Virtual reality potential as a platform to measure listening effort

Virtual reality (VR) is usually used to simulate complex visual scenes with a head-mounted display (HMD). However, VR can also be used to obtain better control over the visual environment and to monitor ocular dynamics during listening experiments. In this study, a low-cost HMD was used to track eye gaze and pupil diameter during a dichotic listening task in a simple virtual environment that simulated a computer display. The pupillometry results from the VR environment were compared to those obtained on the same task with a desktop monitor research-grade eye tracker. Participants recalled digits in the right ear and ignored interfering digits in the left ear. It was hypothesized that greater pupil dilation would be observed for dichotic compared to monotic listening with both HMD and research-grade eye trackers. Preliminary data support this hypothesis. The HMD was also evaluated for its potential to collect eye-tracking data in tablet-based clinical speech-in-noise tasks not originally designed for pupillometry. Results suggest that the task-evoked pupil response can be measured with the HMD on clinical tasks and a VR-based system has potential as a low-cost clinical tool to collect objective measures of listening effort.