Classical conditioning of an “avoidance” response in goldfish using a linear presentation procedure

The present study examined the nature of the “avoidance” response in goldfish under the linear presentation procedure (Zerbolio, 1981). With this procedure, shuttling behavior occurring during the presentation of the trial stimulus produces either CS? or CS+, and further occurrence of shuttling within the trial interval (10 sec) changes the value of CS from negative to positive, or vice versa. If the fish remains in the compartment when the prevailing cue state is CS? at the end of the interval, shock can be avoided. With this procedure fish responded to the CS+ more than to the CS? and avoided shock. But fish in one of two control groups, in which responses had no effect in changing the cue state from CS+ to CS?, or vice versa, also showed a clear differentiation. The results were generally in line with the view that the “avoidance” response in fish is acquired through classical conditioning. The contribution of classical conditioning to the acquisition of avoidance response is discussed.