Visuospatial Working Memory

Cette thèse prend pour objet un aspect peu étudié de la mémoire, la mémoire de travail visuo-spatiale et se donne comme objectif d’étudier le maintien à court terme des informations visuo-spatiales, comme il a été mis en évidence dans le maintien du matériel verbal (boucle phonologique). La partie théorique est une revue de questions sur la mémoire immédiate et notamment les aspects visuels et spatiaux de la mémoire. La partie empirique est réalisée à partir de plusieurs expériences sur l’adulte normal et s’appuie sur le paradigme des tâches interférentes. La première recherche pose un cadre général en dissociant expérimentalement les trois modules du modèle de Mémoire de Travail de Baddeley et Hitch (1974). Un second groupe de recherches vise à montrer la fonctionnalité d’un mécanisme de rafraîchissement visuo-spatial en mettant en évidence un effet longueur de parcours et les facteurs qui le soutiennent à travers la mise au point d'une tâche de mémoire immédiate visuo-spatiale peu usitée. Un troisième groupe de recherches teste le caractère général de l’effet longueur de parcours. Une dernière recherche teste le fonctionnement du mécanisme de rafraîchissement dans le cadre général de la Mémoire de Travail.

Depuis l’Antiquité, de nombreuses activités font référence au domaine du Visuel, de l’Imagé, du Visuo-Spatial, … En dépit de nombreux travaux, cette « mémoire visuo-spatiale » reste mal définie et la terminologie est relativement confuse.
Lors de la première expérience présentée, notre principal objectif était de permettre une meilleure définition des caractéristiques qui composent cette mémoire visuo-spatiale. Ainsi, diverses épreuves représentatives de courants théoriques, ont été choisies. Epreuves issues : 1/- du double codage (« grilles » type memory-test ; « mémoire imagée »), 2/- de la mémoire de travail (« matrices » ; épreuve de mémoire visuelle de WMS-R), 3/- des théories de la perception visuelle (test de jugement de direction de lignes de Benton ; « mémoire visuelle »).
Lors de la seconde expérience, diverses tâches secondaires interférentes ont été introduites après 2 tâches principales, de localisation spatiale (localiser le parcours d’un point dans une matrice) ou de patterns visuels (mémorisation d’un nombre croissant de points dans une matrice). Les résultats montrent que seules les tâches secondaires « visuelles » (détecter les couleurs) et « spatio-motrice » (toucher en aveugle les coins d’un carré) créent une interférence uniquement pour la tâche principale des patterns visuels (par rapport à la tâche contrôle). Les tâches secondaires « visuospatiales » semblant impliquer une intégration du visuel et du spatial (tâche de « localisation de lieux » : inspirée de la méthode des lieux ; tâche de direction sur une horloge virtuelle) créent une forte interférence (-30 à –40%) à la fois de la tâche principale de localisations et de la tâche de patterns. Ces résultats semblent exclure que le « spatial » ait une composante motrice mais conduisent à l’hypothèse d’une mémoire visuospatiale intégrée, différente d’une mémoire visuelle ou imagée.
SUMMARY : WHAT MEMORY, MEASURE « VISUO-SPATIAL » TASKS ?

Since Antiquity, many activities refer to field of visual, imaged, visuo-spatial, … In spite of many works, this “visuo-spatial memory” remains badly defined and terminology is relatively vague.
The principal objective of our first experiment was to ensure a better definition of the characteristics making up this visuo-spatial memory. Several representative tasks of theoretical fields were selected. Tasks coming from: 1/- double coding (“grids”, memory-type test; imaged memory), 2/- working memory (“matrix”; test of visual memory WMS-R), 3/- theory of visual perception (test of judgment of direction of lines of Benton; visual memory).
These tests comprise variants (order, colour,  ..) and lead to 12 scores. 4 principal factors emerge from the analysis of principal component (APC): 1/- a factor involved in the storage of pictures and their verbal encoding; 2/- a factor of visual information storage; 3/- a factor corresponding to the treatment of information link on to spatial locations; 4/- a factor relating to working memory, corresponding to visuo-spatial sketchpad with central executive.
In the second experiment, several secondary tasks of interference were introduced after two principal tasks based either on spatial location (to localize the route of a point in a matrix) or on visual configuration (memorization of growing number of points in a matrix). The results indicated that only the secondary tasks “visual” (to detect colours) and “spatio-motor” (to touch blindly the corner of square) induce an interference exclusively for the principal visual configuration task (compared with control task). The “visuospatial” secondary tasks pretending to involve an integration of visual and spatial (task of locations of places: based on the “method of loci”; task of direction on a virtual clock) induced a major interference (-30 to –40%) for principal location task and the main visual task. The results seem to suggest that the principal memory did not have a motor component, and they lead us to a hypothesis of an integrated visuospatial memory, as opposed to a visual memory.
KEY-WORDS
Memory, Visuospatial, Visual, Motor.

