Abstract:

Relative weights given to interaural differences of time (IDTs) of source and echo clicks were computed for a range of echo delays (1--256 ms) for stimuli presented over headphones. On each trial, source and echo IDTs were selected randomly and independently ((mu)=0 (mu)s, (sigma)=100 (mu)s). Listeners were instructed to indicate the direction of the IDT, left or right, of the source or echo (in separate conditions). Weights were obtained by computing the correlation between the source or echo IDT and the listener's binary responses. In all conditions, little weight was given to the echo at short echo delays (<8 ms), but the echo was given weight equal to or greater than that of the source at intermediate echo delays (8--32 ms). For echo delays >32 ms, listeners gave greater weight to the source or echo, as appropriate. For all echo delays, when listeners were instructed to indicate the direction of the source IDT, the percent correct was lower when the echo DT varied across trials than when it was fixed at 0 (mu)s, indicating that the binaural information of the echo was not completely suppressed in any condition. [Work supported by NIH, NIDCD, and AFOSR.]