| Abstract: | Conducted 3 experiments in which 4 groups of female hooded rats (N = 192) were given 35 classical fear-conditioning trials in 1 side of a 2-compartment box. Ss were then allowed to jump a hurdle to the adjacent box and escape the fear-eliciting stimuli. Reward magnitude (fear reduction) during hurdle jumping for 2 groups was either large or small throughout while for 2 groups it was increased or decreased after some training. Manipulated and nonmanipulated reward varied between experiments. Preshift performance was better with large than with small reward. Positive contrast effects were not found, but a negative contrast effect was obtained in Exp. III. The concepts of incentive motivation and frustration, used to account for performance in appetitively motivated learning tasks, are applied to the findings. (27 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) |
