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8.5: Cranial Nerves

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    124859
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    There are twelve pairs of cranial nerves attached to the brain. There are three sensory cranial nerves, five motor cranial nerves, and the rest are mixed (carrying both sensory and motor information) nerves. All cranial nerves are part of the peripheral nervous system. Each cranial nerve (CN) is designated a roman numeral from 1 to 12 (I to XII). So for example, the olfactory nerve is cranial nerve 1 so it is CN I.

    The cranial nerves are as follows:

    1. Olfactory nerve (CN I) (Sensory) (However, only the olfactory bulb and olfactory tract are visible when viewing the brain)
    2. Optic nerve (CN II) (Sensory)
    3. Oculomotor nerve (CN III) (Motor)
    4. Trochlear nerve (CN IV) (Motor)
    5. Trigeminal nerve (CN V) (Mixed)
    6. Abducens nerve (CN VI) (Motor)
    7. Facial nerve (CN VII) (Mixed)
    8. Vestibulocochlear nerve (CN VIII) (Sensory)
    9. Glossopharyngeal nerve (CN IX) (Mixed)
    10. Vagus nerve (CN X) (Mixed)
    11. Accessory nerve (CN XI) (Motor)
    12. Hypoglossal nerve (CN XII) (Motor)
    Diagram of the brain showing various cranial nerves, labeled with their names, including the olfactory bulb and optic nerve.
    Figure \(\PageIndex{1}\) The Cranial Nerves. (Image credit: "Cranial Nerves" by Justin Greene and Jennifer Lange is licensed under CC BY-NC-SA 4.0.) / Olfactory bulb and tract labels by Harmony Folse

    This page titled 8.5: Cranial Nerves is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by .