Position Cues and Reward Memories as Compatible Components of Serial Learning

An Attempt at Blocking of Position Learning by Training with Reward-Memory Associations

“…One account (e.g., Capaldi, Alptekin, Miller, & Birmingham, 1997) emphasizes the memories of differing rewards being associated with current and future reward values. Another account (e.g., Burns, Kinney, & Criddle, 2000) stresses cues related to the ordinal position of the rewards, which may be associated with reward values in that location.…”

Retention of Ordinal Position Information with Limited and Extended Serial Training

“…The study of memories, usually of differing reward events, in animal serial learning also has a long history that has produced clear evidence for animals employing reward memories in serial problems; and the understanding of the nature of those memories is now fairly sophisticated (reviewed by Capaldi, 1994). Evidence that animals use information about the position of items in a list is recent, but also clear (Burns, Dunkman, & Detloff, 1999;Burns, Kinney, & Criddle, (2000) ; Burns, Wiley, & Payne, 1986;Chen, Swartz, & Terrace, 1997;Couvillon, Brandon, Woodard, & Bitterman, 1980; D 'Amato & Colombo, 1988, Roiblat, Pologue, & Scopatz, 1983Straub & Terrace, 1981). Our understanding of the nature of position information for animals, however, is not sophisticated.…”

“…In this procedure, the well-established pattern of running fast on the first and third trials and slow on the second trial was retained in all three kinds of series in the transfer tests, a result that shows the influence of learning about position information , but tells us little about the nature of that information. Burns et al (2000) offered several possible sources of information about position that included: intentional or unintentional trial-to-trial variations in running procedures (Burns et aI., 1986), the time (e.g., Church & Broadbent, 1991) from the first trial to each of the remaining trials in the series, the memory of reward outcomes from previous trials (Capaldi, 1994), and the number of previous trials in the series (e.g., Capaldi & Miller, 1988). It may also be that position fashions a linear, cognitive representation (D ' Amato, 1991), which the animal may scan from position to position.…”

“…For example, Burns et al (2000;Experiment 1) found that train ing with PSN, SSN, PPN , and SPN produces equally strong discriminative responding , compared to SPN or PSN, if train ing is continued to 32 days. Furthermore, Burns et al shifted their animals to NNN on Day 33 and found that the rats from both training conditions continued their pattern of approaching the first two trials of the series rapidly while approaching the final trial slowly, even though the reward memories had been changed.…”

“…The present experiment was designed to evaluate a possible reason for the differences in the potency of position cues and reward memories reported by Burns et al (2000) and Capaldi et al (1997) . Although Capaldi et al were not concerned with this discrepancy, as we are here, we borrowed an idea reported by them and attributed to an anonymous reviewer.…”