The temporary nature of number-space interactions

It is commonly accepted that the mental representation and processing of numbers and of space are tightly linked. This is evident from studies that have shown relations between math ability and visuospatial skill. Also, math instruction and education rely strongly on visuospatial tools and strategies. The dominant explanation for these number—space interactions is that the mental representation of numbers takes the form of a mental number line with numbers positioned in ascending order according to our reading habits. A long-standing debate is whether the link between numbers and space can be considered as evidence for a spatial number representation in long-term semantic memory, or whether this spatial frame is a temporary representation that emerges in working memory (WM) during task execution. We summarise our recent work that suggests basic number processing tasks do not operate on a long-term spatial memory representation, but on a representation constructed in serial order WM, where the elements are spatially coded as a function of their ordinal position in the memorised sequence. Implications for a new theoretical framework linking serial order WM and basic number processing are discussed

How does working memory enable number-induced spatial biases?

Number-space associations are a robust observation, but their underlying mechanisms remain debated. Two major accounts have been identified. First, spatial codes may constitute an intrinsic part of number representations stored in the brain – a perspective most commonly referred to as the Mental Number Line account. Second, spatial codes may be generated at the level of working memory when number (or other) representations are coordinated in function of a specific task. The aim of the current paper is twofold. First, whereas a pure Mental Number Line account cannot capture the complexity of observations reported in the literature, we here explore if and how a pure working memory account can suffice. Second, we make explicit (more than in our earlier work) the potential building blocks of such a working memory account, thereby providing clear and concrete foci for empirical efforts to test the feasibility of the account

Turning the mind’s eye inward: the interplay between selective attention and working memory

Historically, cognitive sciences have considered selective attention and working memory as largely separated cognitive functions. That is, selective attention as a concept is typically reserved for the processes that allow for the prioritization of specific sensory input, while working memory entails more central structures for maintaining (and operating on) temporary mental representations. However, over the last decades various observations have been reported that question such sharp distinction. Most importantly, information stored in working memory has been shown to modulate selective attention processing – and vice versa. At the theoretical level, these observations are paralleled by an increasingly dominant focus on working memory as (involving) the attended part of long-term memory, with some positions considering that working memory is equivalent to selective attention turned to long-term memory representations – or internal selective attention. This questions the existence of working memory as a dedicated cognitive function and raises the need for integrative accounts of working memory and attention. The next step will be to explore the precise implications of attentional accounts of WM for the understanding of specific aspects and characteristics of WM, such as serial order processing, its modality-specificity, its capacity limitations, its relation with executive functions, as well as the nature of attentional mechanisms involved. This research topic in Frontiers in Human Neuroscience aims at bringing together the latest insights and findings about the interplay between working memory and selective attention

The role of subjective experiences in conflict tasks : a review

Cognitive control research is concerned with the question how we install adaptive behaviour in the case of (cognitive) conflict. In this review we focus on the role that awareness of this conflict plays in our ability to exert cognitive control. We will argue that visual conflict is not the only building block of metacognitive experiences of conflict and discuss how they are related to cognitive control. So, a first aim of the current review is to understand how these different metacognitive judgements are created. To do so, we draw some remarkable parallels with research on metacognition in decision making and memory research. Next, we elaborate on the relationship between metacognition and adaptive behaviour, with a specific focus on the role of subjective experiences in the Gratton effect. The grey areas that persist in the current literature are highlighted. In addition to deciphering the mechanisms of metacognitive judgements in cognitive control, this overview also aims to further enlarge our understanding of metacognitive abilities at a more general level

Metacognition and cognitive control : behavioural adaptation requires conflict experience

Cognitive control allows adapting our behaviour to improve performance. A behavioural signature of cognitive control is the Gratton effect. This effect is observed in conflict tasks and indicates smaller congruency effects after incongruent trials than after congruent trials. Metacognitive experience may play a role in this effect: When participants introspect on their conflict experience, the Gratton effect follows the conflict introspection instead of the stimulus congruency. However this Gratton effect could also be triggered by the labelling that the introspective method implies and/or by a misperception of the stimulus conflict. The current study investigated whether the experiential component of the introspection is necessary to trigger cognitive control or whether labelling a trial as conflicting or not can be sufficient. In a priming task, Gratton effects following metacognitive conflict experience and conflict label were contrasted. Replicating earlier reports, results showed that the metacognitive experience of conflict can trigger a Gratton effect. However a conflict label, either generated by the participants themselves or presented to the participants via feedback was not able to induce cognitive control. Results are discussed in light of current theories of cognitive control

Non-spatial neglect for the mental number line

Several psychophysical investigations, expanding the classical introspective observations by Galton, have suggested that the mental representation of numbers takes the form of a number line along which magnitude is positioned in ascending order according to reading habits, i.e. from left to right in Western cultures. In keeping with the evidence, pathological rightward deviations in the bisection of number intervals due to right brain damage are generally interpreted as originating from a purely spatial-attentional deficit in the processing of the left side of number intervals. However, consistent double dissociations between defective processing of the left side of physical and mental number space have called into question the universality of this interpretation. Recent evidence suggests a link between rightward deviations in number space and defective memory for both spatial and non-spatial sequences of items. Here we describe the case of a left brain-damaged patient exhibiting right-sided neglect for extrapersonal and representational space, and left-sided neglect on the mental number line. Accurate neuropsychological examination revealed that the apparent left-sided neglect in the bisection of number intervals had a purely non-spatial origin and was based on mnemonic difficulties for the initial items of verbal sequences presented visually at an identical spatial position. These findings show that effective position-based verbal working memory might be crucial for numerical tasks that are usually considered to involve purely spatial representation of numerical magnitudes. © 2011 Elsevier Ltd.SCOPUS: ar.jinfo:eu-repo/semantics/publishe