Theory of binaural interaction based on auditory-nerve data. IV. A model for subjective lateral position

Abstract

A model for the subjective lateral position of 500‐Hz tones is presented and compared with experimental lateralization data. Previous papers in this series have explicitly described the auditory‐nerve response to these stimuli and proposed a binaural displayer that interaurally compares the auditory‐nerve firing times. The outputs of the displayer are postulated to represent the only information about detailed firing times that is available to the brain. In the present paper, lateral‐position predictions are obtained by a central nonoptimal weighting of these outputs that depends on the interaural intensity difference of the tone. These predictions describe the results of lateralization‐matching experiments more accurately and over a wider range of stimulus conditions than previous theories, except for those results which suggest that low‐frequency binauraltones can generate multiple perceptual images. The predictions of our model are also consistent with the results of centering and laterality‐comparison experiments. It is argued that the data discussed in this paper are generally incompatible with theories that propose a peripheral interaction of interaural timing and intensity information such as the latency hypothesis.