Context effects in the lateralization of sine tones?

Low‐frequency sine tones can have large interaural time differences, but high‐frequency tones cannot. If listeners estimate the lateral positions of tones of different frequency, using a fixed lateralization response scale, the estimates may depend on the experimental blocking of the tones. A context where all frequencies appear equally often (mixed) serves as a standard. It was hypothesized that a context with tones blocked on frequency would lead to abnormally large lateral position estimates for high‐frequency tones because of a tendency to use the entire response scale in any stimulus‐range context. Four listeners estimated the lateral positions of sine tones with frequencies 200, 500, 750, and 1,000 Hz having all possible interaural phase differences (IPD) spaced by 30 deg. Fixed‐frequency blocks were done first, then mixed. Very little trace of the hypothesized effect was observed, either in the overall range of responses or in the slope of the response‐IPD function for small IPD values. The same listeners matched the laterality of the same tones using the interaural level difference (ILD) of a narrow noise band. Relative slopes of the ILD‐IPD functions agreed with slopes of the lateral position estimates. [Work supported by the NIDCD.]