Transfer of inhibition after serial feature negative discrimination training

Three experiments examined the transfer of inhibition in Pavlovian serial feature negative (A+, X→ A−) discriminations in a conditioned suppression situation with rat subjects. Consistent with our previous report (P. C. Holland & J. Lamarre, Learning and Motivation, 15, 219–243), the feature (X) showed little or no ability to inhibit suppression to another conditioned excitor (B) that had been consistently reinforced. Nor was substantial transfer observed to excitors that had been partially reinforced, or conditioned, extinguished, and then reconditioned. However, X readily inhibited suppression to an excitor that had been trained within another serial feature negative discrimination (B+, Y → B−). These latter data are difficult to reconcile with our previous proposal that inhibitors established with serial procedures act on particular conditioned stimulus-unconditioned stimulus associations. We suggest that serial feature negative discriminations endow both the feature (X) and the excitor (A) with special properties.