Directional hearing is only weakly dependent on the rise time of acoustic stimuli

First-spike latency differences between left and right auditory-nerve fiber s have been proposed as one of the physiological cues for sound localizatio n. Since first-spike latency depends not only on stimulus intensity, but al so on the steepness of the amplitude rise of a sound stimulus, differences in first-spike latency are not a simple function of interaural level differ ences but also a function of stimulus rise time. We therefore investigated whether rise time influences human directional hearing in a localization pa radigm. Subjects tended to localize a 3-kHz tone pulse with a long (18-ms) rise time further to the side than one with a short (2-ms) rise time delive red from the same source. The small size of this effect and its large inter -individual variability, however, suggest that it is of minor importance fo r human directional hearing, (C) 2000 Acoustical Society of America. [S0001 -4966(00)01902-0].