Remote measurement of spectral weighting in sound localization using virtual reality headsets.

Unequal weighting of binaural information across frequency can reduce sensitivity in the presence of competing but uninformative cues ("binaural interference"), a potentially serious problem for listeners who use combined electric and acoustic (EAS) hearing. Here, we used virtual-reality techniques to measure spectral weighting functions (SWF) during localization of simulated EAS stimuli [see van Ginkel et al., 2019, JASA 145, 2445-52]: low-frequency "acoustic" noise bands and high-frequency "electric" click trains. This study was conducted remotely at each participants' location, using sanitized and calibrated research equipment (Oculus Quest 2 headsets and Sennheiser HD 280 Pro headphones) delivered by lab personnel. Sounds were presented with random binaural-cue jitter across seven components on each trial. SWFs were computed by statistical regression of localization responses onto binaural cue values. SWFs confirmed the dominance of 400-1000 Hz components reported previously [Folkerts and Stecker 2022, JASA 151:3409-25]. Introducing a gap between noise and click-train components increased weight on neighboring components, consistent with reduced interference in such conditions [van Ginkel et al., 2019]. Finally, presenting noises and click trains from competing locations reduced weight on non-target components for most but not all participants, a potential marker of susceptibility to binaural interference.