All parts of the brain › Eye movements

What part of the brain controls eye movements?

Six small muscles turn each eye, and three cranial nerves drive them: the oculomotor (III) and trochlear (IV) nerves from the midbrain and the abducens (VI) nerve from the pons. Gaze centres in the brainstem make both eyes move together (sideways from the pons, up and down from the midbrain). Where to look is chosen higher up: the frontal eye field in the frontal lobe and the superior colliculus in the roof of the midbrain both trigger the quick jumps of the eyes called saccades, and the cerebellum keeps the eyes on target and the gaze steady while the head moves. [1][2][3][4]

Not lit: the abducens nerve (the sixth cranial nerve), which leaves the brainstem where the pons meets the medulla and turns each eye outward through the lateral rectus muscle. The abducens nerve is not in this model: it is not a separate shape in the atlas (BodyParts3D 4.0), so no marker is placed at a guessed position. The lit oculomotor nerve is only its two branches inside the eye socket (the superior and inferior divisions), which is all of that nerve the atlas ships; its run from the midbrain to the socket is not part of the shape. [5][6][7]

The frontal eye field is a region on the middle frontal gyrus, not a separate shape. The 3D model has no shape for it, so the whole middle frontal gyrus is lit; the region’s exact border is not drawn.

The 3D brain needs JavaScript. The list of parts still says what each one does for eye movements.

Slice

All 7 parts are lit together. Drag to turn, pinch or scroll to zoom, tap a part on the brain or a name in the list to focus it; .

Eye movements: 7 parts lit

Superior colliculus, oculomotor nerve, trochlear nerve, midbrain, pons, middle frontal gyrus and cerebellum. Tap one to see where it is and what it does.

The parts and their roles

The upper pair of bumps on the roof of the midbrain: activity in its deep layers, set off by input from the retina or commands from the cortex, launches a saccade and turns the eyes and head toward something seen or heard. [8][2] Where is the superior colliculus?
Cranial nerve III works four of the six muscles of each eye (the superior, medial and inferior rectus and the inferior oblique) and the muscle that lifts the upper eyelid; it also carries the fibres that narrow the pupil and focus the lens for near sight. [6]
Cranial nerve IV works a single muscle, the superior oblique, which turns the eye down and in, as when reading or walking downstairs; it is the only cranial nerve that leaves the back of the brainstem, and the one with the longest course inside the skull. [9]
Holds the nuclei of the oculomotor and trochlear nerves, and at its lower end the rostral interstitial nucleus of the medial longitudinal fasciculus, the centre for moving both eyes up and down together. [10][6][4] Where is the midbrain?
Holds the abducens nucleus and, beside it, the paramedian pontine reticular formation: together they are the horizontal gaze centre, which turns both eyes left or right at once. [3][5] Where is the pons?
The frontal eye field sits in its back part, where it meets the precentral gyrus: the cortex’s control of voluntary saccades and smooth pursuit. [11][2] Where is the middle frontal gyrus?
Its flocculus, in the lowest part of the cerebellum, is an essential part of the vestibulo-ocular reflex that keeps gaze steady while the head turns, and carries an eye-velocity signal during smooth pursuit. [12] Where is the cerebellum?

Named areas on the lit gyri

The frontal eye field, on the : An area of cortex around where the back of the middle frontal gyrus meets the precentral gyrus (Brodmann area 8); it drives voluntary saccades and pursuit movements and helps steer visual attention. [11]

How they work together

A sideways glance needs two different muscles in the two eyes: the horizontal gaze centre in the pons drives the abducens nucleus on its own side, and through the medial longitudinal fasciculus the oculomotor nucleus on the other side, so one eye turns out while the other turns in. [3]
Saccades are fast and short: a large one (25° of visual angle) peaks at up to about 700° a second, most last about 20 to 200 ms, and when you look over a scene you fix your gaze two to three times a second. [2]
The vestibulo-ocular reflex moves the eyes opposite to the head, lagging it by less than 10 ms, so the picture on the retina stays still while you walk or turn; motor learning keeps adjusting how strongly it acts. [13][12]
Honest limit: many more areas take part than are lit here, including the supplementary eye fields, parietal areas such as the lateral intraparietal cortex, the visual cortex and the vestibular nuclei; the brainstem gaze centres are small nuclei inside the midbrain and pons with no shape of their own on this model, so the midbrain and pons are lit whole. [1][3]

Seeing and moving the eyes share the superior colliculus, which takes input straight from the retina and uses it to turn the eyes toward what appears in view. [8] What part of the brain controls vision?

Sources

Facts describe anatomy and normal function only. A part lit here takes part in eye movements; it does not do it alone, and it does other jobs too. The 3D model is the adult male BodyParts3D brain (credits and licence); on it the brainstem includes the midbrain, pons and medulla, so lighting the brainstem lights all three.