Stimulus Control of Information Processing in Rat Short-Term Memory
Douglas S. Grant
University of Alberta

Rats were trained initially on a delayed alternation task in which a forced run to one arm of a T- maze was followed by a free-choice test run. A correct choice was defined as a turn in the direction opposite that to which the rat had been forced. Following acquisition, all trials were cued, with a click-rate-illumination-level compound, as to whether a free-choice test would (remember-cued) or would not (forget-cued) occur. In the first two experiments, forced runs were forget-cued either during (Experiment 1) or after (Experiment 2) the forcing, and memory for the direction of the forcing was tested occasionally. In the final two experiments, animals were forced to each arm prior to the free-choice test run, and an alternation with respect to the second forcing was defined as correct. On different trials, either the first or second forcing was forget-cued. Each experiment revealed evidence of reduced memory for forget-cued forcings. It was concluded that presentation of a forget cue influences information processing in the rat by affecting processes of either maintenance rehearsal or tagging.