2023

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2019

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2017

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Vendredi 27 janvier 2017 à 10h

Bert De SMEDT Katholiek Universiteit Leuven

What predicts arithmetic fluency? The role of symbolic numerical processing (and domain–general factors)

Being fluent and efficient in performing basic calculations has been regarded as an important building block for the development of mathematical skills. On the other hand, deficits in retrieving arithmetic facts from memory are the hallmark of children with dyscalculia. The ability to represent symbolic numerical magnitudes has been put forward as a major determinant of children’s general mathematics achievement. Does this factor then also contribute to the specific mathematical skills of arithmetic fluency, its development and its impairments? In this talk, I will present a series of recent cross-sectional and longitudinal studies in typically developing children, studies in children with dyscalculia and studies in children with genetic disorders all of which have investigated the role of numerical magnitude processing in the development of arithmetic fluency or the transition towards arithmetic fact retrieval. These studies also investigated the potential contributions of domain–general factors, such as working memory or inhibitory control. The key message from these studies is that particularly children’s symbolic magnitude processing skills are a unique and very stable predictor of children’s arithmetic (fact retrieval) development. These data all suggest that screening children’s symbolic processing skills is useful for detecting children at risk children and I will present data from a recent large-scale validation of such a screening measure.

à 11h

Evelyn H.Kroesbergen Universiteit Utrecht

Explaining individual differences in mathematics: Number sense, working memory, and creativity

Number sense, or the ability to understand and process numerical information, is thought to be a basic ability for later mathematical development. Recently, number sense has received growing attention in scientific literature. These recent findings have also raised important questions about what number sense actually is, how it can be measured, how it develops, and how it is related to mathematics. The focus of this presentation will lie on these questions, and recent empirical studies will be discussed.

Furthermore, many studies have shown the important influence of domain-general cognitive abilities (intelligence, language, working memory, executive functions) on mathematical development. We will discuss the role of working memory in mathematical development, by looking at several longitudinal, cross-sectional, and intervention studies. Special attention will be given to a recent study that showed that working memory not only plays a significant role in mathematics itself, but also in number sense. These results were confirmed in a recent meta-analysis on working memory and mathematics in elementary school children.
Thirdly, the role of creative thinking skills in math development is further discussed. Should creativity be seen as a domain-general trait, or is it more a domain-specific skill that should be trained to improve children’s math skills. Creativity can predict individual differences in math, even when controlling for working memory or IQ. The question then is why this aspect is almost neglected in current teaching practices in our (Dutch) schools and how this could be changed.

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2016

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Mardi 29 novembre 2016 à 10h30

Samuel SALVAGGIO UCL-IPSY

Journal Club

Balancing the 2 Hemispheres in Simple Calculation: Evidence From Direct Cortical Electrostimulation

Semenza et al., 2016, Cereb Cortex

How do the parietal lobes contribute to simple calculation? Clinical and neuroimaging methods, which are based mainly on correlational evidence, have provided contrasting results so far. Here we used direct cortical electrostimulation during brain surgery to causally infer the role of the left and right parietal lobes in simple calculation. Stimulation provoked errors for addition and multiplication in different parietal areas on both hemispheres. Crucially, an innovative qualitative error analysis unveiled the functional contrast of the 2 parietal lobes. Right or left stimulation led to different types of substitution errors in multiplication, unveiling the function of the more active hemisphere.
While inhibition of the left hemisphere led mainly to approximation errors, right hemisphere inhibition enhanced retrieval within a stored repertory. These results highlight the respective roles of each hemisphere in the network: rote retrieval of possible solutions by the left parietal areas and approximation to the correct solution by the right hemisphere. The bilateral orchestration between these functions guarantees precise calculation.

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Mardi 18 octobre 2016 à 10h30

Samuel SALVAGGIO UCL-IPSY

Embodiment of space perception: How hindering movement influences space perception?

Spatial representation is derived from a multi-sensory network involving vision, audition and vestibular information. The theory of embodied space cognition proposes that one’s objectives and capacities of acting within an environment will influence the perception and representation of this space. However, it still remains unclear whether perception or affordance biases may result from a moderation of action effort (or energy cost). The present research aims to address this issue by using virtual reality to keep the manipulations implicit. The movements performed by participants in virtual reality will either be increased or decreased in speed thus creating a mismatch between their real and virtual movement. Simultaneously, participants will either wear a heavy or a light wristband. We expect significant overestimation in distance estimation when movement cost is increased by either weight, decreased movement speed or both, while perceived reachability (i.e., the perceived limit of one’s reaching peripersonal space) should remain unchanged, as suggested by recent studies. The findings of this experiment should help building an understanding around the cognitive processes underlying spatial perception and representation.

Laurie GEERS UCL-IPSY

Differentiating physical and representational neglect to assess the role of spatial attention in mental arithmetic 

Several behavioural and neuroimaging studies have led to the conceptualization of number representation as spatially oriented along a crescent mental number line with small numbers represented on the left side and large numbers on the right side. Accordingly, the solving of subtraction and addition problems would require shifting attention respectively leftward and rightward along the number line. The present work tested the functional involvement of spatial attention in number processing and arithmetic by investigating the performances of a series of patients with left or right physical and/or representational neglect. The latter was specifically investigated since mental arithmetic by definition should be impaired only when attentional deficits extend to a representational level. The results did not allow us to test whether the spatial attention mechanisms specifically involved in numerical difficulties are representational in nature. However, results showed a double dissociation between small numbers/subtraction problems and large numbers/addition problems in left vs. right neglect patients, indicating that attention orientation to one side of space was required to process numbers and solve arithmetic problems. An additional dissociation between the two tasks of number processing suggested that attention orientation may however be involved according to the task used. Our results support the hypothesis of arithmetic as navigation processes along a mental number line and further illustrate how high-level cognition may rely on older evolutionary (i.e. visuospatial) functions to develop.

