I. Lesions affecting the cortical connections to the nuclei of cranial nerves 3, 4 and 6, are termed SUPRANUCLEAR

II. Lesions affecting the connections between nuclei are INTERNUCLEAR    This would typically give rise to an internuclear ophthalmoplegia

III Lesions affecting the nuclei are NUCLEAR  Examples would be Wallenberg's and Parinaud's syndromes

IV. Lesions affecting the nerves, neuromuscular junction, or muscles are INFRANUCLEAR1               Lesions of Cranial Nerve 3, 4 and 6           Superior Oblique Myokymia              Duane Syndrome


Video 1. Supranuclear Gaze. Professor A Moodley, NASA Neurology Registrar Weekend, 2019




Supranuclear deficits arise from involvement of:
-Oculomotor control pathways above the level of the abducens nucleus for horizontal eye movements
-Oculomotor control pathways above the level of the structures (cranial nerves III and IV, and the interstitial nucleus of Cajal (INC) in the dorsal midbrain) for vertical eye movements

Supranuclear ocular motor disturbances usually impair the movement of both eyes, for example, resulting in the following:

The abducens nucleus, located in the pontine tegmentum, contains motor neurons that innervate the ipsilateral lateral rectus, as well as interneurons which decussate in the MLF, and innervate the contralateral medial rectus subnucleus.  Abducens nucleus involvement can be distinguished from abducens nerve injury in that a nuclear lesion produces a gaze palsy to the side of the lesion, whereas nerve injury produces only a lateral rectus palsy. 

Lesions of the nucleus make the vestibular ocular reflexes (VOR) dysfunctional, and the gaze palsy arising from a nuclear lesion therefore cannot be overcome by oculocephalic testing or caloric stimulation, as opposed to supranuclear lesions, or lesions of the PPRF.  This indicates that the abducens nucleus is a central integrating final common pathway for horizontal eye movements, as is the INC for vertical eye movements 2.  

Bilateral pontine injury can abolish all horizontal eye movements. This devastating injury still allows vertical eye movements, which often occur spontaneously (ie, ocular bobbing).
Congenital horizontal gaze palsy can occur as part of Möbius syndrome, in which aplasia of the CN VI nuclei is accompanied by bilateral facial paresis.






  1. Glisson CC. Approach to Diplopia [published correction appears in Continuum (Minneap Minn). 2020 Feb;26(1):240]. Continuum (Minneap Minn). 2019;25(5):1362-1375. doi:10.1212/CON.0000000000000786
  2. Strupp M, Kremmyda O, Adamczyk C, et al. Central ocular motor disorders, including gaze palsy and nystagmus. J Neurol. 2014;261 Suppl 2:S542-58