A cornerstone in PD research is the investigation of neurophysiological changes as potential biomarkers that could help in tracking disease progression and response to therapies. Electroencephalography (EEG) could provide a non-invasive and relatively cheap tool for identification of such biomarkers. In this study we will use high-density electroencephalograph (EEG) recording, in order to develop a platform of biomarkers that could be more sensitive and reliable to disease progression and response to therapeutic intervention than standard clinical measures.

Inclusion Criteria:

1. Idiopathic PD patients (according to the UK PD Society brain bank clinical diagnostic criteria (bradykinesia plus at least one other cardinal feature of PD, no atypical features or secondary cause) and HC aged 40-80 years
2. PD patients Hoehn and Yahr stages I to IVStable PD therapy

Exclusion Criteria:

• In the investigator's opinion, any unstable or clinically significant condition that would impair the participants' ability to comply with study requirements.
• Patients or HC with significant psychiatric symptoms or history
• BDI score <14
• MMSE <25
• Treatment with neuroleptics.
• For PD patients: Hoehn and Yahr Stage 5
• PD Patients with severe dyskinesia or tremor
• PD Patients with atypical Parkinsonism or secondary Parkinsonism
• History or evidence of neurological problems: cerebrovascular disease, previous head injury or neurosurgical interventions.
• Currently with lice or open wounds on scalp.
• Significant sensory deficits, e.g., deafness or blindness
• Current drug abuse or alcoholism.
• Pregnancy or not using a reliable method of birth control.
• Participation in current clinical study or clinical study within 30 days prior to this study.

50 patients with idiopathic Parkinson's disease (PD) 50 Healthy controls (HC)