Domain-general involvement of the posterior frontolateral cortex in time-based resource-sharing in working memory: An fMRI study

Abstract

Working memory is often defined in cognitive psychology as a system devoted to the simultaneous processing and maintenance of information. In line with the time-based resource-sharing model of working memory (TBRS; Barrouillet and Camos, 2015;Barrouillet et al., 2004), there is accumulating evidence that, when memory items have to be maintained while performing a concurrent activity, memory performance depends on the cognitive load of this activity, independently of the domain involved. The present study used fMRI to identify regions in the brain that are sensitive to variations in cognitive load in a domain-general way. More precisely, we aimed at identifying brain areas that activate during maintenance of memory items as a direct function of the cognitive load induced by both verbal and spatial concurrent tasks. Results show that the right IFJ and bilateral SPL/IPS are the only areas showing an increased involvement as cognitive load increases and do so in a domain general manner. When correlating the fMRI signal with the approximated cognitive load as defined by the TBRS model, it was shown that the main focus of the cognitive load-related activation is located in the right IFJ. The present findings indicate that the IFJ makes domain-general contributions to time-based resource-sharing in working memory and allowed us to generate the novel hypothesis by which the IFJ might be the neural basis for the process of rapid switching. We argue that the IFJ might be a crucial part of a central attentional bottleneck in the brain because of its inability to upload more than one task rule at once. © 2015 Elsevier Inc. All rights reserved. IntroductionThe ability of storing information, while doing something else, is one of the core abilities of the human mind making it possible for humans to flexibly adapt to an ever-changing environment. In cognitive psychology, the limited-capacity system underpinning human's ability to mentally maintain information in an active and accessible state, while concurrently and selectively processing some additional information, is referred to as working memory (WM; Baddeley and Hitch, 1974). A model of WM that has focused explicitly on the dual functioning of WM, i.e., the combination of processing and storage, is the time-based resource-sharing model (TBRS; Barrouillet et al., 2004Barrouillet et al., , 2007Barrouillet et al., , 2011. According to this model, the dual functioning of WM is achieved through a mechanism of time-based sharing of domain-general resources between processing and storage. The model assumes that processing and storage both require attention which constitutes a pool of limited domain-general resources that needs to be shared (see also Egner, 2014a, 2014b, for a similar assumption). When attention is focused on the memory traces of to-be-recalled information, they receive activation, but this activation decays over time as soon as the focus of attention is switched away (Cowan, 1995(Cowan, , 1999Towse and Hitch, 1995). Their complete loss would be avoided by a rap...

Benchmarks for models of short-term and working memory.

“…While the cognitive-load effect has mainly appeared in serial recall tasks such as complex span tasks (Barrouillet et al, 2004(Barrouillet et al, , 2007(Barrouillet et al, , 2011Vergauwe et al, 2009Vergauwe et al, , 2010Vergauwe et al, , 2012 and Brown-Peterson tasks (Liefooghe et al, 2008), it has also been obtained in single-item recall or local recognition tests (Ricker & Cowan, 2010;Vergauwe et al, 2009;Vergauwe, Hartstra, Barrouillet, & Brass, 2015) and change detection tasks (Vergauwe et al, 2014). was estimated by the ratio of total processing time on the parity or location judgments (i.e., the sum of response times) to total time (i.e., the sum of the time intervals for each judgment).…”

Short-term memory for spatial, sequential and duration information

“…STM of an item has been thought to remain stable for as long as attention is sustained. Elapsing time has often been considered responsible for the decay of information over a retention interval, with evidence supporting models based on rehearsal [ 41 ], or drift [ 42 ] and extinction [ 43 ] in neural representations. Against this, it has been shown that memory decay can be reduced if the gap between trials (when nothing is happening) is much longer than the retention interval [ 44 ].…”

Dual-process theories and consciousness: the case for ‘Type Zero’ cognition: Table 1.

“…The effect of increasing cognitive load also has a different neural signature. Cognitive load in general modulates the activity of superior parietal lobule and intraparietal sulcus bilaterally, and particularly of the right inferior frontal junction ( Vergauwe et al. 2015 ).…”