Analysis of Central Mechanism in Visual Discrimination Learning of Goldfish

Abstract

In an attempt to clarify the neural mechanism of visual discrimination learning in fish, a series of six experiments, four behavioral and two electrophysiological, were performed in goldfish. In the behavioral studies retention of color discrimination was tested following lesions of various brain structures, and in the electrophysiological studies the effects of conditioning stimulations or ablations of different brain structures upon the evoked response in the optic tectum induced by the test stimulation of the contralateral optic disk were investigated. The results obtained suggest that goldfish has a quite characteristic visual mechanism different from those in higher vertebrates. An outline of that distinctive feature in fish was drawn.