Learning a 720-Item Paired-Associate List by a Part Method: Effect of List Length on Learning Time Per Item

20 Ss learned a 720-item paired-associate list by the progressive parts method, using a self-paced procedure. The items simulated those of a mail-distribution scheme learned by mail sorters. The stimuli were verbal and/or numerical while all responses were two-digit numbers. Learning was carried to 95% criterion. The mean time required to learn 20 new items each session showed a definite learning-to-learn effect over the 36 sessions. The cumulative total study time was a perfect linear function of the number of items learned. Thus, the mean total time required to learn each item (102 sec.) was independent of the number of items learned.

Over-All List Facilitation and the von Restorff Effect with Nonnoxious Isolation Stimuli

To demonstrate list facilitation with nonnoxious stimuli, this study used 5 unique nonnoxious stimuli as isolates randomly distributed in a paired-associate list. Lists of 20 identical low-association word-pairs were presented in 3 groups: (1) Control—all 20 pairs in standard format, (2) Control—all 20 in changed format, and (3) Experimental—5 pairs in changed format randomly distributed among 20. 18 male college students (6 per group) received 4 standard PA acquisition trials. Statistically significant findings were: (1) experimental exceeded controls in total list performance, (2) format-changed items (isolates) exceeded control counterparts, (3) standard stimuli in experimental lists exceeded control counterparts, and (4) items immediately preceding and following isolates exceeded others (spread-of-isolation effect). The results were interpreted in terms of OR theory.

S-R Similarity: Effect of Location and Predictability of Repeated Units

Ease of learning a paired-associate list increases with the predictability of an intra-pair repeated unit. In addition, the pattern of errors, (e.g., percentage of omissions), made by S changes as the predictability of the repeated unit changes. Finally, the combination of S and R locations used to repeat the unit has an effect with the combination S1-Ra being less effective than the other combinations in aiding performance.

Acquired Word Value and Verbal Learning

This experiment tested the hypothesis that pairing nonsense syllables with pleasant photographs would make them more learnable subsequently than would pairing them with indifferent photographs. Ss were shown syllable-photograph pairs and instructed to learn their own labels for the photographs as responses to the syllables. Half the photographs were “very pleasant” and half were “indifferent.” Next, the same syllables were made responses to 2-digit numbers in a second paired-associate list. The pleasant photographs were learned faster in Phase 1 and the pleasantly-paired syllables were learned faster in Phase 2. The superiority of the latter syllables was based partly upon greater availability at the end of Phase 1 but partly upon some independent learning effect during Phase 2. This superiority was hypothesized to be the result of greater implicit rehearsal of the pleasantly-paired syllables.

Mediation and Forgetting

An experiment was performed to test the hypothesis that the presence of mediation can reduce verbal forgetting. During original learning experimental groups acquired two classes of multiple mediators that intervened between the stimulus and response members of a paired-associate list (A-C). An AB-BC-AC paradigm was used for experimental groups. Control groups did not have the mediators and simply learned the A-C list. All groups recalled the A-C list after either three or seven days. There were 20 Ss in each group. Experimental groups were not found superior to control groups in recall, as hypothesized. One type of mediation actually produced retention inferior to that of control groups. Some implications for mediation, the interference hypothesis of forgetting, and amount recalled, were discussed.

Learning and Performance in a Verbal Paired-Associate Task with Preschool Children

The aims of the present investigation were to explore the hypothesis that a short anticipation interval in verbal paired-associate learning affects performance rather than learning and to design a procedure suitable for preschool-aged children. One group of Ss received practice on a paired-associate list with a short anticipation interval while another group learned the same list with a longer anticipation interval. When the interval of the former group was increased, they performed as well as the latter group. The results suggest that the number of trials administered in a verbal paired-associate task is a better measure of learning than S's level of performance.