Stimulation of Pontine Reticular Formation in Monkeys With Strabismus

• DOI: 10.1167/iovs.13-12924
• Publication Date: 2013-10-11T13:19:07Z
• Authors: Mark M. G. Walton; Seiji Ono; Michael J. Mustari
• Keywords: Abducens nucleus; Oculomotor nucleus; Medial longitudinal fasciculus; Pons

Purpose.: Saccade disconjugacy in strabismus could result from any of a number factors, including abnormalities eye muscles, the plant, motoneurons, near response cells, or atypical tuning neurons saccade-related areas brain. This study was designed to investigate possibility that saccade is associated with paramedian pontine reticular formation (PPRF). Methods.: We applied microstimulation 22 sites PPRF and 20 abducens nucleus three rhesus macaque monkeys (one normal, one esotrope, exotrope). Results.: When mean velocity compared between two eyes, slight difference found for 1/5 normal animal. Significant differences were 5/6 an esotrope 10/11 exotrope. For five strabismic monkeys, directions evoked movements differed by more than 40° eyes. stimulation (20 sites), ipsilateral moved faster 4/6 animal all nine esotrope. exotrope, however, left always faster, even on right side. animals, often caused different move PPRF. Conclusions.: These data suggest organized at least partly monocularly disconjugate saccades are consequence unbalanced saccadic commands being sent