Auditory Discrimination between Compressions and Rarefactions by Goldfish

Abstract

Goldfish were taught to discriminate between a given click and the same click inverted, that is, with the compression and rarefaction phases reversed. The responses were true auditory responses involving the sacculus but not the lateral line. The responses were independent of both waveform (frequency) and intensity and could be elicited with single clicks. Phase was the relevant parameter. Tail flips were found to send a rarefaction wave (rarefaction is the first deflexion) forward from the fish and a compression wave backward. It is proposed that phase analysis of tail-flip sounds is used to tell whether a swimming fish is approaching or receding.