The role of working memory in mental arithmetic.

We review the evidence for the 3 principal theoretical contenders that vie to explain why and how working memory (WM) capacity is limited. We examine the possibility that capacity limitations arise from temporal decay; we examine whether they might reflect a limitation in cognitive resources; and we ask whether capacity might be limited because of mutual interference of representations in WM. We evaluate each hypothesis against a common set of findings reflecting the capacity limit: The set-size effect and its modulation by domain-specificity and heterogeneity of the memory set; the effects of unfilled retention intervals and of distractor processing in the retention interval; and the pattern of correlates of WM tests. We conclude that-at least for verbal memoranda-a decay explanation is untenable. A resource-based view remains tenable but has difficulty accommodating several findings. The interference approach has its own set of difficulties but accounts best for the set of findings, and therefore, appears to present the most promising approach for future development. (PsycINFO Database Record

/pdf/what-limits-working-memory-capacity-1g3fnhgqs6.pdf

What limits working memory capacity

The ability to store and later use information is essential for a variety of adaptive behaviors, including integration, learning, generalization, prediction and inference. In this Review, we survey theoretical principles that can allow the brain to construct persistent states for memory. We identify requirements that a memory system must satisfy and analyze existing models and hypothesized biological substrates in light of these requirements. We also highlight open questions, theoretical puzzles and problems shared with computer science and information theory.

https://clm.utexas.edu/fietelab/Papers/Rishi_memoryreview_NN_2016.pdf

Computational principles of memory

Any mature field of research in psychology—such as short-term/working memory—is characterized by a wealth of empirical findings. It is currently unrealistic to expect a theory to explain them all; theorists must satisfice with explaining a subset of findings. The aim of the present article is to make the choice of that subset less arbitrary and idiosyncratic than is current practice. We propose criteria for identifying benchmark findings that every theory in a field should be able to explain: Benchmarks should be reproducible, generalize across materials and methodological variations, and be theoretically informative. We propose a set of benchmarks for theories and computational models of short-term and working memory. The benchmarks are described in as theory-neutral a way as possible, so that they can serve as empirical common ground for competing theoretical approaches. Benchmarks are rated on three levels according to their priority for explanation. Selection and ratings of the benchmarks is based on consensus among the authors, who jointly represent a broad range of theoretical perspectives on working memory, and they are supported by a survey among other experts on working memory. The article is accompanied by a web page providing an open forum for discussion and for submitting proposals for new benchmarks; and a repository for reference data sets for each benchmark. (PsycINFO Database Record (c) 2018 APA, all rights reserved)

/pdf/benchmarks-for-models-of-short-term-and-working-memory-4dxqy5x8di.pdf

Benchmarks for models of short-term and working memory.

About number sense

Although forgetting in the short term is a ubiquitous phenomenon, its exact causes remain undecided. The aim of the present study was to test the temporal decay hypothesis according to which memory traces fade away with time when attention is diverted by concurrent activities. In two experiments involving complex span tasks, adults were asked to remember series of items (either letters or spatial locations) while verifying multiplications. The duration of processing was manipulated by presenting multiplications either in word (three    ×    four    =    twelve) or digit (3    ×    4    =    12) format, the former taking longer to solve, while the time available to restore memory traces after each operation was kept constant across conditions. In line with the temporal decay hypothesis, the longer solution times elicited by solving word multiplications resulted in poorer recall performance. The fact that longer processing times had a comparable effect on both verbal and visuospatial memory and that the difference between conditions remained stable from the first to the last trials makes it difficult to account for these findings by assuming that forgetting is exclusively due to representation-based interference or buildup of proactive interference.

/pdf/time-causes-forgetting-from-working-memory-3tidzhzzj2.pdf

Time causes forgetting from working memory.

The present study evaluated the socio-emotional development of very preterm born infants at 12 months corrected age. Forty-one infants born very preterm (<29 weeks of gestation) were compared to 22 infants born full term on a standardized behavioral assessment and a parental temperament questionnaire, both measuring emotional reactivity to joy, anger and fear, as well as sustained attention. The behavioral assessment showed that very preterm infants exhibited as much joy as full term infants during a joy-eliciting episode. However, they expressed a significantly higher reactivity in anger-eliciting situations and a reduced reactivity toward fear-eliciting situations. For all three emotion-eliciting situations, the preterm infants reacted with a higher level of motor activity. The preterm infants also exhibited a distinct attention pattern with a significantly higher initial attention level which declined rapidly throughout the episode. The questionnaire did not show any group differences. The clinical relevance of these results in terms of preliminary hallmarks of later behavioral difficulties such attention deficit/hyperactivity disorder are discussed as well as the inconsistencies observed between the questionnaire and the behavioral assessment.

Emotional reactivity at 12 months in very preterm infants born at <29 weeks of gestation.

The present study addresses the existence of a central pool of domain-general resources in working memory. For this purpose, we examined interference between processing and storage activities involving information pertaining to different domain (verbal vs. visuo-spatial) while explicitly minimising representation-based interference at the peripheral level of working memory. Experiment 1 required maintenance of auditorily presented letters for further oral recall while concurrently judging visually presented spatial configurations by pressing keys. Experiment 2 required maintenance of visually presented random locations for further manual recall while concurrently judging auditorily presented words by giving oral responses. In both experiments, the cognitive load of processing was manipulated, a manipulation that clearly affected recall performance. This suggests strongly that working memory comprises a pool of domain-general attentional resources at the central level.

/pdf/evidence-for-a-central-pool-of-general-resources-in-working-pu63wut3e3.pdf

Evidence for a central pool of general resources in working memory

https://archive-ouverte.unige.ch/unige:98067/ATTACHMENT01

Attentional refreshing of information in working memory: Increased immediate accessibility of just-refreshed representations☆

The episodic buffer has been described as a structure of working memory capable of maintaining multimodal information in an integrated format. Although the role of the episodic buffer in binding features into objects has received considerable attention, several of its characteristics have remained rather underexplored. This is the case for its maintenance capacity limits and its separability from domain-specific maintenance buffers. The present study addressed these questions, making use of a complex span paradigm in which participants were asked to maintain cross-domain (i.e., verbal–spatial) associations. The 1st experiment showed that the capacity limit for these cross-domain associations proved to be lower than the capacity limit for single features, and did not exceed 3. Cross-domain associations and single features depended, however, to the same extent on attentional resources for their maintenance. The 2nd experiment showed that domain-specific (verbal or spatial) resources were not involved in the maintenance of cross-domain information, revealing a clear distinction between the episodic buffer and the domain-specific buffers. Overall, in line with the episodic buffer hypothesis, these findings support the existence of a central system of limited capacity for the maintenance of cross-domain information.

/pdf/the-maintenance-of-cross-domain-associations-in-the-episodic-r5luicayez.pdf

Naomi Langerock

Papers

Time causes forgetting from working memory.

Emotional reactivity at 12 months in very preterm infants born at <29 weeks of gestation.

Evidence for a central pool of general resources in working memory

Attentional refreshing of information in working memory: Increased immediate accessibility of just-refreshed representations☆

The maintenance of cross-domain associations in the episodic buffer.