Sound localization measured by eye-tracking

Objective: To introduce a new method of measuring sound localization ability based on eye-tracking and to test this method by analysing the influence of mild induced conductive hearing loss on sound localization. Design: Sound signals were presented from different angles, and the participant's responses were measured using an eye-tracking device. For validation, a comparison of responses to visual stimuli was performed. To test the clinical application of this method, a mild conductive hearing loss was simulated, and the impact of this change on sound localization was measured. Study sample: Fifteen participants. Results: The system provided repeatable measurements, and there was a good correlation of sound and visual signals. A large number of trials could be completed fairly rapidly. Following the induced conductive hearing loss, a decline of 5.5° in the accuracy of sound localization in the horizontal plane was found towards the side of the non-impaired ear for frontal presentations. Conclusions: Quantifying sound localization by eye-tracking was found to be feasible, fast and accurate. A mild conductive hearing loss caused a slight degradation of sound localization accuracy within the 30° frontal sector, which is in good agreement with results found using methods requiring more extensive instrumentation.