Long-term recognition latencies under rehearsal-controlled conditions: Do list-length effects depend on active memory?

Previous studies have found small but consistent effects of list length on recognition latencies for items from supraspan target lists. This result has been interpreted as demonstrating an effect of set size on retrieval from inactive memory. It is possible, however, that such list-length effects may instead be partly or entirely due to a diminishing probability of retrieval from active memory as supraspan list length increases. To test this hypothesis, an experiment with 18 members of a university community was performed in which rehearsal was or was not prevented by means of a counting task. Rehearsal had an effect on recognition latencies that was partly, but not entirely, eliminated by 15 sec of backward counting. Rehearsal-preventing activity did not diminish set-size effects, thus demonstrating that such effects cannot be solely due to active memory. The obtained pattern of results is consistent with a modified version of the model of R. C. Atkinson and J. F. Juola (1973, 1974). (15 ref)