En dépit de nombreux travaux récents, la mémoire impliquant les tâches visuo-spatiales reste mal définie.
Dans les deux expériences présentées, ont été introduites diverses tâches secondaires interférentes après deux tâches principales, de localisation spatiale ou de patterns visuels.
Dans l’expérience 1, seule la tâche secondaire « visuelle » crée une interférence et uniquement pour la tâche principale des patterns visuels.
Dans l’expérience 2, sont introduites deux tâches dites « visuospatiales » impliquant une intégration du visuel et du spatial. Ces tâches créent une forte interférence (-30 à –40%) aux deux tâches principales. Ces résultats semblent exclure que le « spatial » ait une composante motrice mais conduisent à l’hypothèse d’une mémoire visuospatiale intégrée, différente d’une mémoire visuelle ou imagée.
Dans la troisième expérience, la tâche principale consiste à mémoriser une séquence d’emplacements dans un bicube. La tâche tridimensionnelle provoque une baisse de 14% par rapport à l’approche en perspective (2D1/2). Les représentations en relief sont proche du 2D1/2 , c’est-à-dire de l’espace fabriqué par les indices perceptifs.

There is some debate surrounding the cognitive resources underlying backwards digit recall. Some researchers consider it to differ from forwards digit recall due to the involvement of executive  control, while others suggest that backwards recall involves visuo-spatial resources. Four experiments therefore investigated the role of executive-attentional and visuo-spatial resources in both forwards and backwards digit recall. In the first, participants completed visuo-spatial 0-back and 2-back tasks during the encoding of information to be remembered. The concurrent tasks did not differentially disrupt performance on backwards digit recall relative to forwards digit recall. Experiment 2 shifted concurrent load to the recall phase instead, and in this case revealed a larger effect of both tasks on backwards recall relative to forwards recall, suggesting that backwards recall may draw on additional resources during the recall phase and that these resources are visuo-spatial in nature. Experiments 3 and 4 then further investigated the role of visual processes in forwards and backwards recall using dynamic visual noise (DVN). In Experiment 3 DVN was presented during encoding of information to be remembered, and had no effect upon performance. However, in Experiment 4 it was presented during the recall phase, and the results provided evidence of a role for visual imagery in backwards digit recall. These results were replicated in Experiment 5 in which the same list length was used for forwards and backwards recall tasks. The findings are discussed in terms of both theoretical and practical implications.

Cette these prend pour objet un aspect peu etudie de la memoire, la memoire de travail visuo-spatiale et se donne comme objectif d'etudier le maintien a court terme des informations visuo-spatiales, comme il a ete mis en evidence dans le maintien du materiel verbal (boucle phonologique). La partie theorique est une revue de questions sur la memoire immediate et notamment les aspects visuels et spatiaux de la memoire. La partie empirique est realisee a partir de plusieurs experiences sur l'adulte normal et s'appuie sur le paradigme des tâches interferentes. La premiere recherche pose un cadre general en dissociant experimentalement les trois modules du modele de Memoire de Travail de Baddeley et Hitch (1974). Un second groupe de recherches vise a montrer la fonctionnalite d'un mecanisme de rafraichissement visuo-spatial en mettant en evidence un effet longueur de parcours et les facteurs qui le soutiennent a travers la mise au point d'une tâche de memoire immediat...

Learning a visuomotor skill involves a distributed network which includes the primary motor cortex (M1). Despite multiple lines of evidence supporting the role of M1 in motor learning and memory, it is unclear whether M1 plays distinct roles in different aspects of learning such as acquisition and retention. Here, we investigated the nature and chronometry of that processing through a temporally specific disruption of M1 activity using single-pulse transcranial magnetic stimulation (TMS). We applied single-pulse TMS to M1 or dorsal premotor cortex (PMd) during adaptation of rapid arm movements (ϳ150 ms duration) to a visuomotor rotation. When M1 was stimulated either immediately after the end of each trial or with a 700 ms delay, subjects exhibited normal adaptation. However, whereas the memory of the subjects who received delayed-TMS showed normal rates of forgetting during deadaptation, the memory of those who received immediate TMS was more fragile: in the deadaptation period, they showed a faster rate of forgetting. Stimulation of PMd with adjusted (reduced) intensity to rule out the possibility of coactivation of this structure caused by the current spread from M1 stimulation did not affect adaptation or retention. The data suggest that, during the short time window after detection of movement errors, neural processing in M1 plays a crucial role in formation of motor memories. This processing in M1 may represent a slow component of motor memory which plays a significant role in retention.

