Overview
Classification of cranial nerve fibers and nuclei Sensory (afferent) modalities:
- General somatic sensory (GSS) – general sensation from skin.
- General visceral sensory (GVS) – general sensation from viscera.
- Special somatic sensory (SSS) – senses derived from ectoderm (e.g. sight, sound, balance).
- Special visceral sensory (SVS) – senses derived from endoderm (e.g. taste, smell).
Motor (efferent) modalities:
- General somatic motor (GSM) – skeletal muscles.
- General visceral motor (GVM) – smooth muscles of gut and autonomic motor.
- Special visceral motor (SVM) – muscles derived from pharyngeal arches.
| 1 (CN I) | Olfactory nerve | Cribriform plate | Sensory (SVS) | Smell |
| 2 (CN II) | Optic nerve | Optic canal | Sensory (SSS) | Vision |
| 3 (CN III) | Oculomotor nerve | Superior orbital fissure | Motor (GSM & GVM) | GSM: 4 extrinsic eye muscles and levator palpebrae superioris. GVM: pupillary sphincter |
| 4 (CN IV) | Trochlear nerve | Superior orbital fissure | Motor (GSM) | Superior oblique |
| 5 (CN V) | Trigeminal nerve | |||
| Ophthalmic | Superior orbital fissure | GSS | Scalp, forehead and nose. | |
| Maxillary | F. rotundum | GSS | Cheeks, lower eye lid, nasal mucosa, upper lip, upper teeth and palate. | |
| Mandibular | F. ovale | GSS SVM | GSS: anterior 2/3 tongue, skin over mandible and lower teeth. SVM: muscles of mastication. | |
| 6 (CN VI) | Abducens nerve | Superior orbital fissure | Motor (GSM) | Lateral rectus |
| 7 (CN VII) | Facial Nerve | Internal acoustic meatus > stylomastoid f. | Both: GSS SVS SVM GVM | GSS: sensation to part of ext. ear. SVS: taste from ant. 2/3 tongue, hard and soft palate. SVM: muscles of facial expression. GVM: lacrimal, submandibular, sublingual glands and mucous glands of mouth and nose. |
| 8 (CN VIII) | Vestibulocochlear nerve | Internal acoustic meatus | Sensory (SSS) | Hearing and balance |
| 9 (CN IX) | Glossopharyngeal Nerve | Jugular f. | Both: GSS GVS SVS GVM SVM | GSS: post. 1/3 tongue, ext. ear, and middle ear cavity. GVS: carotid body and sinus. SVS: taste from post. 1/3 tongue. GVM: parotid gland. SVM: stylopharyngeus |
| 10 (CN X) | Vagus Nerve | Jugular f. | Both: GSS GVS SVS GVM SVM | GSS: ext. ear, larynx and pharynx. GVS: larynx, pharynx and, thoracic & abdominal viscera. SVS: taste from epiglottis region of tongue GVM: smooth muscles of pharynx, larynx and most of the GIT. SVM: most muscles of pharynx and larynx. |
| 11 (CN XI) | Spinal accessory nerve | Jugular f. | Motor (GSM & SVM) | GSM: trapezius and sternocleidomastoid. SVM: a few fibres run with CNX to viscera. |
| 12 (CN XII) | Hypoglossal Nerve | Hypoglossal canal | Motor (GSM) | Intrinsic and extrinsic tongue muscles (except the palatoglossus). |