Author ORCID Identifier
0000-0003-4151-4940
Document Type
Dissertation
Date of Award
5-31-2026
Degree Name
Doctor of Philosophy in Biomedical Engineering - (Ph.D.)
Department
Biomedical Engineering
First Advisor
Tara L. Alvarez
Second Advisor
Suril Gohel
Third Advisor
Chang Yaramothu
Fourth Advisor
Nancy D. Chiaravalloti
Fifth Advisor
Mitchell Scheiman
Abstract
Binocular dysfunctions are more prevalent in the persistent post-concussive symptoms (PPCS) population than in the general population. The most prevalent binocular disorder is convergence insufficiency (CI), affecting 3-17% of the general population and up to 10 times as many people with PPCS. CI makes it difficult to fuse or maintain fusion on targets at near, and its symptoms include double or blurry vision and headaches when performing close-range tasks such as reading, which can exacerbate PPCS symptoms. Given controversy over the subjectivity and effectiveness of diagnostic tools and symptom surveys for both PPCS and CI, understanding why CI has high comorbidity with PPCS and the distinct etiology of concussion-related CI (CONC-CI) will help develop objective measures and better treatments for both disorders.
This work addresses gaps in understanding the neural systems underlying vergence in normal controls, how the vergence system of CONC-CI differs from controls, and how office-based vergence and accommodative therapy with movement (OBVAM) may remediate the vergence system and visual symptoms. This study utilizes functional magnetic resonance imaging to delineate the neural mechanisms of vergence in CONC-CI compared to binocularly normal controls (BNC) and the OBVAM, a therapeutic intervention suggested to remediate visual symptoms post-concussion. Specifically, the gap is addressed with the following goals: 1) identify the efferent pathway of the vergence motor system in binocularly normal controls correlated to clinical measures, 2) elucidate the difference in the vergence network between CONC-CI and BNC with correlations to clinical measures, and 3) understand the underlying neural mechanism by which OBVAM improves visual symptoms in the CONC-CI group with correlations to clinical measures.
A total of 66 adolescents and young adults with CONC-CI and 46 BNC participants from ages 11 to 25 are recruited. Using just the BNC data, activity in the supplemental eye field, parietal eye field, cerebellum, and visual cortex are implicated in efferent vergence eye movements. Using single fMRI scans from controls and longitudinal fMRI scans from patients, the results show that there are system-level differences in the vergence circuits between controls and patients. Specifically, these differences occur in the oculomotor circuit, including the cerebellum, frontal eye fields, parietal eye fields, supplemental eye fields, and the visual cortex. Therapeutic intervention also has a significant effect on these regions of interest, specifically increasing their spatial extent and the strength of activation. The primary effect occurs in the visual cortex and the cerebellum. This dissertation is among the first to study neural mechanisms in individuals with CONC-CI using fMRI, rather than focusing solely on clinical signs and symptoms. The findings of this project provide insight into the vergence circuit, the etiology of CONC-CI, and how vision therapy improves visual function. In the long term, the application of this knowledge can lead to individualized therapy and improve and standardize therapeutic measures for CONC-CI.
Recommended Citation
Sangoi, Ayushi, "Vergence task-based neural pathways with binocularly normal vision and comorbid persistent post-concussive symptoms -convergence insufficiency" (2026). Dissertations. 1888.
https://digitalcommons.njit.edu/dissertations/1888
Included in
Bioelectrical and Neuroengineering Commons, Bioimaging and Biomedical Optics Commons, Computational Neuroscience Commons, Medical Neurobiology Commons, Vision Science Commons