Theoretical models of working memory suggest that the simultaneous processing and storage of information is carried out either as separate or binded mechanisms. We explored working memory capacity and strategy in two elite groups of experts to test the separate versus binded hypotheses. Visuospatial and verbal abilities were measured in elite nationally ranked SCRABBLE and crossword experts and compared with college students matched on quantitative and verbal SAT scores, both exceeding 700 on average. SCRABBLE and crossword experts significantly outperformed college students on all cognitive measures. The crossword experts scored significantly higher on a test of analogies than SCRABBLE experts, but performance for cognitive ability tasks did not significantly differ between expert groups. The techniques and strategies used during competitive play, however, did differ significantly. Findings suggest that visuospatial and verbal working memory capacities of SCRABBLE and crossword experts are binded and occur at extraordinarily high levels.

The notion of "mental maps" will therefore be considered according to two different meanings and uses: 1) the internal representation of a space travelled through (cognitive map) and 2) the representation of a set of entities or concepts (mind map). The terms "memory transcription" can be understood as the translation and recording on a graphic support of elements present in the mind. The terms of "symbolic projection" are conceived as the fact of externalizing by the means of signs or symbols on a graphic support, the two types of representation: the representation of a traversed space or the representation of a set of entities or concepts. The points of contact, crossover, reversal, between what could be called "representation of space" and "space of representation" are little explored. How can we better apprehend the complex notion of "mental map"? The question of memory transcription? Of the "symbolic projection"? Can we identify meeting points between these two polarities and if possible a continuum?

Visuospatial bootstrapping is the name given to a phenomenon whereby performance on visually presented verbal serial-recall tasks is better when stimuli are presented in a spatial array rather than a single location. However, the display used has to be a familiar one. This phenomenon implies communication between cognitive systems involved in storing short-term memory for verbal and visual information, alongside connections to and from knowledge held in long-term memory. Bootstrapping is a robust, replicable phenomenon that should be incorporated in theories of working memory and its interaction with long-term memory. This article provides an overview of bootstrapping, contextualizes it within research on links between long-term knowledge and short-term memory, and addresses how it can help inform current working memory theory.

Dispositional anxiety is a well-established risk factor for the development of psychiatric disorders along the internalizing spectrum, including anxiety and depression. Importantly, many of the maladaptive behaviors characteristic of anxiety, such as anticipatory apprehension, occur when threat is absent. This raises the possibility that anxious individuals are less efficient at gating threat’s access to working memory, a limited capacity workspace where information is actively retained, manipulated, and used to flexibly guide goal-directed behavior when it is no longer present in the external environment. Using a well-validated neurophysiological index of working memory storage, we demonstrate that threat-related distracters were difficult to filter on average and that this difficulty was exaggerated among anxious individuals. These results indicate that dispositionally anxious individuals allocate excessive working memory storage to threat, even when it is irrelevant to the task at hand. More broadly, these results provide a novel framework for understanding the maladaptive thoughts and actions characteristic of internalizing disorders.

It is proposed that emotional and cognitive functions may be differentiated based on sex. However, it is still unknown whether this assumption could be generalized for all emotional faces and working memory (WM) functions. To examine this, 50 females, and 60 males performed an emotion recognition task, consisting of a series of emotional faces as well as three working memory tasks from Cambridge Neuropsychological test battery (CANTAB); namely, spatial working memory (SWM), stocking of Cambridge (SOC), and intra/extradimensional shifts tasks (IED). The results found that females had faster response times in recognition of both positive and negative faces as compared to males. Furthermore, it was observed that while females were better on SWM task processing, males performed better on IED and four move SOC tasks, illustrating that processing of WM components may differentiate by sex. It has been concluded that emotional and cognitive functions are indeed sensitive to sex differences.

ABSTRACT Theoretical models of working memory suggest that the simultaneous processing and storage of information is carried out either as separate or binded mechanisms. We explored working memory capacity and strategy in two elite groups of experts to test the separate versus binded hypotheses. Visuospatial and verbal abilities were measured in elite nationally ranked SCRABBLE and crossword experts and compared with college students matched on quantitative and verbal SAT scores, both exceeding 700 on average. SCRABBLE and crossword experts significantly outperformed college students on all cognitive measures. The crossword experts scored significantly higher on a test of analogies than SCRABBLE experts, but performance for cognitive ability tasks did not significantly differ between expert groups. The techniques and strategies used during competitive play, however, did differ significantly. Findings suggest that visuospatial and verbal working memory capacities of SCRABBLE and crossword experts are binded and occur at extraordinarily high levels. Copyright © 2014 John Wiley & Sons, Ltd.