The Amniote Oculomotor Complex

Abstract

The oculomotor (OM) complex is a combination of somatic and parasympatethic neurons. The correct development and wiring of this cranial pair is essential to perform basic functions: eyeball and eyelid movements, pupillary constriction, and lens accommodation. The improper formation or function of this nucleus leads pathologies such as strabismus. We describe the OM organization and function in different vertebrate brains, including chick, mouse, and human. The morphological localization is detailed, as well as the spatial relation with the trochlear nucleus in order to adjust some misleading anatomical topographic descriptions. We detailed the signaling processes needed for the specification of the OM neurons. The transcriptional programs driven the specification and differentiation of these neurons are partially determined. We summarized recent genetic studies that have led to the identification of guidance mechanisms involved in the migration, axon pathfinding, and targeting of the OM neurons. Finally, we overviewed the pathology associated to genetic malformations in the OM development and related clinical alterations. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc.

A Review of Third Nerve Palsies

“…OMNC is subdivided into 3 larger subnuclei: central subnucleus, lateral subnucleus, and EWN. 4 Central subnucleus contains medial subnuclei, which innervates the contralateral superior rectus muscle, and a single central caudal subnucleus, which innervates both levator palpebrae superioris. 5,6 Clinical Pearl…”

Cranial Nerves: Mind Your Head

“…This Special Issue of The Anatomical Record compiles works in the above mentioned Ontogeny/Phylogeny and Morphology/Clinical Significance topics. The organizational/developmental point of view (Volume 1 of this Special Issue) is populated with the long debated cranial par 0 or nervus terminalis (Peña‐Melián et al ., ), the very atypical and interesting features of the olfactory nerve (Crespo et al ., ), the development and pathologies of optic nerves (Herrera et al ., ), the organization and function of the oculomotor complex in different vertebrate brains, and the complex evolutionary relationships derived from the comparative analysis of eye muscles innervation (Company et al ., ; Ferran and Puelles, ), the anatomy and physiology of the auditory portion of the VIIIth nerve and the segmental organization of vestibular complex afferents and efferents (Carricondo and Romero‐Gómez, ; Diaz and Puelles, ), the atypical features of the spinal accesory motor neurons and the present neuromeric brainstem conception (prosomeric model) after new data from the visceral cranial nerve efferents (Puelles et al ., ; Watson and Tvrdik, ), and characterization of the cranial nerves in lampreys (Pombal and Megías, ). This volume 1 Ontogeny/Phylogeny of the Cranial Nerves Special Issue is completed with a historical overview of the cranial nerves (Porras et al ., ).…”

Cranial Nerves: Phylogeny and Ontogeny

“…The phylogeny and ontogeny volume includes an historical review (Porras‐Gallo et al, ), a review from a segmental perspective (Puelles et al, ), two comparative contributions on amphioxi (Ferran and Puelles, ) and lampreys (Pombal and Megías, ), and articles devoted to cranial nerves zero (Peña‐Melián et al, ), I (Crespo et al, ), II (Herrera et al, ), III, IV and VI (Company et al, ), VIII cochlear (Carricondo and Romero‐Gómez, ) and vestibular (Diaz and Puelles, ), and XI (Watson and Tvrdik, ).…”

“…The amniote oculomotor complex is reviewed from a comparative point of view (Company et al, ). The oculomotor complex includes somatic and parasympathetic neurons essential for eyeball and eyelid movements, pupillary constriction, and lens accommodation.…”