Forgetting our facts: the role of inhibitory processes in the loss of propositional knowledge

Seven experiments are reported that show that retrieving facts from long-term memory is accomplished, in part, by inhibitory processes that suppress interfering facts. When asked to repeatedly retrieve a recently learned proposition (e.g., recalling The actor is looking at the tulip, given cues such as Actor looking t__), subjects experienced a recall deficit for related facts (e.g., The actor is looking at the violin) on a recall test administered 15 min later. Importantly, this retrieval-induced forgetting was shown to generalize to other facts in which the inhibited concepts took part (e.g., The teacher is lifting the violin), replicating a finding observed by M. C. Anderson and B. A. Spellman (1995) with categorical stimuli. These findings suggest a critical role for suppression in models of propositional retrieval and implicate the mere retrieval of what we know as a source of forgetting of factual knowledge.