Editing Serial-position effect (section)

===Single-store models===

According to single-store theories, a single mechanism is responsible for serial-position effects. A first type of model is based on relative temporal distinctiveness, in which the time lag between the study of each list item and the test determines the relative competitiveness of an item’s memory trace at retrieval.<ref name="Bjork 1974"/><ref>{{cite journal | last1 = Neath | first1 = I. | last2 = Knoedler | first2 = A. J. | year = 1994 | title = Distinctiveness and serial position effects in recognition and sentence processing | journal = Journal of Memory and Language | volume = 33 | issue = 6| pages = 776–795 | doi=10.1006/jmla.1994.1037}}</ref> In this model, end-of-list items are thought to be more distinct, and hence more easily retrieved.

Another type of model is based on contextual variability, which postulates that retrieval of items from memory is cued not only based on one’s mental representation of the study item itself, but also of the study context.<ref>{{cite journal | last1 = Howard | first1 = M. W. | last2 = Kahana | first2 = M. | year = 1999 | title = Contextual variability and serial position effects in free recall | journal = Journal of Experimental Psychology: Learning, Memory, and Cognition | volume = 24 | issue = 4| pages = 923–941 | doi=10.1037/0278-7393.25.4.923| pmid = 10439501 | citeseerx = 10.1.1.360.18 }}</ref><ref>{{cite journal | last1 = Howard | first1 = M. W. | last2 = Kahana | first2 = M. J. | year = 2002 | title = A distributed representation of temporal context | journal = Journal of Mathematical Psychology | volume = 46 | issue = 3| pages = 269–299 | doi=10.1006/jmps.2001.1388}}</ref> Since context varies and increasingly changes with time, on an immediate free-recall test, when memory items compete for retrieval, more recently studied items will have more similar encoding contexts to the test context, and are more likely to be recalled.

Outside immediate free recall, these models can also predict the presence or absence of the recency effect in delayed free recall and continual-distractor free-recall conditions. Under delayed recall conditions, the test context would have drifted away with increasing retention interval, leading to attenuated recency effect. Under continual distractor recall conditions, while increased interpresentation intervals reduce the similarities between study context and test context, the relative similarities among items remains unchanged. As long as the recall process is competitive, recent items will win out, so a recency effect is observed.