Study effort and the memory cost of external store availability

Previous work demonstrates that individuals often recall less information if, at study, there is expectation that an external memory store will be available at test. One explanation for this effect is that when individuals can expect access to an external memory store, they forgo intentional, controlled efforts at encoding. The present work offers a novel test of this account by examining study effort, indexed by study time and self-reported strategy use, as a function of instructed external store availability. In two preregistered experiments, participants studied lists of to-be-remembered items for a free recall test and were either instructed that they could use their study list to support them at test or that they could not. Critically, participants controlled their own study time, and no participant had their study list at test, regardless of instruction. Consistent with the effort at encoding account, external store availability influenced both study time and strategy use, and there was evidence that these effects mediated the influence of external store availability on recall performance. Interestingly, much of the memory cost remained when controlling for study effort, thus, suggesting that the cost is potentially multiply determined.