Effects of uncertainty on auditory spatial resolution in the horizontal plane

Auditory spatial resolution was measured in the horizontal plane under several conditions of stimulus uncertainty. All tests were conducted in an anechoic chamber. Minimum audible angle (MAA) were slightly but significantly larger in the Azimuth Uncertain condition, indicating that even with a simple stimulus, spatial resolution is better when subjects know where to listen than when they do not know. For cases in which the target is not in front, subjects can benefit from prior knowledge to reduce the amount of informational masking.