Presence Hallucination in Parkinson's Disease

Inclusion Criteria: * Diagnosed with Parkinson's disease * Able to understand instructions and provide informed consent. * Native speaking language of experimental site (or acquisition of language of experimental site before 6 years old). * Montreal Cognitive Assessment (Nasreddine \& Patel, 2016) with score ≥ 22. * Able to manipulate the robotic device. Exclusion Criteria: * Neurological comorbidities other than Parkinson's disease (e.g. Alzheimer's disease, vascular dementia, multiple sclerosis, stroke, traumatic brain injury, epilepsy, chronic migraine, etc.) * History or current condition of substance abuse and/or dependence (e.g., alcohol, drugs). * Suffering from or diagnosed with psychiatric illnesses according to DSM-V criteria (e.g., schizophrenia, bipolar disorders, autism, personality disorders, phobia etc.). * Family history (1st and 2nd degree) of psychiatric disorders (e.g., schizophrenia or bipolar disorders). * Severe somatic illnesses (e.g., cancer). * Severe tremors or physical disability preventing optimal use of robotic device. * Participating in a pharmacological study. * Local or general anaesthesia 30 days prior experiment * Inability to provide informed consent (legal guardianship) * The following are due to the MRI scanner: body weight exceeding 160kg, implanted metallic devices, foreign metallic objects, unstable angina, cardio-vascular diseases, tattoos with metallic components, external metallic objects, claustrophobia, pregnancy.