ASA 127th Meeting M.I.T. 1994 June 6-10

3aPP10. Auditory localization in noise. II. The effects of masker location.

Michael D. Good

Dept. of Psychol., Wright State Univ., Dayton, OH 45435

Ford Motor Co., Manufacturing Systems Dept., Dearborn, MI 48124

Robert H. Gilkey

Wright State Univ., Dayton, OH 45435

Wright-Patterson AFB, Dayton, OH 45433-6573

Good and Gilkey [preceding abstract] report that the ability to determine the direction of a masked, broadband, click-train signal in the free-field is dependent on signal-to-noise ratio. In the present study, localization performance was measured at two signal-to-noise ratios as a function of the spatial location of the masker. Subjects judged the direction of the signal, which could emanate from any of 239 possible spatial directions (completely surrounding the subject in azimuth and ranging from -45(degrees) to 90(degrees) in elevation), by pointing at a 20-cm-diam spherical model of auditory space. The masker was at one of five possible spatial locations (front, back, left, right, or above, relative to the subject). In general, the judged direction of the signal was biased toward the location of the masker. However, the strength of this effect depended on the signal-to-noise ratio and on the location of the masker. [Work supported by AFOSR-91-0289.]