Long-term discriminated avoidance performance in the rat.

Abstract

3 experiments are reported in each of which 8 albino rats were trained on a simple discriminated avoidance problem with illumination change as CS and bar pressing as the instrumental response. In all experiments 50-87% of Ss failed to develop avoidance responding, even though, in Experiment 2, training continued for 4 mo and totaled 7,330 trials. Neither adrenalin injections nor extinction sessions improved avoidance performance, and variation in the direction of the illumination change that constituted the CS was also without noticeable effect.