Introduction The forebrain controls eye movement via frontal eye fields (FEF) which are involved in generating contralateral saccades via the contralateral paramedian pontine reticular formation (PPRF) clinical correlate right-way eyes lesions at the cerebral hemispheres (e.g., stroke) that affects the FEF results in the eyes looking toward the side of the lesion wrong-way eyes a seizure at the FEF will result in the eyes looking away from the side of seizure activity thalamic hemorrhages for unknown reasons Cranial nerves involved in eye movements oculomotor nerve (CN III) innervates all of the extraocular muscles except superior oblique muscle lateral rectus muscle medial rectus → adducts eye superior rectus → elevates and intorts inferior rectus → depresses and extorts may become entraped during orbital floor fractures, leading to limited vertical eye movement inferior oblique → elevates and extorts a lesion results in horizontal and vertical diplopia in cases of complete one-sided CN III palsy results in ptosis mydriasis inability to adduct, elevate, and depress the eye the eye resting in an down-and-out and intorted position trochlear nerve (CN IV) superior oblique muscle → depresses and intorts a lesion results in vertical diplopia that worsens with downgaze can reduce diplopia by tilting head away from the side of the lesion abducens nerve (CN VI) lateral rectus → abducts the eye a lesion results in horizontal diplopia Clinical correlate medial longitudinal fasciculus (MLF) function these are heavily myelinated fibers that interconnects the oculomotor nuclei trochlear nuclei abducens nuclei vestibular nuclei lesion internuclear ophthalmoplegia a lesion affecting the ipsilateral MLF will impair adduction of the ipsilateral medial rectus (and thus a horizontal gaze palsy) notes can have nystagmus of the opposite eye for unknown reasons bilateral MLF lesions are commonly found in multiple sclerosis causes impaired adduction of both eyes during gaze towards the opposite side