Pitch discrimination interference between binaural and monaural or diotic pitches

Fundamental frequency (F0) discrimination between two sequentially presented complex (target) tones can be impaired in the presence of an additional complex tone (the interferer) even when filtered into a remote spectral region [Gockel, H., et al. (2004). J. Acoust. Soc. Am. 116, 1092-1104]. This "pitch discrimination interference" (PDI) is greatest when the interferer and target have similar F0s. The present study measured PDI using monaural or diotic complex-tone interferers and "Huggins pitch" or diotic complex-tone targets. The first experiment showed that listeners hear a "complex Huggins pitch" (CHP), approximately corresponding to F0, when multiple phase transitions at harmonics of (but not at) F0 are present. The accuracy of pitch matches to the CHP was similar to that for an equally loud diotic tone complex presented in noise. The second experiment showed that PDI can occur when the target is a CHP while the interferer is a diotic or monaural complex tone. In a third experiment, similar amounts of PDI were observed for CHP targets and for loudness-matched diotic complex-tone targets. Thus, a conventional complex tone and CHP appear to be processed in common at the stage where PDI occurs.