Disturbances of Conjugate Horizontal Eye Movements in the Monkey

Abstract

Although it is generally accepted that enduring disturbances of conjugate horizontal eye movements most frequently are associated with lesions involving the dorsal pontine tegmentum, precise identification of the pontine "center for lateral gaze" has proved to be difficult. This so-called center, commonly regarded to be either in the abducens nucleus or in its immediate vicinity, has been referred to by some authors⁴⁵ as the parabducens nucleus. While a definitive description of this entity has not been found in the literature, certain authors^16,17,38 acknowledge its theo retical existence. The hypothesis suggesting that the abducens nucleus and the "center for lateral gaze" in the pons may constitute a single entity is supported by clinicopathological reports in which minute or restricted lesions in this nucleus have been associated with paralysis of conjugate horizontal gaze to the side of the lesion.^* Similar, but less wellfounded, conclusions have been drawn from clinicopathological material