The following is a summary of “A gaze-contingent saccadic re-referencing training with simulated central vision loss,” published in the January 2023 issue of Ophthalmology by Ganesan, et al.
To make up for the visual loss at the fovea, patients with central vision loss (CVL) select an eccentric retinal site for fixation, known as a preferred retinal location (PRL). Saccadic re-referencing to a PRL occurs gradually, despite the fact that most CVL patients may quickly use a PRL instead of the fovea. Saccades place the target in the scotoma without reference. It causes compensatory saccades and ineffective visual exploration. For a study, researchers tried out a technique for teaching saccadic re-referencing.
Healthy people underwent gaze-contingent visual search tasks with simulated central scotomas, requiring them to fixate on targets at a forced retinal location (FRL) determined by investigators. In experiment 1, over the course of five training sessions, they contrasted single-target search and foraging search tasks.
Results showed that both tasks increased gaze sequence efficiency and induced saccadic re-referencing to the FRL. In trial 2, participants underwent substantial training over the course of 25 sessions, both with and without a gaze-contingent FRL marker visible. Observers’ performance eventually resembled that of foveal vision after significant training. Thus, in patients with central vision loss, gaze-contingent FRL fixation is useful for saccadic re-referencing training.
Reference: jov.arvojournals.org/article.aspx?articleid=2785301