Reduced relational and item-specific processing in cognitive offloading

In many circumstances in everyday life, individuals offload information to external stores (e.g., shopping lists) to compensate for limitations in internal memory. When saving information externally, individuals tend to refrain from actively encoding an additional internal copy of the information, leading to a weakening of its internal trace. This study examined whether the loss of the internal trace due to offloading is limited to item-specific information (e.g., apples, milk) or extends to relational information as well (e.g., fruit, dairy products). In the first two blocks of each of two experiments, participants learned lists of 20 unrelated words, which they could save externally for use during a subsequent memory test. In the third block, participants learned a categorized list consisting of 6 exemplars from 8 semantic categories. While participants could save the list externally, they were prevented access to the list at test. Half of the participants were informed that the list would be unavailable at test, thus relying on internal memory, whereas the remaining participants trusted the list availability. Reliance on the external store led to a reduction in the internal trace of the offloaded information. Notably, saving the information externally resulted in decreased internal memory for both item-specific and relational information. This study indicates that internal memory for relational information does not effectively support the retrieval of information from external stores, and suggests that optimal organization of external stores should highlight relational information.