Cranial Nerves

Inferior surface of the brain as it appears on gross dissection.

The Olfactory nerve (I) – for sense of smell. Nerves in nasal cavity synapse within olfactory bulbs.

The Optic nerve (II) - carries visual information.

The Oculomotor nerve (III) - Controls 4 of the 6 extrinsic muscles of the eye. The Trochlear nerve (IV) Innervates superior oblique eye muscle.

The Trigeminal nerve (V) Largest of all the cranial nerves Has 3 Branches 1) Ophthalmic branch skin, lacrimal gland 2) Maxillary branch lower eyelid, upper jaw 3) Mandibular branch tongue, lower teeth

The Abducens nerve (VI) Innervates lateral rectus muscle of eye (abduction!) The Facial nerve (VII) Controls muscles of scalp and facial expression. Muscles of mastication and speech. Pressure sensations from face. Taste sensations from anterior 2/3 of tongue.

The Facial nerve (VII)

The Vestibulocochlear nerve (VIII) Monitors sense of balance, position and movement and also monitors hearing.

The Glossopharyngeal nerve (IX) Taste sensation from posterior 1/3 tongue. Controls swallowing Detects O2 and CO2 content of blood in carotid artery.

The Vagus nerve (X) Vital to autonomic control of visceral function

The Accessory nerve (XI) Internal branch Innervates swallowing muscles. External branch Controls sternocleidomastoid and trapezius. The Hypoglossal nerve (XII) Voluntary food mixing, swallowing and speech. Control of tongue movements.

The Accessory nerve (XI) and Hypoglossal nerve (XII)

Olfactory Nerve (II)

Fig 18.6 FYI

Optic Nerve (II)

Oculomotor Nerve (III) Trochlear Nerve (IV) Abducens Nerve (VI)

Trigeminal Nerve (V)

Facial Nerve (VII)

Vestibulocochlear Nerve (VIII)

Glossopharyngeal Nerve (IX)

Vagus Nerve (X)

Accessory Nerve (XI) Hypoglossal Nerve (XII)

Fig 18.17

FYI