The nervous system can be divided in three main parts: central, peripheral and autonomic. The central nervous system refers to the command centers such as the brain and the spinal cord. The peripheral nervous system includes nerves and muscles that connect the central nervous system with the rest of the body. The autonomic nervous system regulates vital "involuntary" functions such as the blood pressure, sweat, heart rhythm and rate, and breathing.

During a neurological exam, the neurologist reviews the history of the patient's complaints health, with emphasize in the present illness. The clinical neurological exam includes an evaluation of the mental status, function of the cranial nerves (vision, etc), strength, coordination, reflexes, and sensitivity. This information helps the neurologist to determine the existence of a neurological problem and its location in nervous system. Additional tests may be necessary to confirm a diagnosis and guide the most appropriate treatment. Some of the most common neurological symptoms are dolor, fatigue, sleep disturbance, weakness, abnormal sensations, abnormal movements, seizures, forgetfulness, attention deficits, poor concentration, abnormal thoughts and/or emotions, etc.