Gaze (physiology)

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The term gaze is frequently used in physiology to describe coordinated motion of the eyes and neck. The lateral gaze is controlled by the paramedian pontine reticular formation (PPRF).^[1] The vertical gaze is controlled by the rostral interstitial nucleus of medial longitudinal fasciculus and the interstitial nucleus of Cajal.

Conjugate gaze

The conjugate gaze is the motion of both eyes in the same direction at the same time, and conjugate gaze palsy refers to an impairment of this function. The conjugate gaze is controlled by four different mechanisms:^[2]

the saccadic system that allows for voluntary direction of the gaze
the pursuit system that allows the subject to follow a moving object
the optokinetic system that restores gaze despite movements of the outside world
the vestibulo-ocular reflex system (VOR system) that corrects for the movements of the head to preserve the stable visual image of the world

References

↑ "Neural Control of Saccadic Eye Movements -- Neuroscience -- NCBI Bookshelf". Retrieved 2009-11-29.
↑ Fowler, Timothy J.; John W. Scadding (2003). Clinical Neurology (3rd ed.). Arnold. ISBN 0-340-80798-9. Cite uses deprecated parameters (help)

External links

Sensory system: Visual system and eye movement pathways

Visual perception

1° (Bipolar cell of Retina) → 2° (Ganglionic cell) → 3° (Optic nerve → Optic chiasm → Optic tract → LGN of Thalamus) → 4° (Optic radiation → Cuneus and Lingual gyrus of Visual cortex → Blobs → Globs)

Muscles of orbit

Tracking	Smooth pursuit: Parietal lobe · Occipital lobe Saccade: Frontal eye fields Nystagmus → Fixation reflex → PPRF

Horizontal gaze	PPRF → Abducens nucleus → MLF → Oculomotor nucleus → Medial rectus muscle

Vertical gaze	Rostral interstitial nucleus → Oculomotor nucleus, Trochlear nucleus → Muscles of orbit

Vestibulo-ocular reflex	Semicircular canal → Vestibulocochlear nerve → Vestibular nuclei → Abducens nucleus → MLF (Vestibulo-oculomotor fibers) → Oculomotor nucleus → Medial rectus muscle

Pupillary reflex

Pupillary dilation	1° (Posterior hypothalamus → Ciliospinal center) → 2° (Superior cervical ganglion) → 3° (Sympathetic root of ciliary ganglion → Nasociliary nerve → Long ciliary nerves → Iris dilator muscle)

Pupillary light reflex (constriction)	1° (Retina → Optic nerve → Optic chiasm → Optic tract → Pretectal nucleus) → 2° (Edinger-Westphal nucleus) → 3° (Oculomotor nerve → Parasympathetic root of ciliary ganglion → Ciliary ganglion) → (4° Short ciliary nerves → Iris sphincter muscle)

Accommodation vergence	1° (Retina → Optic nerve → Optic chiasm → Optic tract → Visual cortex → Brodmann area 19 → Pretectal area) → 2° (Edinger-Westphal nucleus) → 3° (Short ciliary nerves → Ciliary ganglion → Ciliary muscle)

Circadian rhythm

Retina → Hypothalamus (Suprachiasmatic nucleus)

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