Evaluating mechanisms of proactive facilitation in cued recall

Confusion of older information with newer, similar information is a potent source of memory errors. The current project focused on understanding how memories for recent experiences interact, or interfere, with other related information. In the experiments, participants study multiple lists of pairs of items. Items from an initial study list (e.g., A-B) reappear on a second study list paired with new, other items (e.g., A-Br). Memory performance for A-Br pairs is contrasted with control pairs exclusive to the second study list (e.g., C-D). We observed that the correct recall of the second presentation of a target (Br) is better when cued by its partner (A) despite being studied with a different partner during the initial presentation; a phenomena called proactive facilitation. We examined multiple possible explanations for proactive facilitation, including whether proactive facilitation was driven by changes in response threshold, whether participants encoded the pairs with repeated items and associations better during the second study list, or whether participants spent more time searching memory for A-Br pairs. In general, the data appear to be most consistent with the idea that some items, when encountered a second time, are encoded more completely while others are not. Implications for models of memory are discussed.