The impact of reference tones on the adjustment of interaural cues

In the time-intensity trading paradigm, trading ratios are inconsistent in that they differ as a function of which cue is to be adjusted by the listener. Two explanations have been offered: First, the regression model assumes a regression to the interaural parameters of a reference tone played in alternation with the test tone to cause the phenomenon of inconsistent trading ratios. The second explanation is based on an inflated perceptual weighting of the to-be-adjusted cue. The perceptual-weight explanation has been supported by experimental results showing that the phenomenon of inconsistent trading ratios appears even in the absence of a reference tone. Those findings render regression as the sole explanation for inconsistent trading ratios implausible. The experiments presented in this paper address the question whether regression to the parameters of a reference tone plays a role if a reference tone is presented. Three experiments were conducted in which trials with and without reference tone were compared directly. Both within- and between-subject comparisons showed that a reference tone affects trading ratios and location judgments if present. Although regression cannot be the sole explanation for the phenomenon of inconsistent trading ratios it seems to play a role if a reference tone is presented.