The effect of perceptual weighting of binaural cues on perceived location

This project investigated how interaural timing and level differences (ITDs and ILDs, respectively) can affect the perceived location of a sound when either one cue was at zero degrees azimuth (midline) and the other was not, or when they both were at non-zero azimuthal locations. Six subjects, including one with severe to profound hearing loss, participated in this study. Several cue combinations were tested, including conditions in which one cue was fixed (at either 30, 60, or 90 degrees) and the other was varied to be between 0 and 60 away from the fixed cue. It was hypothesized that non-zero cues would be weighted more heavily when the other cue was located at zero; whereas, when both cues were at non-zero locations it was hypothesized that both cues would be weighted more evenly, especially when they lie on either side of midline, in which case it was hypothesized that the perceived location would be between the cues presented. Results showed that both the normal hearing listeners and the listener with severe hearing loss have similar patterns. The results ultimately did not support all hypotheses, and different patterns were seen when comparing the three main conditions wherein the reference cue was located at 30, 60, or 90 degrees azimuth