The limited capacity of working memory plays a central role in determining individual differences and age-related changes in cognitive abilities. Our understanding of working memory rests on theories describing components and mechanisms verbally, often lacking the precision necessary to make testable predictions. This state contrasts with the related literature of short-term memory, which has generated a number of computational models of how people recall short lists in order (e.g., Burgess & Hitch, 1999). My colleagues and I have started to build on the insights gained from modelling short-term memory tasks to develop computational models of working memory. Our initial focus is on the complex-span paradigm, in which people are asked to recall a short list in order, and to complete an unrelated processing task in between presentation of the list items (e.g., reading span, operation span). I will present two computational models that both reproduce key data with the complex-span paradigm. One model extends the SOB model of Farrell and Lewandowsky (Farrell & Lewandowsky, 2002), the other is a computational implementation of the time-based resource-sharing model (Barrouillet, Bernardin, & Camos, 2004). I will show where the models make different predictions, and if time allows, present some data helping to distinguish them.
Barrouillet, P., Bernardin, S., & Camos, V. (2004). Time constraints and resource sharing in adults' working memory spans. Journal of Experimental Psychology: General, 133, 83-100.
Burgess, N., & Hitch, G. J. (1999). Memory for serial order: A network model of the phonological loop and its timing. Psychological Review, 106, 551-581.
Farrell, S., & Lewandowsky, S. (2002). An endogenous distributed model of ordering in serial recall. Psychonomic Bulletin & Review, 9, 59-79.