The facial nerve (cranial nerve VII) leaves the brainstem at the border of the pons and the medulla oblongata (the pontomedullary junction), between the abducens (VI) and vestibulocochlear (VIII) nerves. It enters the temporal bone through the internal acoustic meatus, winds through the facial canal and leaves the skull through the stylomastoid foramen to reach the muscles of the face. [1][2]
The 3D brain needs JavaScript. The text below still says where the facial nerve is and what it does.
The pons and medulla oblongata are lit together; the facial nerve leaves at their border and is not drawn on its own. The side (sagittal) slice button cuts through them. Drag to turn, pinch or scroll to zoom, tap any part to name it; .
Not a separate shape in this atlas; lit: the part it leaves the brain from. Lit: the whole pons and the whole medulla oblongata together, since the facial nerve leaves at their border. The nerve itself has no shape in the BodyParts3D model, so nothing is drawn for it at a guessed point. [3][2]
Where it leaves the brain: the border of the pons and the medulla oblongata, the pontomedullary junction, out at the side where they meet the cerebellum (the cerebellopontine angle). Its motor fibres start in the facial nucleus in the pons. [2][1][4]
Lit here: the pons and the medulla oblongata, the parts the facial nerve leaves the brain from, at their border — see each on its own page.
It has two parts that leave together: the motor root, from the facial nucleus in the pons, and the smaller intermediate nerve, which carries its taste, sensory and gland fibres. [1]
It crosses the back of the skull (the posterior cranial fossa) and enters the temporal bone through the internal acoustic meatus, together with the vestibulocochlear nerve. [1][5]
Inside the bone it takes a winding course through the facial canal. At its first bend, the geniculum, sits the geniculate ganglion, which holds the cell bodies of its taste fibres. [1]
It leaves the skull through the stylomastoid foramen, passes through the parotid gland without supplying it, and splits into five branches for the face: temporal, zygomatic, buccal, marginal mandibular and cervical. [1]
What it does
It works the muscles of facial expression through its five branches, plus a few more: the stapedius in the middle ear, the back belly of the digastric, the stylohyoid and small muscles of the scalp around the ear. [1][6]
Through its chorda tympani branch it carries taste from the front two-thirds of the tongue. [1][6]
It drives glands: the tear (lacrimal) gland and glands of the nose and palate through the greater petrosal nerve, and the submandibular and sublingual salivary glands through the chorda tympani. [1]
Connections
From the brainstem: the facial nucleus (to the face muscles) and the superior salivatory nucleus (to the glands), both in the pons. Into the brainstem: taste from the tongue to the upper (gustatory) part of the solitary nucleus. [1]
Other names
Cranial nerve VII (CN VII), seventh cranial nerve; nervus facialis (Latin). With its intermediate nerve it is also called the nervus intermediofacialis. [1]
Size
The model has no shape for the facial nerve, so it is not measured here. The pons, lit as the part it leaves the brain from, measures about 34 mm front to back, 29 mm top to bottom and 42 mm side to side on this model (the box it fits in, not its volume). [3]
The medulla oblongata, lit as the part it leaves the brain from, measures about 33 mm front to back, 41 mm top to bottom and 27 mm side to side on this model (the box it fits in, not its volume). [3]
Facts describe anatomy and normal function only. The 3D model is the adult male BodyParts3D brain (credits and licence); real brains vary in size and shape, so its measurements describe one model, not anyone’s brain.