Reserpine and the Partial Reinforcement Effect in the Fish Tilapia H. Macrocephala

Abstract

A strong partial reinforcement effect was produced in 20 fish trained to a free operant striking response by injection of reserpine before extinction of the response. This was interpreted as a result of inhibition of responding during extinction of 20 Ss trained on a consistent schedule of reinforcement rather than facilitation of responding in Ss trained on a .4 variable ratio schedule of reinforcement.

Reserpine and conditioned suppression in the fish Tilapia h. macrocephala

“…The characteristic reduction by reserpine of baseline response rate found in rats, monkeys, and guinea pigs was not observed in this fish. This agrees with the results of Waleszek & Abood (1956), in which reserpine reduced aggressive behavior in fighting fish, and also with the results of Haralson & Clement (1968), in which reserpine produced the PRE in the African mouthbreeder, in both instances without noticeable sedation.…”

“…in four Ss and an equal volume of normal saline was injected in two Ss 1 h before the beginning of the test session. This injection procedure and dosage was similar to that described by Haralson & Clement (1968). RESULTS In Fig.…”

“…Keller & Umbreit (1956) have shown that reserpine can eliminate chemically induced behavior effects in several species of fish; Waleszek & Abood (1956) were able to reduce aggression in Siamese fighting fish; and Haralson & Clement (1968) have produced the partial reinforcement effect in the African mouthbreeding fish by administration of reserpine during extinction. In the latter two studies, reserpine produced little or no depression of baseline behavior; this is in marked Psychon.…”