title: Three layers of working memory: Focus-switch costs and retrieval dynamics as revealed by theN-count task.
abstract: Two experiments explored the process of switching items in and out of the focus of attention using a new paradigm, theNcount task (adapted from Garavan, 1998;Nvaried from 1 to 4). This task yielded a focus size of one, indicated by a substantial focus switch cost for 2 count. Additionally, the focus switch costs in response time increased with working memory load, indicating an effortful search process occurring at a speed of about 240 ms/item. Maintaining and switching to and from a passive load did not increase the focus switch costs or decrease memory accuracy, indicating that there is no crosstalk between passive and active items. The results support a concentric theory of working memory: a small focus at its core, a surrounding area of (at least) three readily available items referred to as the outer store, and a still wider region of passive storage, possibly more long term memory than working memory.
authors.affiliation: Beckman Institute, Urbana/Champaign, IL, USA.
authors.forename: Chandramallika
authors.initials: C
authors.lastname: Basak
authors.affiliation: Georgia Institute of Technology, Atlanta, GA, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Verhaeghen
keywords: Ageing; Focus of attention; Focus switching; Retrieval; Working memory
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