Neurology is a medical specialty dealing with disorders of the nervous system. To be specific, it deals with the diagnosis and treatment of all categories of disease involving the central (brain and spinal cord), peripheral, and autonomic nervous systems, including their coverings, blood vessels, and all effector tissue, such as muscle. The corresponding surgical specialty is neurosurgery. A neurologist is a physician specializing in neurology and trained to investigate, or diagnose and treat neurological disorders. Neurologists may also be involved in clinical research, and clinical trials, as well as basic research and translational research.