WATCH | Scientists awaken 'ghosts' in Parkinson’s patients

Scientists in Switzerland have devised a way of awakening the 'ghosts' hidden in the brains of Parkinson's disease sufferers to help evaluate their mental health.

Parkinson's disease is a brain disorder that leads to shaking, stiffness, and difficulty with walking, balance, and coordination.

Parkinson's symptoms usually begin gradually and get worse over time. As the disease progresses, people may have difficulty walking and talking.