Interference between processing and storage in working memory : a domain-general mechanism of time-based resource sharing ?

Evie Vergauwe, Pierre Noël Barrouillet
2010
Working memory refers to the set of structures, mechanisms and resources involved in simultaneously processing and maintaining information. The present work addresses the controversial issue of the nature of limited resources supporting these activites in working memory. We have identified two diverging views in working memory literature and propose an integration of both views by proposing a multi-level framework in which a unitary domain-general central level is combined with a more
more » ... y domain-specific peripheral level in working memory. In line with the Time-Based Resource Sharing model, one of the main assumptions of the multi-level framework concerns the existence of a domain-general mechanism of time-based sharing of attentional resources between processing and storage at the central level of working memory. According to this assumption, domain-general time-based resource sharing should result in central interference between concurrent processing and storage activities, regardless of the domain involved. This was tested in two series of experiments reported in Chapter 5 and 6. Central interference between processing and storage was indeed observed, both within and between the different domains of working memory. That is, when processing and storage are performed concurrently, recall performance is determined by the cognitive load involved in concurrent processing, regardless of the domain involved in processing. Upon the demonstration of the importance of time-based resource sharing, we explored the neural bases of the mechanism in a functional magnetic resonance imaging study reported in Chapter 7. Not surprisingly, the brain areas found to be sensitive to the cognitive load involved in concurrent processing were regions typically associated with attentional allocation and task switching. The theoretical implications of the present findings concern both the structure and functioning of working memory. ... Technical and secretarial services of both the University of Geneva and the University of Ghent are thanked for their help. ... My warm thanks also go to my Belgian friends for the rare, but terrific moments we have spent together and for being there when I needed it, despite the distance. ... I owe my loving thanks to my family and family-in-law for their support. A special thank you goes to Jorre for having shared his couch, chips and TV during my stays in Ghent. ... My most special gratitude is due to my husband, Carl: you're the best. Contents Chapter 1 Working memory: One concept, two conceptions ___________________________ 1.1 The concept of working memory _____________________________________ 1.2 Two conceptions of working memory _________________________________ Chapter 2 The WMS conception: On the non-unitary nature of working memory _________ 2.1 Characterizing the peripheral systems of working memory _______________ 2.1.1 The visuo-spatial sketchpad: On its existence _____________________ 2.1.2 The visuo-spatial sketchpad: On its structure and functioning ________ 2.1.3 Conclusion ________________________________________________ 2.2 The central component of working memory ___________________________ 2.2.1 Abandoning implicitly the storage function of the central executive ___ 2.2.2 Abandoning explicitly the storage function of the central executive ___ 2.2.3 Conclusion ________________________________________________ 2.3 The non-unitary nature of working memory: Two distinct views ___________ 2.4 Adding an extra component ________________________________________ 2.5 The WMS tradition: Conclusions ____________________________________ Chapter 3 The WMG conception: On the unitary nature of working memory ____________ 3.1 The resource sharing hypothesis ___________________________________ 3.2 The time-based forgetting hypothesis ________________________________ 3.3 Time-based resource sharing _______________________________________ 3.4 The WMG tradition: Conclusions ____________________________________ Chapter 4 Bridging the gap: two levels of interference in working memory ______________ 4.1 Central and peripheral interference: A multi-level framework _____________ 4.2 The multi-level framework: Accounting for core empirical findings _________ 4.2.1 Selective interference patterns ______________________________ 4.2.2 Processing-storage trade-offs _______________________________ 4.2.3 "Small" dual-task decrements ______________________________ 4.3 Testing the multi-level framework: An overview ________________________ 4.3.1 Hypothesis 1: within-domain resource sharing __________________ 4.3.2 Hypothesis 2: between-domain resource sharing ________________ 4.3.3 Hypothesis 3: time-based nature of resource sharing ____________ 4.3.4 Hypothesis 4: importance of central time-based resource sharing __ 4.3.5 Overview of experiments _________________________________ CONTENTS XXV Chapter 5 Interference between processing