Dual Processes in Recognition Memory: The Opposing Influences of Processing-Ease on Recognition Memory Decisions

Abstract

A key finding in recognition memory experiments is that difficult to process stimuli are often remembered better than easy to process stimuli. In the present study, processing difficulty was manipulated by presenting participants with interleaved word pairs which were either congruent (perceptually fluent) or incongruent (perceptually disfluent). In a reanalysis of datasets from several prior studies, we found that recognition sensitivity (d’) was greater for incongruent items. However, this benefit in d’ for incongruent items was not reflected in the hit rates for responses in the two slowest response time quartiles; here we found equivalent hit rates for congruent and incongruent items. We propose that a dual process account can explain this pattern of equivalent hit rates. While there is one process at study which leads to better memory for incongruent items, there is another process at test that affects bias rather than sensitivity. Specifically, items at test which were perceptually fluent lead to an illusion of memory, where participants mistook the ease of processing these items with prior experience. In a following empirical study, by manipulating processing fluency at study separately from processing fluency at test, we investigated the contribution of each of these processes to recognition memory decisions. The results offered strong evidence for this dual process account.