Master of Science, The Ohio State University, 2022, Vision Science

In order to introduce a relatively quick suprathreshold visual field test that considers binocular interactions, a binocular visual field (BVF) stimulus was designed using dichoptic presentation to allow subjects to report their perceptions of the BVF stimulus. Study 1 first utilized neutral density filters to demonstrate the change in perceived luminance and contrast sensitivity. These neutral density filters were then used to simulate ocular disease in healthy subjects to disrupt the balance between the two eyes, which altered perception of the BVF test stimulus. In Study 2, glaucoma subjects with known visual field defects on a Humphrey Field Analyzer completed the BVF test. Threshold and pattern deviation data were compared to their perceptions of the BVF test. The BVF test design uses more natural viewing conditions and is fairly inexpensive and portable, which could be beneficial in certain clinical environments.

Committee: Teng Leng Ooi (Advisor); Roanne Flom (Committee Member); Bradley Dougherty (Committee Member) Subjects: Ophthalmology; Optics

Master of Science, University of Toledo, 2021, Exercise Science

Context: Patients continue to report high-reinjury rates, low rates of return to sport (RTS), and poor long-term function, with only 44-55% of athletes reaching full return to competitive sports. RTS tests inadvertently fail to consider the complex dynamics of sport (e.g. reactive and cognitive-motor demands associated with rapidly changing environment), which may threaten their utility in preventing subsequent injury. Objective: To establish within and between session test-retest reliability of two novel reactive agility tasks (Aim 1) and to assess the influence of a challenging visual constraint (e.g. stroboscopic visual field disruption) on participants' reaction time, time to target, total targets achieved and time to completion (Aim 2) Design: Descriptive case series with a test-retest design. Participants: Three healthy, physically active participants (Male n = 1 Female n = 2) aged 18-30 years old participated. Intervention: Participants completed two novel reactive agility tasks in a randomized order. Each participant completed 2 sessions approximately 7 days apart. Each session consisted of two sub-sessions that were identical excluding task order randomization and the addition of stroboscopic glasses during session 2b. After each task the participants completed the NASA-TLX survey. Main Outcome Measures: Task 1 outcomes included: Average Reaction Time (seconds), Average Time To Target (seconds), Number of Target Deactivations (n = #) Task 2 outcomes included: Average Time To Target (seconds), Number of Target Deactivations (n = #), Time to Completion (seconds). The NASA-TLX survey results were included as a secondary outcome measure for both tasks. Results: Overall, the ICC values for within and between session reliability of reaction time were moderate to weak and with wide confidence intervals (within: ICC = 0.782, 95% CI .000-.994, between: ICC = 0.318, 95% CI .000-.975). ICC values for time to completion, time to target and number of target de (open full item for complete abstract)

Committee: Grant Norte PhD, ATC, CSCS (Committee Chair); David Bazett-Jones PhD, ATC, CSCS (Committee Member); Amanda Murray PhD, DPT, PT (Committee Member) Subjects: Health Care; Health Sciences; Kinesiology; Neurosciences; Physical Therapy; Rehabilitation; Sports Medicine

Master of Science, The Ohio State University, 2018, Vision Science

Purpose: The use of bioptic telescopic spectacles (BTS) to obtain licensure for driving is currently legal in over 42 states, yet questions remain about performance and safety. The effect of BTS on sign identification distance is unknown. Previous studies reported worse ratings for lane position and steering steadiness in bioptic drivers, but were unable to report differences attributable to BTS use due to safety concerns with on-road testing. This study utilizes a driving simulator to compare sign identification performance with and without BTS use, and to compare bioptic and normally-sighted drivers. Velocity, lane position, and lane deviations are also examined. Additionally, self-ratings of quality of driving, avoidance, dependence, and driving space are examined. Methods: Bioptic drivers and controls were recruited from The Ohio State University College of Optometry. Visual acuity, contrast sensitivity, and visual field were assessed. The study was completed in a six-degree-of-freedom driving simulator equipped with a 260° curved front screen simulator with side mirror LCD displays and a screen seen through the rear-view mirror. Subjects completed a 32,000 meter straight four-lane highway course with light traffic and a speed limit of 45 mph. The main task was to press a button on the steering wheel whenever a target city name or route number road sign was confidently identified amongst distractor signs. This task was completed twice, once using the BTS and once without. Paired t-tests were used to analyze differences in sign recognition distance, velocity, lane position and steering entropy. Differences in the number and duration of lane deviations were also examined. Results: Twelve bioptic drivers and six controls participated. Mean±SD bioptic driver age was 56±17 and 55±10 for controls. Mean logMAR VA OU for bioptic drivers was 0.80±0.17 (20/125) and mean log CS was 1.48±0.16. Mean VA with telescope was 0.21±0.10 (20/32). The mean sign identification d (open full item for complete abstract)

Committee: Bradley Dougherty OD, PhD (Advisor); Thomas Raasch OD, PhD (Committee Member); Aaron Zimmerman OD, MS (Committee Member) Subjects: Ophthalmology; Optics

