The New Jersey Institute of Technology's
Electronic Theses & Dissertations Project

Title:	The effect of vergence vision training on binocularly normal subjects
Author:	Talasan, Henry
View Online:	njit-etd2014-076 (x, 69 pages ~ 6.6 MB pdf)
Department:	Department of Biomedical Engineering
Degree:	Master of Science
Program:	Biomedical Engineering
Document Type:	Thesis
Advisory Committee:	Alvarez, Tara L. (Committee chair) Adamovich, Sergei (Committee member) Perez-Castillejos, Raquel (Committee member) Scheiman, Mitchell (Committee member)
Date:	2014-05
Keywords:	Vergence occular motor system Vision training Binocularly normal
Availability:	Unrestricted
Abstract:	Vergence is the disjunctive (inward or outward) movement of the eyes that is stimulated by retinal disparity (difference of where an image is projected to the retina and the fovea). A recent randomized clinical trial showed the efficacy of vision therapy for children with the binocular dysfunction known as convergence insufficiency is 73%. However, it is unknown whether binocularly normal persons will have any significant change to their vergence ocular motor system if they participate in vision training sessions. A total of ten (n = 10) binocularly normal persons participated in this study (18 to 28 years of age). A haploscope with an integrated infrared video-based eye tracking system manufactured by ISCAN presented vergence stimuli to the subject to record eye movement data before and after 12 hours of vision therapy with a custom LabVIEW program. Vision therapy entailed a random walk of 2° and 4° steps at near and far space along with ramps ranging from 1° to 20° of total vergence angular rotation. All processing and statistical analyses were conducted in MATLAB. All subjects experienced a significant decrease in time to peak velocity (p<0.05). However, each subject’s peak velocity values were subject dependent and either increased, decreased, or maintained at the same level after training. The peak velocity of responses to 2° steps began to approach a more critically damped linear control system after vision training supporting an improvement in the accuracy of responses. Data support that even in binocularly normal control subjects; vision therapy improves vergence eye movements quantified as significant improvements in the time to fuse the new target and significantly more accurate responses compared to each subject’s baseline measurements.