A gaze-contingent saccadic re-referencing training with simulated central vision loss

Area of Science:

• Neuroscience
• Ophthalmology
• Visual Science

Background:

• Central vision loss (CVL) necessitates using a preferred retinal location (PRL) for fixation, bypassing the fovea.
• Saccadic re-referencing to a PRL is slow, causing inefficient visual exploration due to corrective saccades into the scotoma.

Purpose of the Study:

• To evaluate a novel gaze-contingent method for training saccadic re-referencing in individuals with simulated central vision loss.
• To assess the effectiveness of different visual search tasks and training durations on improving saccadic re-referencing.

Main Methods:

• Healthy participants performed gaze-contingent visual search tasks with a simulated central scotoma, using a forced retinal location (FRL) for fixation.
• Experiment 1 compared single-target and foraging search tasks over five sessions.
• Experiment 2 involved extensive training (25 sessions) with and without a visible FRL marker.

Main Results:

• Both single-target and foraging search tasks improved gaze efficiency and induced saccadic re-referencing to the FRL.
• Extensive training, particularly with a visible FRL marker, allowed participants' performance to approach that of normal foveal vision.

Conclusions:

• Gaze-contingent forced retinal location (FRL) fixation is a promising training tool for saccadic re-referencing.
• This method can significantly enhance visual exploration efficiency in patients experiencing central vision loss.