Recognition memory asymmetries predicted by individual item memorability

According to current recognition memory theories, a major source of confusion when people judge which stimuli they remember is the contextual similarity of those stimuli to those from the studied list. However, these theories overlook the potential for confusions to arise from item-intrinsic memorability properties – namely, the likelihood that a stimulus will be correctly recognized if studied (“hittability”) or falsely recognized if not (“false-alarmability”) – independent of contextual similarity. Here, we introduce a memorability continuum model, which predicts that differences in the individual “hittability” and “false-alarmability” of arbitrary items A and B can often lead to asymmetric recognition performance in a forced-choice task such that recognition of target A over foil B is more accurate than recognition of target B over foil A. Our model successfully predicted specific item pair asymmetries that context-based inter-item similarity could not explain, highlighting the need to integrate item-level memorability into existing recognition memory theories.