Nicholas I. Hill
C. J. Darwin
Lab. of Exptl. Psychol., Univ. of Sussex, Brighton BN1 9QG, UK
The effect of onset asynchrony and mistuning on the binaural processing of multi-tone stimuli was investigated using a paradigm derived from that of Trahiotis and Stern [C. Trahiotis and R. M. Stern, J. Acoust. Soc. Am. 86, 1285--1293 (1989)]. A tonal complex comprising harmonics 2 to 8 of 100 Hz and presented with an IDT of 1.5 ms gave rise to a single image lateralized towards the ear receiving the leading signal. However, when the central 500-Hz component was delayed by 40 ms relative to the flanking tones, it was heard out as a separate tone shifted towards the opposite side of the head. Similar effects were observed when the 500-Hz component was mistuned from the flanking complex, with shifts of (plus or minus)3% being sufficient for the mistuned component to be lateralized in the vicinity of the mid-line. The results demonstrate that both onset asynchrony and mistuning influence which frequency components IDT information is integrated across. [Work supported by UK SERC and MRC.]