Doctor of Philosophy, The Ohio State University, 1987, Graduate School

Committee: Not Provided (Other) Subjects: Education

Doctor of Philosophy, The Ohio State University, 2016, Computer Science and Engineering

Scientists visualize their data and interact with them on computers in order to thoroughly understand them. Nowadays, data become so large and complex that it is impossible to display the entire data on a single image. Scientific visualization often suffers from visual clutter problem because of high spacial resolution/dimension and temporal resolution. Interacting with the visualizations of large data, on the other hand, allows users to dynamically explore different parts of the data and gradually understand all information in the data. Information congestion and visual clutter exist in visualizations of different kinds of data, such as flow field data, tensor field data, and time-varying data. Occlusion presents a major challenge in visualizing 3D flow and tensor fields using streamlines. Displaying too many streamlines creates a dense visualization filled with occluded structures, but displaying too few streams risks losing important features. Glyph as a powerful multivariate visualization technique is used to visualize data through its visual channels. Placing large number of glyphs over the entire 3D space results in occlusion and visual clutter that make the visualization ineffective. To avoid the occlusion in streamline and glyph visualization, we propose a view-dependent interactive 3D lens that removes the occluding streamlines/glyphs by pulling the them aside through animations. High resolution simulations are capable of generating very large vector fields that are expensive to store and analyze. In addition, the noise and/or uncertainty contained in the data often affects the quality of visualization by producing visual clutter that interferes with both the interpretation and identification of important features. Instead, we can store the distributions of many vector orientations and visualize the distributions with 3D glyphs, which largely reduce visual clutter. Empowered by rapid advance of high performance computer architectures and software, it is (open full item for complete abstract)

Committee: Han-Wei Shen (Advisor); Huamin Wang (Committee Member); Arnab Nandi (Committee Member) Subjects: Computer Engineering; Computer Science

Doctor of Philosophy, Case Western Reserve University, 1991, Psychology

Spatial localization is a unique aspect of selective attention which precedes and facilitates other aspects of sensory processing. Despite its importance, the mechanism for the allocation of attention in space is unclear. Theories of spatial attention include spotlight models with variable enlargement of the attentional field, divided attention models with stationary discontinuity, the dynamic focusing model with continuous adjustment, or a scanning model with multiple attentional shifts. Each of these models explains some but not all of the characteristics of spatial attention reported in the literature. These characteristics suggest a new model, the scanning focus model, which is characterized by multiple attentional shifts with variable focal sizes ranging from a large low-resolution attentional field to a small high-resolution one. This project investigated the allocation of spatial attention in a blank field and the scanning focus model using a paradigm independent of peripheral acuity. Six tachistoscopic experiments presented single letters at different locations and under different conditions of attentional allocation. In Experiment I, reaction times were proportionally slower for stimuli occurring in a combination of three regions located at differe nt distances from the fixation point, as compared to stimuli occurring in each region alone. In Experiment II, reaction times were not disproportionately slowed to probe stimuli in an unanticipated region. In Experiments III and IV, reaction times increased with increases in the number of possible stimulus locations within single regions but not within regions in conditions containing more than one region. The pattern of findings for Experiments I-IV were less compatible with the other models of spatial attention than with the scanning focus model proposed here. Furthermore, two final experiments explored the changes in spatial attention in normal elderly and in demented subjects and found changes consistent with (open full item for complete abstract)

Committee: Grover Gilmore (Advisor) Subjects: Psychology, Experimental

Doctor of Philosophy, The Ohio State University, 2013, Vision Science

Bioptic telescopic spectacles (BTS) allow people with vision impairment to obtain driving licensure even when their visual acuity does not meet normal state standards. BTS are spectacles with a small telescope implanted in one or both of the lenses. The telescope is used for brief periods during driving to spot distant targets such as road signs and traffic signals. The study described in this dissertation examines visual and demographic associations among obtaining a bioptic driving license, training and road testing results, and motor vehicle collisions in patients with low vision. The study also compares the collision rate of bioptic drivers to that of a control group of non-bioptic drivers matched on age and sex. A retrospective study of medical records was completed for patients examined for entry into the Ohio bioptic driving program at the College of Optometry at The Ohio State University over a five year period. Data were collected on visual factors, documented driver training, licensure testing results, and post-licensure driving record. No significant associations were found among visual and demographic factors and obtaining licensure after an initial vision examination. Several factors were significantly associated with the amount of training documented for candidates for licensure, including age and previous non-bioptic driving experience. The amount of training documented was associated with road testing results, but not with driving safety after licensure. Previous driving experience was also significantly associated with occurrence of motor vehicle collisions (MVC) in bioptic drivers, with drivers without previous experience having approximately 2.5 times as many collisions per year of licensure than those with previous experience. Other significant associations with MVC in bioptic drivers included age and the number of non-collision related convictions. Nystagmus was independently associated with MVC, but no other patient visual factors w (open full item for complete abstract)

Committee: Thomas Raasch (Advisor) Subjects: Biomedical Research; Health Sciences; Ophthalmology; Optics; Public Health; Public Policy; Transportation