Parkinson's Disease (PD) is a nationwide public health problem, inflicting a complex constellation of physical and neuropsychiatric symptoms which are shown to progress with time. This research will investigate the potential of caloric vestibular stimulation (CVS), a non-invasive form of brain stimulation, as a treatment for individuals who suffer from Parkinson's Disease. Investigators will investigate whether core cognitive and physiological deficits are responsive to stimulation by comparing participants' performance on behavioral and physiological measures after baseline and either active or placebo stimulation phases with the aim of drawing initial insights into the application of CVS within this population. The study design is based on a single-case study that recently demonstrated durable, clinically meaningful gains in the motor and cognitive symptoms of PD.