Pilot Study of Brain Stimulation to Improve Orientation and Mobility in Adults with Visual Field Loss from Retinitis Pigmentosa, Rod-Cone Dystrophy, or Glaucoma

What this Trial Is About

Researchers are evaluating whether non-invasive brain stimulation can improve orientation and mobility skills in adults with constricted visual fields in both eyes, caused by conditions such as retinitis pigmentosa, rod-cone dystrophy, or advanced glaucoma. This pilot randomized, double-blind, placebo-controlled study aims to understand if high-frequency transcranial random noise stimulation hf-tRNS applied to the primary visual cortex can enhance visual processing and reduce crowding effects, potentially aiding mobility. Participants will undergo two stimulation sessions spaced 48 hours apart one with active hf-tRNS and one with placebo sham stimulation, delivered for 20 minutes each while seated quietly. The order of stimulation is randomized and double-blinded. During each session, participants complete a standardized orientation and mobility O&M course with natural and artificial obstacles before stimulation, and again at 2 and 30 minutes afterward. Participants who use a white cane are encouraged to use their own cane during the course. Throughout the study, researchers will assess walking speed, time to complete course sections, and visual detection and identification distances of obstacles. Safety is monitored by trained researchers who accompany participants during the course, with sessions video-recorded for accuracy. The entire study includes three visits one for eligibility confirmation and two for stimulation and assessment. The primary outcome is the percentage preferred walking speed, with secondary outcomes including obstacle detection and identification distances. The study is conducted at the University of Waterloo and aims to inform larger future studies.

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