Freezing of gait (FOG) is a common, disabling symptom of later stage Parkinson's disease (PD), and can induce significant morbidity and mortality by increasing risk of falls as the disease progresses. Despite optimum medical management and deep brain stimulation therapy, many patients with PD are incapacitated by FOG and gait disorders. Non-invasive vibrotactile stimulation has been reported to potentially improve FOG of patients with PD. However, results of studies were variable, and there is a lack of convenient vibrotactile devices ready for daily use with reliable clinical trial data. In the proposed study, the investigator will test the effect of a newly developed vibrotactile foot device (Smart shoe) on participants diagnosed with PD and FOG. EEG and fMRI are obtained in order to investigate the underlying neurological mechanism.