ASYMMETRIC PERFORMANCES IN MONAURAL LOCALIZATION OF SOUND IN-SPACE

Ten subjects localized a 3.5-kHz high-pass noise originating in the median sagittal plane (MSP)-a plane along which location judgments are highly dependent on spectral cues. Three different experimental conditions were established: (1)binaural listening, (2) monaural listening with the left ear, and (3)monaural listening with the right ear. All subjects performed best when listening binaurally. In comparison with the right ear,location judgments of source elevation was significantly more accurate when listening with the left ear (P = 0.048). Also. perceived displacement from midline, a common occurrence when listening monaurally, was less when localizing with the left ear (P = 0.059). These data, in conjunction with the animal literature demonstrating that auditory cortex contralateral to the ear stimulated is essential for accurate localization, suggest that the right hemisphere is better in processing complex spectral information.