A neurologist is a physician concerned with diagnosis and treatment of all categories of disease involving the central and peripheral nervous system. They treat medical conditions such as stroke, epilepsy, headaches, neck and back pain, and Parkinson's Disease. They work closely with neurologic surgeons and refer to them when they think a neurologic problem may respond to surgery. Neurologists use a variety of techniques and technology to assist them in evaluating and diagnosing neurologic disorders. Disorders may fall into the central nervous system- brain and spinal column, peripheral nervous system-the nerves that cause the body to function and have sensation, or the musculoskeletal system-when the nerve muscle interactions may be responsible for symptoms.