Explaining category interference effects in associative memory.

Two studies with 220 undergraduates investigated the effects of categorization on the acquisition and long-term retention of AB word pairs using modeling techniques that factor the contributions of various storage and retrieval factors. In Exp I, each S memorized 1 of the 4 basic types of lists: unrelated cues/unrelated targets, categorized cues/unrelated cues, unrelated cues/categorized targets, and categorized cues/categorized targets. Ss in Exp II memorized 24-item AB lists to criterion. Acquisition data showed that there was a crossover interaction such that the effects of increasing the degree of cue or target relatedness depended on the nature of the comparison items. In contrast with the results of previous studies, the effects were larger when categorization was manipulated on the target side of AB pairs than when it was manipulated on the cue side. The degree of categorization affected retrieval difficulty but not storage difficulty. Long-term retention data indicated that, contrary to the acquisition data, the effects of categorization on retention were uniformly positive. Categorization decreased the amount of forgetting primarily by reducing the rate at which traces were lost from memory (storage failure) during the retention interval. Results are discussed in terms of modern unitary-trace theories of associative memory. (French abstract) (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)