Abstract
People with bilateral central vision loss affecting the fovea often adopt compensatory viewing strategies that involve the use of the peripheral retina. In some cases, individuals develop a new point of oculomotor reference called a preferred retinal locus (PRL) that is used like a pseudo-fovea for fixating and planning saccadic eye movements. Reduced visual acuity and impaired control of eye movements to peripheral targets make learning to use a PRL for everyday tasks such as reading and locating objects of interest in the environment a challenge. Much of the current research focuses on improving fixation stability at the PRL. How individuals learn to effectively use a PRL is not fully understood, in particular, the relationship between learning to have a stable peripheral fixation and plan saccades using an eccentric target have not been well described. Here we address this question, describing how eye movements change as a person learns to adopt an eccentric retinal locus. Using a gaze contingent eye tracking system and simulated central scotoma, 40 participants were trained to use a PRL for an oculomotor and visual recognition task. After 12 training sessions, measurable improvements were observed in six eye movement metrics. Importantly, we examined the stability of fixation of a target as well as the dispersion of the landing location of saccades. These measures explained a great deal of across-subject variance in accuracy. Fixation stability and saccadic precision were strongly positively correlated. While there was no statistically significant difference in rate of learning, individuals did tend to learn saccadic precision faster than fixation stability. Saccadic precision was also more associated with accuracy for the behavioral task. This suggests that effective intervention strategies should address both fixation stability and saccadic precision.