The Sternberg paradigm is one in which subjects see a relatively small list of items and then are presented with a single item and have to judge whether that item is from the list. As the result was originally described and is still described in many textbooks, the claim is that there is a linear relationship between the number of items in the memory set and time to make this judgment. In fact the relationship is more typically curvilinear and extends out to lists as long as 20 items in length (Briggs, 1974). Data illustrating this relationship was reported in Burrows and Okada (1975).

Since Burrows and Okada do not report the details of presentation timing or practice, we simulated in ACT-R only the recognition judgment task and not the study. For this recognition judgment task we used a model similar to the model of sentence recognition in studies of the fan effect. This kind of model seems appropriate for time-pressured recognition judgments.

ACT-R Model