Ayushi Sangoi ¹ Farzin Hajebrahimi ¹ Suril Gohel ² Mitchell Scheiman ³ Tara Lynn Alvarez ^1*

• ¹ Biomedical Engineering, New Jersey Institute of Technology, Newark, United States
• ² Department of Health Informatics, Rutgers University School of Health Professions, Newark, United States
• ³ Philadelphia College of Optometry Drexel University, Philadephia, United States

Introduction: The vergence neural system was stimulated to dissect the afferent and efferent components of symmetrical vergence eye movement step responses. The hypothesis tested was whether the afferent regions of interest would differ from the efferent regions to serve as comparative data for future clinical patient population studies. Methods: Thirty binocularly normal participants participated in an oculomotor symmetrical vergence step block task within a functional MRI experiment compared to a similar sensory task where the participants did not elicit vergence eye movements. Results: For the oculomotor vergence task, functional activation was observed within the parietal eye field, supplemental eye field, frontal eye field, and cerebellar vermis, and activation in these regions was significantly diminished during the sensory task. Differences between the afferent sensory and efferent oculomotor experiments were also observed within the visual cortex. Discussion: Differences between the vergence oculomotor and sensory tasks provide a protocol to delineate the afferent and efferent portion of the vergence neural circuit. Implications with clinical populations and future therapeutic intervention studies are discussed.