AUDITORY STREAM SEGREGATION IN GOLDFISH (CARASSIUS-AURATUS)

Goldfish were classically conditioned to a mixture of two pulse trains differing in both repetition rate and the spectral profile of the pul ses. Animals were then tested for generalization to single pulse train s having one or the other spectral profile presented at a variety of r epetition rates. Generalization functions of repetition rate were qual itatively similar to those obtained following conditioning to either o f the pulse trains alone. Thus, the spectral profile of each pulse typ e was appropriately associated with the repetition rate at which that pulse type was presented during conditioning. These results indicate t hat the two concurrent pulse trains making up the conditioning stimuli were analyzed independently, forming two auditory streams. When eithe r of the two pulse trains were presented with a 500 ms onset asynchron y, stream segregation was enhanced. These and other results suggest th at many fundamental features of the human sense of hearing are widely shared among vertebrate animals, and may have developed first among fi shes. (C) 1998 Published by Elsevier Science B.V. All rights reserved.