Blocking despite changes in reinforcer identity：（阻塞尽管强化物的身份的变化）.pdfVIP

Animal Learning Behavior 1994, 22 (4), 442-457 Blocking despite changes in reinforcer identity BEN A. WILLIAMS University of California, San Diego, La Jolla, California Rats were trained on a discriminated operant barpressing task according to a standard blocking design. In some conditions, the reinforcer was changed between the pretraining and compound con- ditioning phases; for other conditions, the reinforcer remained the same across phases. In three sep- arate experiments using both between- and within-subject designs, strong blocking effects occurred regardless of the change in the reinforcer. In a fourth experiment, a multiple schedule of reinforce- ment was used in which response-independent reinforcers were superimposed on the schedule of re- sponse-contingent reinforcers. The degree of response suppression caused by the free reinforcer was greater when the free reinforcers were the same as the response-contingent reinforcers than when they were different. The role played by the reinforcer identity in contingency experiments thus ap- pears to be different from the role it plays in blocking experiments. Conditioning to one element (B) of a compound stim- mines when blocking and unblocking will occur if “sur- ulus (AB) is often blocked if the other element of that prise” is not the appropriate explanatory framework? compound (A) has previously been paired with the rein- Ganesan and Pearce (1988) have recently reported forcer (Kamin, 1968). Blocking may fail to occur, how- failures to disrupt blocking that appear to cause sub- ever, when the reinforcer is changed between the initial stantial