), one of the most pervasive degenerative disorders associated with
ageing, affects roughly 50 million people worldRwide [1]. Although the cause of PD is largely
unknown, PD is characterised by behavioral deficits in the motor system, specifically,
postural instability, slowness in movement, rigidity and tremors [2]. These motor deficits
are thought to arise from specific dopaminergic cell death in the basal ganglia, an area of
the brain associated with action selection and regulation.
Although commonly considered a disease associated with motor execution, the
involvement of the basal ganglia suggests that PD may also involve a failure in the ability to
use perceptual information to anticipate and update our perceptions of our action
capabilities. Indeed, the basal ganglia provides extensive links between areas implicated in
visual, somatosensory and motor processing [3]. This intermodal processing is essential,
because our body and its abilities are dynamic, and we must constantly update our
perceived capabilities following physiological and/or morphological changes in our bodies.
This updating has been coined "perceptual motor calibration".