Introduction to the Diagnosis of Brain, Spinal Cord, and Nerve Disorders

ByMark Freedman, MD, MSc, University of Ottawa
Reviewed/Revised Aug 2023
VIEW PROFESSIONAL VERSION

    The nervous system consists of the brain, spinal cord, and nerves that connect the brain and spinal cord to the rest of the body (peripheral nerves).

    Doctors may suspect a problem with the brain, spinal cord, or nerves based on symptoms. Symptoms resulting from a disorder that affects part or all of the nervous system (a neurologic disorder) are called neurologic symptoms.

    Because the nervous system controls so many different body functions, neurologic symptoms can vary greatly. They can include the following:

    Neurologic symptoms may be minor (such as a foot that has fallen asleep) or life threatening (such as coma due to stroke).

    The characteristics and pattern of symptoms help doctors diagnose the neurologic disorder.

    When people have symptoms that suggest a neurologic disorder, doctors ask specific questions about the symptoms and other relevant factors (the medical history). Doctors usually also do a physical examination to evaluate all of the body systems, but they focus on the nervous system (called the neurologic examination).

    The neurologic examination helps doctors do the following:

    • Identify the location of the abnormality that is causing the symptoms

    • Determine whether the problem originates in the nervous system or elsewhere in the body but affects the nervous system (such as an infection, cancer, or an injury)

    • Determine whether tests are needed and, if needed, which tests should be done

    Diagnostic tests may be needed to confirm a diagnosis or exclude other possible disorders.

    quizzes_lightbulb_red
    Test your KnowledgeTake a Quiz!
    Download the free Merck Manual App iOS ANDROID
    Download the free Merck Manual App iOS ANDROID
    Download the free Merck Manual App iOS ANDROID