PERCEPTION OF SPECTRALLY AND TEMPORALLY COMPLEX SOUNDS BY THE GOLDFISH (CARASSIUS-AURATUS)

Behavioral studies on complex sound perception in goldfish were carrie d out in order to help determine what, if any, differences exist betwe en the sense of hearing of fishes and other vertebrates. A stimulus ge neralization paradigm was used with classical conditioning in three ex periments to determine: (1) the perceptual relations between a pure to ne and harmonic complexes having a fundamental frequency equal to that of the tone; (2) the combined effects on perception of pulse repetiti on rate and spectral envelope; and (3) whether goldfish can be shown t o identify a complex source when presented simultaneously with another complex source. Experiment 1 showed that the perceptions of tones and harmonic complexes differ profoundly even for the cases in which they have common periodicities and frequency components. Experiment 2 demo nstrated that pulse repetition rate and spectral location simultaneous ly control behavior, and that repetition rate exerts behavioral contro l independent of spectral location. Experiment 3 indicates that goldfi sh did not 'hear out' or analyze a complex target source within a mixt ure of complex sources. In general, goldfish appear to be aware of mul tiple acoustic dimensions of complex sounds, suggesting both pitch-lik e and timbre-like perceptual dimensions. These results do not permit a qualitative distinction between the sense of hearing of goldfish and that of other vertebrates.