A two-process account of long-term serial position effects

Four experiments with 60 undergraduates found long-term serial position effects in the delayed free recall of word pairs whose presentations were separated by distractor activity. The long-term primacy effect was reduced by manipulations discouraging cumulative rehearsal of the first few pairs, such as increasing the difficulty of the distractor task in the interpair interval (Exp I) and incidental learning instructions (Exp II). The long-term recency effect was not changed by either of these manipulations. It was also unaffected by the difficulty of the distractor task in the retention interval. Results are inconsistent with a short-term store interpretation of the long-term recency effect. Recency was positively correlated with the ratio of the length of the interpair interval to the length of the retention interval. Based on these results, it was hypothesized that the primacy effect was due to extra processing given to the first few items, and recency was due to a retrieval strategy that relied on contextual-temporal cues available at the recall test. This hypothesis was tested and its predictions confirmed in Exp IV. (14 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved).