Diseases affecting the brain, nervous system and spinal cord are usually diagnosed with a neurologic examination. This is not to be confused with a psychiatric examination, which predominantly focuses on a patient's mental state and behaviour. It is important to understand that mental illnesses are typically classified separately from disorders of the central nervous system. Major neurological disorders include cerebral palsy, speech and language disorders, tumours of the brain, and movement disorders such as Parkinson's disease and Huntington's disease.
Surgery on the brain, spinal cord, and nerves may generally be described as neurosurgery, or neurological surgery. Conditions that may require neurosurgery include head trauma, which may arise as a result of skull fractures. Brain tumours and tumours of the spine, spinal cord and peripheral nerves may also require surgical removal by a trained neurosurgeon.