Comparing the accuracy of monotic and dichotic repetition pitch

Abstract

When white noise is added to its delayed replica, a pitch is evoked corresponding to the reciprocal value of the delay time (T). When the delayed replica is fed to the same ear, the pitch (monotic repetition pitch: MRP) is rather salient; when, instead, it is fed to the contralateral ear, the pitch (dichotic repetition pitch: DRP) is rather faint. MRP is readily explained by spectral information processing in the cochlea. For reasons of parsimony, DRP is assumed to be the result of central spectrum processing preceded by interaural (temporal) processing. The present paper reports measurements on the accuracy of pitch matching for both MRP and DRP. Because of the difference in saliency, a difference in accuracy might be expected, if pitch saliency and pitch accuracy would be positively correlated. It turned out that pitch accuracy, expressed as the relative standard deviation, is dependent on the delay time and the stimulus type. For T larger than about 20 ms (the infra pitch range) the accuracy is about 10% for both MRP and DRP. For T smaller than 20 ms (the pitch range), accuracy is about 0.5% for MRP and 3% for DRP.