On the origin of functional differences in recollective experience

Abstract

Subjects studied target words that were repeated either immediately (lag0) or after six intervening items (lag6). At retention testing, subjects were required to discriminate targets from distractors and, contingent on a 'yes' response, to classify each identified item as one that evoked either a 'remember' (R) response or a 'know' (K) response. An R response indicated recognition based on conscious recollection, and K, recognition without conscious recollection. R responses were significantly greater in lag6 than lag0 whereas the reverse was found for K responses. The data are interpreted as showing that R responses depend on the probability of a target stimulus engaging conscious effortful processing, whereas K responses are increased in the absence of conscious involvement at learning.