ABSTRACT
INTRODUCTION The current medical management is only partially effective in controlling the symptoms and signs of Parkinson’s disease (PD). Particularly the motor and nonmotor impairments that occur late in the course of the disease, such as freezing or dementia, respond poorly to medication, and may even be caused by medication (1). Moreover, the current medical management mainly targets dopaminergic impairments and is therefore not effective for impairments that are largely related to nondopaminergic lesions in PD, such as impaired balance (2). Consequently, even patients with optimal medical management face mounting and varied problems in daily functioning (3,4).
