Analytic listening by the goldfish.

A stimulus generalization paradigm was used with classical respiratory conditioning to study analytic listening in the goldfish. Animals were first conditioned to suppress respiration upon the presentation of a long-duration complex sound comprised of two sinusoidal components, 166 and 724 Hz. Conditioned animals were then presented with a set of eight novel test tones with frequencies between 95 and 1514 Hz, and including 166 and 724 Hz. Response magnitudes were greatest at the frequencies of the components making up the complex to which the animals were initially conditioned. This is a demonstration that the goldfish had acquired independent information about the frequencies of the individual sinusoidal components making up a complex sound, and thus had listened to the complex analytically. To my knowledge, this is the first demonstration of simultaneous frequency analysis and analytic listening by a nonhuman animal, and suggests that this fundamental aspect of human hearing may be a primitive character shared with the fishes and perhaps with all living vertebrates.