The effects of two temporal cues on pitch judgments

A series of experiments required listeners to judge which of two sequentially presented pulse trains, bandpass filtered to contain only unresolved harmonics, had the higher pitch. The effects of two temporal cues were explored. The ''common interval'' cue refers to the fact that the interval between any two pulses in each train is an integer multiple of 1/F0, where F0 is the period of the pulse train. The ''mean rate'' cue arises from the fact that the number of pulses in any period of time is proportional to F0. It was manipulated, independently of the common interval cue, by removing a proportion of the pulses in each of two trains with different F0s. The mean rate cue was removed in one condition of the experiments by deleting more pulses in the stimulus with the higher F0; in other conditions, the number of pulses deleted was either independent of F0, or was higher for the stimulus with the lower F0. The results both of forced-choice and of pitch-matching experiments showed that pitch judgments were affected by the mean rate cue, even though, at least when only a few pulses were deleted, listeners could make consistent judgments using only the common interval cue. Performance in all conditions deteriorated when the number of pulses to be deleted was increased, or when a masking pulse train with a similar spectrum to the targets was mixed with them. Under such circumstances, performance in the absence of the mean rate cue was close to chance. (C) 1997 Acoustical Society of America.