The Second Edition of this chart defines Parkinson's disease and illustrates the brain in various views. It lists the causes and risk factors of Parkinson's disease, describes and illustrates common signs and symptoms, and lists related symptoms such as decreased sense of smell, depression, and sleep problems. It describes various management and treatment options such as medications, surgery, and therapy, and shows an electrode brain implant on a figure with a mask-like expression. It explains the involvement of the brain with body movement and shows a figure with a tremor impulse coming from the brain down the arm. The chart also shows the role of neurotransmitters and describes the steps from a neuron receiving a message to post-message release of dopamine.