The interdependence of pitch and temporal judgments by absolute pitch possessors

The auditory tau and the kappa effects show that there is time-pitch interdependence in our perception. Our judgments of pitch separation between two tones depend on the temporal interval between them (the auditory tau effect), and our judgments of the tones' temporal interval depend on their pitch separation (the kappa effect). The mechanisms underlying this interdependence were investigated by studying the auditory tau and the kappa effect in three experiments. Comparisons were made between results obtained from subjects with absolute pitch and those who did not have absolute pitch, and two frequency ranges of pure tones (octave and whole-tone conditions) were selected. The procedures had been used in previous experiments (Shigeno, 1986), in which the auditory tau and the kappa effects were compared in speech and nonspeech stimuli. The present results demonstrate that the auditory tau effect does not occur when possessors of absolute pitch judge the closeness of stimuli in pitch, except when the stimulus continuum consists of tones that do not correspond to musical notes in the whole-tone condition. The kappa effect was obtained in the judgment of possessors of absolute pitch in both the octave and the whole-tone conditions. These findings suggest that the interaction between temporal interval and pitch judgment might be explained in terms of the two different memory modes for retaining the pitch of tones, and that these effects occur at the precategorical level.