A neurologist is a medical doctor who specializes in the diagnosis and treatment of diseases and disorders of the nervous system. They are experts in the field of neurology, which is the study of the structure, function, and diseases of the nervous system. Neurologists may diagnose and treat conditions such as stroke, multiple sclerosis, Parkinson's disease, Alzheimer's disease, epilepsy, and other neurological disorders. They may also perform tests such as EEGs, CT scans, and MRIs to help diagnose and treat their patients.