Training With Simulated Scotoma Leads to Behavioral Improvements Through at Least Two Distinct Mechanisms

Abstract

Purpose Individuals with central vision loss due to macular degeneration (MD) often spontaneously develop a preferred retinal locus (PRL) outside the area of retinal damage, which they use instead of the fovea. Those who develop a stable PRL are more successful at coping with their vision loss. However, it is unclear whether improvements in visual performance at the PRL are specific to that retinal location or are also observed in other parts of the retina. Perceptual learning literature suggests that the retinal specificity of these effects provides insight about the mechanisms involved. Better understanding of these mechanisms is necessary for the next generation of interventions and improved patient outcomes. Methods To address this, we trained participants with healthy vision to develop a trained retinal locus (TRL), analogous to the PRL in patients. We trained 24 participants on a visual search task using a gaze-contingent display to simulate a central scotoma. Results Results showed retinotopically specific improvements in visual crowding only at the TRL; however, visual acuity improved in both the TRL and in an untrained retinal locus. Conclusions These results suggest that training with an artificial scotoma involves multiple mechanistic levels, some location-specific and some not, and that simulated scotoma training paradigms likely influence multiple mechanisms simultaneously. Eye movement analysis suggests that the non-retinotopic learning effects may be related to improvements in the capability to maintain a stable gaze during stimulus presentation. This work suggests that effective interventions promoting peripheral viewing may influence multiple mechanisms simultaneously.

Comparison of stereopsis thresholds measured with conventional methods and a new eye tracking method

“…They aid researchers in investigating the pathophysiology of various eye conditions (e.g., amblyopia, strabismus) and their effects on vision by furnishing detailed data on eye movement patterns and gaze behavior [ 33 ]. Moreover, eye trackers can be employed to evaluate the efficacy of treatments and interventions by comparing changes in eye movement patterns pre- and post-therapy or procedures [ 34 ]. In sum, eye trackers contribute to ophthalmology research, fostering the development of innovative diagnostic techniques and novel treatments for an extensive range of eye conditions.…”