Edinger-Westphal-Kern

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The Edinger-Westphal nucleus ( nucleus accessory nervi oculomotorii ) is the origin of the parasympathetic nerve fibers of the third cranial nerve ( nervus oculomotorius ) and lies in the midbrain . It was named after the discoverers Ludwig Edinger and Carl Friedrich Otto Westphal .

This core area controls the pupillary reflex and thus the adaptation of the eye. The nucleus receives its afferents from the optic nerve and the optic tract , whereby these nerve fibers do not project via the corpus geniculatum laterale , but directly into the epithalamus . Here they are switched to interneurons in the pretectal nucleus , which then move to the Edinger-Westphal nucleus on both sides. Its efferents pass over the ciliary ganglion to the pupil constriction and to the ciliary muscle .

A failure of the Edinger-Westphal nucleus manifests itself in a widening of the pupil ( mydriasis ) due to the overweight of the sympathetic nervous system, i.e. the dilatator pupillae muscle , as well as the inability to close accomodation (due to paralysis of the ciliary muscle). This leads to hypersensitivity to light and the inability to see close objects clearly.

literature

  • Martin Trepel: Neuroanatomy. Structure and function . 3rd edition. Urban & Fischer, Munich 2003. ISBN 3-437-41297-3 .
  • Franz-Viktor Salomon: nervous system, systema nervosum . In: Franz-Viktor Salomon, Hans Geyer, Uwe Gille (Ed.): Anatomy for veterinary medicine . Enke, Stuttgart, 2004, pp. 464-577. ISBN 3-8304-1007-7 .