Where you didn't look: Perimetry based on the analysis of free-viewing gaze behavior while watching movie clips

Free-viewing perimetry is a continuous psychophysical paradigm that aims to assess visual field defects (VFD) while relying solely on an analysis of recorded gaze. Such an approach could benefit patients who cannot be assessed using standard automated perimetry. Previous research has demonstrated that gaze behavior during the free viewing of movie clips contains information on the integrity of the visual field. Yet, thus far, no single analytical approach could reconstruct all types of (simulated) VFD. In the current study, we take a distinctive analytical approach towards VFD reconstruction by explicitly taking into account events that were not gazed at, rather than primarily focussing on those that were. To demonstrate the potential of this approach, we re-analyzed previously recorded data from a gaze-contingent simulated VFD experiment. We compared a participant's gaze behavior to that of control participants while they watched different movie clips. In our analysis, we give specific weight to the events that were prioritized by the control participants, yet missed out upon by those with simulated defects. Our findings indicate that this approach allows us to reliably detect the presence of, and to varying degrees reconstruct five types of simulated visual field defects. We conclude that free-viewing perimetry is feasible and may form the foundation for an inclusive complement to standard automated perimetry.