Associative recognition and the list strength paradigm

When a subset of list items is strengthened, the discriminability of the nonstrengthened items is unaffected. This regularity has been dubbed the null list strength effect (LSE), and despite its many replications in item recognition, little research has investigated whether an LSE occurs in associative recognition. We conducted two experiments in which a set of pairs were studied once and a set of interference pairs were studied either once (pure-weak-list condition) or four times (mixed-list condition). Equivalent levels of performance for the nonstrengthened pairs were observed in both the pure-weak and mixed conditions using both yes-no and two-alternative forced choice testing. Additionally, equivalent false alarm rates were observed between rearranged pairs composed of weak and strong items. Both sets of results were found to be consistent with a matrix model that has no overlap among its item representations.