Editing Serial-position effect (section)

===Dual-store models===
These models postulate that study items listed last are retrieved from a highly accessible short-term buffer, i.e. the [[Short-term memory|short-term store]] (STS) in human [[memory]]. This allows items that are recently studied to have an advantage over those that were studied earlier, as earlier study items have to be retrieved with greater effort from one’s [[Long-term memory|long-term memory store]] (LTS).

An important prediction of such models is that the presentation of a distraction, for example solving [[Arithmetic|arithmetic problems]] for 10–30 seconds, during the retention period (the time between list presentation and test) attenuates the recency effect. Since the STS has limited capacity, the distraction displaces later study list items from the STS so that at test, these items can only be retrieved from the LTS, and have lost their earlier advantage of being more easily retrieved from the short-term buffer. As such, dual-store models successfully account for both the recency effect in immediate recall tasks, and the attenuation of such an effect in the delayed free recall task.

A major problem with this model, however, is that it cannot predict the long-term recency effect observed in delayed recall, when a distraction intervenes between each study item during the [[interstimulus interval]] (continuous distractor task).<ref name="Bjork 1974">Bjork & Whitten (1974). ''Recency sensitive retrieval processes in long-term free recall'', Cognitive Psychology, 6, 173–189.</ref> Since the distraction is still present after the last study item, it should displace the study item from STS such that the recency effect is attenuated. The existence of this long-term recency effect thus raises the possibility that immediate and long-term recency effects share a common mechanism.<ref>{{cite journal | last1 = Greene | first1 = R. L. | year = 1986 | title = Sources of recency effects in free recall | journal = Psychological Bulletin | volume = 99 | issue = 12| pages = 221–228 | doi=10.1037/0033-2909.99.2.221}}</ref>