Neurotransmitter - A specialized chemical messenger produced by nerve cells that helps nerves send messages to each other. Palsy - paralysis of a group of muscles. Parkinsonism - a group of diseases with symptoms similar to Parkinson's disease. Peripheral nervous system - The nerves that run throughout the body, connecting to the central nervous system at the spinal cord. PET scans map the brain's blood flow and metabolic activities, giving a clear picture of its biological functioning.
PET scans are non-invasive, painless and safe.
Secondary - Due to some other disorder. For example, a secondary dystonia is a symptom of some other disorder. Seizure - a disturbance of the brain's normal electrical activity, causing a temporary change in behavior, consciousness, bodily movements or sensation. Seizures are the main symptom of epilepsy, but can be caused by a wide variety of conditions. An unwanted effect of drug therapy.