Mcnab F, Klingberg T. Prefrontal cortex and basal ganglia control access to working memory. Nat Neurosci 11: 103-107

Developmental Cognitive Neuroscience, Stockholm Brain Institute, Karolinska Institutet, MR Centrum, Stockholm, Sweden.
Nature Neuroscience (Impact Factor: 16.1). 02/2008; 11(1):103-7. DOI: 10.1038/nn2024
Source: PubMed


Our capacity to store information in working memory might be determined by the degree to which only relevant information is remembered. The question remains as to how this selection of relevant items to be remembered is accomplished. Here we show that activity in the prefrontal cortex and basal ganglia preceded the filtering of irrelevant information and that activity, particularly in the globus pallidus, predicted the extent to which only relevant information is stored. The preceding frontal and basal ganglia activity were also associated with inter-individual differences in working memory capacity. These findings reveal a mechanism by which frontal and basal ganglia activity exerts attentional control over access to working memory storage in the parietal cortex in humans, and makes an important contribution to inter-individual differences in working memory capacity.

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    • "In addition to examining the effects of tDCS on T2 identification, we looked at how tDCS affects the ability to inhibit irrelevant distractors. Distractor inhibition appears to play an important role in the AB (Arnell & Stubitz, 2010; Olivers & Meeter, 2008; Di Lollo et al., 2005; Chun & Potter, 1995), and evidence suggests that left DPLFC may be particularly involved in situations in which target information has to be maintained in WM in the face of distraction (Feredoes et al., 2011; McNab & Klingberg, 2008; Postle, 2006). It is thus possible that any observed stimulation-induced modulations of the AB reflect a changed ability to inhibit distracting information. "
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    • "These findings provide clear evidence that instructional manipulations can influence estimated VWM capacity. Along with the substantial evidence that individual differences in filtering ability explain a significant proportion of the acrosssubject variation in k̂ max (Cowan & Morey, 2006; McNab & Klingberg, 2008), the present study makes it clear that performance in simple VWM tasks can be influenced by factors other than the amount of representational medium (whether conceived as a set of fixed-resolution slots or a flexible pool of resources). Thus, studies of individual differences in estimated VWM capacity must be careful about assuming that they have measured the amount of representational medium (i.e., that k̂ max is actually a good estimate of K max ). "
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