The effects of stimulus frequency on subsequent recall of backward associates

Previous research has shown that increased Thorndike-Lorge frequency (F) of stimulus-terms leads to poorer paired-associate learning (PAL), while increased F-level of response-terms facilitates PAL. Therefore, if a word pair is learned in the order A-B, then later tested in reverse (B-A), there are two possibilities. (1) Error level could be the same on the reverse test, implying that performance on the A-B learning trials determined the strength of the B-A association. (2) Error level on the reverse test could revert to what it would have been if the B-A pair had been learned originally. In the present study the experimental group learned A-B word pairs and was tested on corresponding B-A versions. Results showed that, for the experimental group, the relationship between errors and F-level of the A-terms shifted dramatically between the last A-B trial and B-A test trial. On the B-A test trial, this group performed in a manner comparable to that of a control group trained on B-A throughout. Thus, for pairs which differed in F-level of their stimulus-terms, relative performance during the A-B learning trials was not a crucial factor in later B-A performance.