and storage in visuo-spatial working memory: Domain-general time-based resource sharing? ____________________________ 5.1 Central interference within the visual and the spatial domains of WM ______ 5.1.1 Central interference within the spatial domain of WM ______________ Experiment 1 _______________________________________________ Experiment 2 ______________________________________________ 5.1.2 Central interference within the visual domain of WM _____________ Experiment 3 ____________________________________________ Experiment 4 ____________________________________________ 5.1.3 Discussion of Experiments 1-4 ________________________________ 5.2 Central interference between the visual and the spatial domains of WM ___ 5.2.1 Central interference between spatial storage and visual processing __ Experiment 5 _____________________________________________ 5.2.2 Central interference between visual storage and spatial processing __ Experiment 6 ____________________________________________ 5.2.3 Discussion of Experiments 5 and 6 _____________________________ 5.3 Time-based nature of central interference in visuo-spatial WM ___________ 5.4 Central interference and selective interference patterns in visuo-spatial WM 5.4.1 Selective interference patterns in complex span tasks ___________ 5.4.2 Selective interference patterns in selective interference tasks ____ Experiment 7 _________________________________________ 5.5 Central interference in visuo-spatial working memory: General discussion __ Chapter 6 Interference between processing and storage: Domain-general time-based resource sharing across verbal and visuo-spatial working memory? __________ 6.1 Central interference within the verbal and the visuo-spatial domains of WM ________________________________________________ 6.1.1 Central interference within the visuo-spatial domain ______________ Experiment 8 ____________________________________________ 6.1.2 Central interference within the verbal domain ___________________ Experiment 9 ________________________________________ 6.1.3 Discussion of Experiments 8 and 9 _____________________________ 6.2 Central interference between the verbal and the visuo-spatial domains ____ 6.2.1 Central interference between visuo-spatial storage and verbal processing _______________________________________ CONTENTS XXVI Experiment 10 ________________________________________ 6.2.2 Central interference between verbal storage and visuo-spatial processing _____________________________________ Experiment 11 _____________________________________________ 6.2.3 Discussion of Experiments 10 and 11 ___________________________ 6.3 Time-based nature of central interference in working memory ___________ 6.4 Central interference and selective interference patterns ________________ 6.4.1 Selective interference patterns in recall performance _____________ 6.4.2 Selective interference patterns in processing performance _________ 6.5 Verbal and visuo-spatial working memory: General discussion ____________ 6.5.1 Central domain-general interference or an incomplete selective interference pattern? _________________ 6.5.2 Central domain-general interference or task-specific effects? _______ 6.5.3 Central domain-general interference or representational overlap? _ 6.5.4 Central domain-general interference or code-/modality-specific effects? ______________________________ 6.5.5 The special case of verbal working memory _____________________ 6.5.6 The nature of resources supporting processing and storage: theoretical implications _____________________________________ Chapter 7 The neural correlates of time-based resource sharing _____________________ Chapter 8 General discussion and conclusions ____________________________________ 8.1 The structure of working memory ___________________________________ 8.2 The functioning of working memory _________________________________ 8.3 Conclusions _____________________________________________________ Preface The ability of storing information, while doing something else, is one of the core abilities of the human mind. By making it possible for human beings to perceive and encode, to learn about, to act in and to reflect on the world, it allows the organism to flexibly adapt to an ever-changing environment. Within psychological science, 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. The concept of working memory refers to a set of structures, mechanisms and resources that are involved in simultaneously processing and maintaining information and was introduced by Baddeley and Hitch (1974). Although, as its name implies, the concept of working memory should be thought of as some form of memory, the appropriate emphasis should be on working, for it is conceived as a memory working in the service of complex cognitive behaviour such as planning, organizing, imagery, learning, reasoning, mental rotation, arithmetic, problem solving, abstraction, reading and comprehension. By providing a pivotal interface between perception and memory, and
doi:10.13097/archive-ouverte/unige:9841 fatcat:h3cflucfjrfknp3xmzn7punxau