Pigeons' timing of an arbitrary and a naturalistic auditory stimulus: toneversus cooing

Previous animal research has traditionally used arbitrary stimuli to invest igate timing in a temporal bisection procedure. The current study compared the timing of the duration of an arbitrary, auditory stimulus (a 500-Hz ton e) to the timing of the duration of a naturalistic, auditory stimulus (a pi geon cooing). In the first phase of this study, temporal perception was ass essed by comparing psychophysical functions for the duration of tone and co oing signals. In the first set of tests, the point of subjective equality ( PSE) was significantly lower for the tone than for the cooing stimulus, ind icating that tones were judged longer than equivalent durations of cooing. In the second set of tests, gaps were introduced in the tone signal to matc h those present in the cooing signal, and no significant difference in the PSE for the tone or the cooing signal was found. A repetition of the testin g conducted with gaps removed from the tone signal, failed to replicate the difference in the PSEs for the tone and cooing signals originally obtained . In the second phase of the study, memory for the duration of tone and coo ing was examined, and a choose-long bias was found for both signals. Based on these results, it appears that, for pigeons, there may be no significant differences in either temporal perception or temporal memory for arbitrary , auditory signals and more complex, naturalistic, auditory signals. (C) 20 01 Elsevier Science B.V. All rights reserved.