AUTHOR=Biebl Bianca , Arcidiacono Elena , Kacianka Severin , Rieger Jochem W. , Bengler Klaus 

TITLE=Opportunities and Limitations of a Gaze-Contingent Display to Simulate Visual Field Loss in Driving Simulator Studies

JOURNAL=Frontiers in Neuroergonomics

VOLUME=Volume 3 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/neuroergonomics/articles/10.3389/fnrgo.2022.916169

DOI=10.3389/fnrgo.2022.916169

ISSN=2673-6195

ABSTRACT=Research on task performance under visual field loss is often limited due to small and heterogenous samples. Simulations of visual impairments hold the potential to account for many of those challenges. Digitally altered pictures, glasses and contact lenses with partial occlusions have been used in the past. One of the most promising methods is the use of a gaze-contingent display that occludes parts of the visual field according to the current gaze position. In this study, the gaze-contingent paradigm was implemented in a static driving simulator to simulate visual field loss and to evaluate parallels in the resulting driving and gaze behavior compared in comparison to patients.
The sample comprised 15 participants without visual impairment. All subjects performed three drives: with full vision, simulated left-sided homonymous hemianopia and simulated right-sided homonymous hemianopiahemianopia, respectively. During each drive, participants drove through an urban environment where they had to maneuver through intersections by crossing straight ahead, turning left, and turning right. 
Subjects reported reduced safety and increased workload levels during simulated visual field loss, which was reflected in a reduced lane position stability and greater absence of large gaze movements. Initial compensatory strategies could be found concerning a dislocated gaze position and distorted fixation ratio towards the blind side, which was more pronounced for right-sided visual field loss. During left-sided visual field loss, participants showed a smaller horizontal range of gaze positions, longer fixation durations and smaller saccadic amplitudes compared to right-sided homonymous hemianopia and, more distinctively, compared to normal vision. 
The results largely mirror reports from driving and visual search tasks under simulated and pathological homonymous hemianopia concerning driving and scanning challenges, initially adopted compensatory strategies, and driving safety. This supports the notion that gaze-contingent displays can be a useful addendum to driving simulator research with visual impairments ifimpairments if the results are interpreted considering methodological limitations and inherent differences to the pathological impairment.