title: The nucleus of the optic tract of the opossum.
abstract: This paper reviews anatomical and electrophysiological data on the nucleus of the optic tract (NOT) of the opossum, a nucleus in the afferent branch of the horizontal optokinetic reflex. It is proposed that subcortical routes are essential for responses from the two eyes: a direct retinal projection from the contralateral eye and a commissural pathway between the two NOTs for the ipsolateral eye. In the latter case there's evidence that the commisural axons have a relay on inhibitory neurones. This circuit accounts for the differences in response pattern under monocular condition: temporo-nasal motion of the visual stimulus elicits excitation in the contralateral NOT, resulting in inhibition of the ipsolateral nucleus, while naso-temporal motion promotes inhibition in the contralateral nucleus, releasing the ipsolateral nucleus from the commissural input.
authors.affiliation: Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Brasil.
authors.forename: E
authors.initials: E
authors.lastname: Volchan
authors.forename: A
authors.initials: A
authors.lastname: Pereira Júnior
authors.forename: C D
authors.initials: CD
authors.lastname: Vargas
authors.forename: C E
authors.initials: CE
authors.lastname: Rocha-Miranda
mesh_terms: D000818:Animals; D017120:Nystagmus, Optokinetic / Q000502:physiology*; D009893:Opossums / Q000502:physiology*