Clinical Research Directory

Brain Stimulation Effects on Orientation and Mobility Skills in Adults With Vision Impairment

This pilot clinical trial evaluates whether non-invasive brain stimulation improves the orientation and mobility (O\&M) skills of individuals with constricted visual fields in both eyes. The study is composed of three visits. The first visit is meant to confirm eligibility by performing a few clinical tests. Eligible participants will then complete two additional visits, one in which the participants receive active stimulation, and one in which the participants receive placebo (sham) stimulation. Stimulation will be administered in a randomized, double-blind order. To evaluate improvement, various measures of O\&M performance will be assessed on a standardized obstacle course featuring static natural and artificial obstacles at defined intervals after the intervention. We hypothesize that the application of hf-tRNS to V1 will improve the orientation and mobility skills of individuals with constricted visual fields immediately following stimulation as a results of enhanced periphery through modulation of the mechanisms responsible for crowding, thereby reducing crowding effects and improving contrast for individuals with rod-cone dystrophy and RP (genetic conditions), whereas for individuals with glaucoma (a neurogenerative condition), any improvement noted would be attributed to be enhanced processing of visual signal in the affected periphery. The results will inform the design of a future, larger-scale study.

Virtual Reality-Base Intelligent Orientation and Mobility Specialists Trial

The human subject research is a randomized, controlled training trial that tests the effectiveness of three Virtual Reality-based Intelligent Orientation and Mobility Specialists (VR-IOMSs) in teaching orientation and mobility (O\&M) task skills to low vision patients. It will be conducted on two sites, University of Alabama at Birmingham (UAB) and Alabama Institute for Deaf and Blind (AIDB). The same protocol will be used on both sites. UAB will be the sIRB for the trial. Three O\&M tasks will be studied, timing to cross a signalized street using the near lane parallel traffic surge skill, timing to cross an uncontrolled street using the traffic gap judgment skill and learning outdoor numbering system. A VR-IOMS will be develop for each task. The training does not involve research subjects walking into street traffic. Low vision subjects who have difficulties with these O\&M tasks due to their impaired vision will be randomized into three groups, learning the task from a VR-IOMS (experimental group), from a human Certified Orientation \& Mobility Specialist (COMS) in real streets (active control group) and not learning the task but spending the same amount of time watching low vision education videos (placebo group). All subjects will be evaluated by COMSs in real streets around the two study sites before training (pre-training), within 3 days after the completion of training (post-training) and 3 months after the completion of training (follow up). Their ability to perform the O\&M tasks will be assess quantitatively using objective methods. COMSs who conduct these evaluations will be blinded for subject training assignment. The primary outcome measure is the training effect, the difference in task performance between the pre-training and post-training real street evaluations. The training effects of the 3 groups will be compared to determine the training effectiveness of the VR-IOMS relative to human COMS. Secondary outcome measures include the retainment of the training effect. Objective assessment of the VR-IOMS training process and trainee subjective evaluation of the VR-IOMS training will also be analyzed.