Role of reward magnitude and incomplete reduction of reward magnitude in the frustration effect.

Abstract
Thirty naive food-deprived (22-hr.) male rats received 72 acquisition and 96 postshift trials in an L-shaped double-alley apparatus. In acquisition 16 Ss (Group 10) received 10 45-mg. pellets in the 1st goal box (G1) on each trial, while 14 Ss (Group 2) received 2 pellets in G1. In every block of 6 postshift trials, Group 2 received 2 pellets in G1 on 3 trials and no reward on 3 trials, while Group 10 received 10 pellets on 3 trials, 2 pellets on 1 trial, and no reward on 2 trials. Both groups always received 2 pellets in the 2nd goal box. Final postshift speeds were inversely related to absolute (postshift) G1 reward magnitude, but unrelated to excepted (acquisition) reward magnitude.