Self-motion illusions from distorted optic flow in multifocal glasses
Yannick Sauer,
Malte Scherff,
Markus Lappe,
Katharina Rifai,
Niklas Stein,
Siegfried Wahl
Affiliations
Yannick Sauer
Institute for Ophthalmic Research, University of Tuebingen, Tuebingen 72076, Germany; Corresponding author
Malte Scherff
Department of Psychology & Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster 48149, Germany; Corresponding author
Markus Lappe
Department of Psychology & Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster 48149, Germany
Katharina Rifai
Institute for Ophthalmic Research, University of Tuebingen, Tuebingen 72076, Germany; Carl Zeiss Vision International GmbH, Aalen 73430, Germany
Niklas Stein
Department of Psychology & Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, University of Muenster, Muenster 48149, Germany
Siegfried Wahl
Institute for Ophthalmic Research, University of Tuebingen, Tuebingen 72076, Germany; Carl Zeiss Vision International GmbH, Aalen 73430, Germany
Summary: Progressive addition lenses (PALs) are ophthalmic lenses to correct presbyopia by providing improvements of near and far vision in different areas of the lens, but distorting the periphery of the wearer's field of view. Distortion-related difficulties reported by PAL wearers include unnatural self-motion perception. Visual self-motion perception is guided by optic flow, the pattern of retinal motion produced by self-motion. We tested the influence of PAL distortions on optic flow-based heading estimation using a model of heading perception and a virtual reality-based psychophysical experiment. The model predicted changes of heading estimation along a vertical axis, depending on visual field size and gaze direction. Consistent with this prediction, participants experienced upwards deviations of self-motion when gaze through the periphery of the lens was simulated, but not for gaze through the center. We conclude that PALs may lead to illusions of self-motion which could be remedied by a careful gaze strategy.
