Article

Basic operations in working memory: Contributions from functional imaging studies

Institute of Medical Psychology, Goethe University, Heinrich-Hoffmann-Strasse 10, D-60528 Frankfurt am Main, Germany.
Behavioural brain research (Impact Factor: 3.03). 12/2010; 214(2):172-9. DOI: 10.1016/j.bbr.2010.05.041
Source: PubMed

ABSTRACT

Working memory (WM) constitutes a fundamental aspect of human cognition. It refers to the ability to keep information active for further use, while allowing it to be prioritized, modified and protected from interference. Much research has addressed the storage function of WM, however, its 'working' aspect still remains underspecified. Many operations that work on the contents of WM do not appear specific to WM. The present review focuses on those operations that we consider "basic" because they operate in the service of memory itself, by providing its basic functionality of retaining information active, in a stable yet flexible way. Based on current process models of WM we review five strands of research: (1) mnemonic selection of one item amongst others, (2) updating the focus of attention with the selected item, (3) updating the content of visual WM with new item(s), (4) rehearsal of visuospatial information and (5) coping with interference. We discuss the neuronal substrates underlying those operations obtained with functional magnetic resonance imaging and relate them to findings on "executive functions". The presented data support the view that WM emerges from interactions between higher sensory, attentional and mnemonic functions, with separable neural bases. However, interference processing and the representation of rule switching in WM may demand an extension of the current WM models by executive control functions.

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Available from: Christoph Bledowski
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    • "Functional neuroimaging studies have found activations of the superior frontal sulcus, posterior cingulate cortex, precuneus, posterior parietal cortex, and dorsolateral prefrontal cortex (DLPFC) and it is likely that distinct brain regions are involved in the different types of operation. The DLPFC seems to be prevalently involved in selection operations (Bledowski et al., 2010). WM can be explored using delayed recognition or recall tasks. "
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