Different definitions of the nonrecollection-based response option(s) change how people use the “remember” response in the remember/know paradigm

In the remember/know paradigm, a “know” response can be defined to participants as a high-confidence state of certainty or as a low-confidence state based on a feeling of familiarity. To examine the effects of definition on use of responses, in two experiments, definitions of “remember” and “guess” were kept constant, but definitions of “know” and/or “familiar” were systematically varied to emphasize (a) a subjective experience of high confidence without recollection, (b) a feeling of familiarity, (c) both of these subjective experiences combined within one response option, or (d) both of these experiences as separate response options. The confidence expressed in “know” and/or “familiar” definitions affected how participants used response options. Importantly, this included use of the “remember” response, which tended to be used more frequently when the nonrecollection-based middle response option emphasized a feeling of familiarity rather than an experience of “just knowing.” The influence of the definitions on response patterns was greater for items that had undergone deep rather than shallow processing, and was greater when deep-encoded and shallow-encoded items were mixed, rather than blocked, at test. Our findings fit with previous research suggesting that the mnemonic traces underlying subjective judgments are continuous and that the remember/know paradigm is not a pure measure of underlying processes. Findings also emphasize the importance of researchers publishing the exact definitions they have used to enable accurate comparisons across studies.