A dual-process account of the list-length and strength-based mirror effects in recognition

Manipulating either list length (e.g., few vs. many study items) or encoding strength (e.g., one presentation vs. multiple presentations of each study item) produces a recognition mirror effect. A formal dual-process theory of recognition memory that accounts for the wordfrequency mirror effect is extended to account for the list-length and strength-based mirror effects. According to this theory, the hit portions of these mirror effects result from differential ease of recollection-based recognition, and the false alarm portions result from differential reliance on familiarity-based recognition. This account yields predictions for participants’ Remember and Know responses as a function of list length and encoding strength. Empirical data and model fits from four experiments support these predictions. The data also demonstrate a reliable list-length effect when several potential confounding factors are controlled, contributing to the debate regarding the effect of list length on recognition.