Sensitivity to interaural intensitive disparities: listeners' use of potential cues

Thresholds for interaural intensitive disparities (IIDs) for a 500-Hz tone were measured in several stimulus conditions including those in which the use of intracranial position as a cue was effectively eliminated by roving the interaural temporal disparity of the stimuli. Removing position as a cue resulted in substantial degradation of sensitivity to IID. The overall patterning of the data suggests that threshold-IIDs measured in standard binaural paradigms that yield fused intracranial images reflect the use of changes in intracranial position. That is, comparisons among the data suggest that listeners' judgments depend upon binaural spatial cues and not on comparisons of the concomitant monaural increments and decrements in level, per se, that inevitably result from the imposition of IIDs.