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Mercredi 8 juin 2016 à 10h

Attila KRAJCSI Department of Cognitive Psychology Eötvös Loránd University, Budapest (H)

An alternative model for symbolic number processing: the Discrete Semantic System

Analogue Number System (ANS), a representation working according to Weber’s law, is supposed to support many symbolic and non-symbolic number processing. We propose an alternative account for symbolic number processing, The Discrete Semantic System (DSS), which works similar to a semantic network or mental lexicon. In the talk I review some of the former empirical results that challenged the dominant ANS model, and that are in line with the DSS model. Additionally, several new empirical tests are presented that contrast the ANS and the DSS models. These new tests found that (a) symbolic numerical size effect is caused by the frequency of the digits, (b) symbolic numerical distance effect is caused by the association between the values and the small/large categories, (c) symbolic distance and size effects do not correlate, while nonsymbolic distance and size effects do, (d) symbolic number comparison task cannot be described by the psychophysics models, and (e) numbers interfere with the discrete parity property. All of these new results favor the DSS model.

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2015

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Mardi 29 septembre 2015 à 13h30

Konstantinos PRIFTIS (Dpt of General Psychology, University of Padova, I)

Newborn chicks and the number space

Abstract - It has been proposed that humans represent numbers along a mental number line (MNL), on which smaller numbers are located on the left and larger numbers are located on the right. Nonetheless, the origin of the MNL and its connections with cultural experience remain unclear. On the one hand, reading habits can influence the orientation of the MNL (left-to-right vs. right-to-left). On the other hand, pre-verbal infants and nonhuman species show a variety of numerical abilities, supporting the existence of evolutionary precursor-systems for number processing. We tackled the issue of the origin of the MNL, by studying number processing in newborn chicks. Results showed that three-day-old domestic chicks, once familiarized with a target number, spontaneously associated a smaller than the target number with the left side of space. By contrast, chicks associated a larger than the target number with the right side of space. We propose that the MNL might have a remote origin during species evolution. In humans, however, cultural factors can flexibly rearrange some aspects of the MNL (e.g., left-to-right vs. right-to-left orientation).

 

Wim GEVERS (ULB)

Approximately no sense in the number sense

Abstract - It is widely accepted that human and nonhuman species possess a specialized system to process large approximate numerosities. The theory of an evolutionarily ancient approximate number system (ANS) has received converging support from developmental studies, comparative experiments, neuroimaging, and computational modelling, and it is one of the most dominant and influential theories in numerical cognition. The existence of an ANS system is significant, as it is believed to be the building block of numerical development in general. The acuity of the ANS is related to future arithmetic achievements, and intervention strategies therefore aim to improve the ANS. Here we critically review current evidence supporting the existence of an ANS. Important shortcomings and confounds in existing empirical studies on human and non-human animals will be discussed, as well as in the logic used to build computational models that support the ANS theory. Rather than taking the ANS theory for granted, a more comprehensive explanation might be provided by a sensory-based system that compares or estimates large approximate numerosities by weighing the different sensory cues comprising number stimuli.

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Mardi 12 mai 2015 à 10h30

Elisabeth MARCHAND (IPSY, UCL)

Impact of spatial vs. non-spatial training on numerical development

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Mardi 17 février 2015 à 10h

Nastasya HONORE (IPSY, UCL)

Effets d'un entrainement de la mémoire de travail sur le développement numérique

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Mardi 6 janvier 2015 à 10h30

Anne LAFAY (Institut Universitaire de Santé Mentale, Québec, CA)

Troubles cognitifs numériques impliqués dans la dyscalculie développementale

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2014

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Mardi 15 avril 2014 à 10h30

Brian BUTTERWORTH (Institute of Cognitive Neuroscience, UCLondon, UK)

The development of arithmetical strategies and finger use

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Mercredi 02 avril 2014 à 10h 

Nathanaël Larigaldie (IPSY, UCL)

Interactions between numerosity and space: The Müller-Lyer Illusion

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Lundi 27 janvier 2014

Manuela PIAZZA (Center for Mind/Brain Sciences, University of Trento, IT)

Small set quantification and the multiple object tracking system

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2013

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Mardi 17 septembre 2013

Charline De Zutter (IPSY, UCL)

Précocité mathématique: Influence de différents facteurs cognitifs et numériques (Etude de cas)

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Mardi 9 juillet 2013

Nastasya HONORE (IPSY, UCL)

Quel système joue le rôle le plus important sur le développement numérique: le système d'approximation des nombres ou la représentation exacte des nombres ?

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Lundi 1 juillet 2013

Dénes SZUCS (Center for Neuroscience in Education, Cambridge University, UK)

Normal numerical development and developmental dyscalculia

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Mardi 30 avril 2013

Mariagrazia RANZINI  (Center for Research in Cognition & Neurosciences, ULB)

Number processing: From attention to action

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Mercredi 24 avril 2013

Irene MAMMARELLA (Dipartimento di Psicologia Generale, Università degli Studi di Padova, IT)

Some evidence about the relationship of working memory and school achievement

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Mardi 05 Février 2013

Valérie DORMAL (IPSY, UCL)

Mental arithmetic, Working memory and Visuo-Spatial attention: Attempts to disentangle the links

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Mardi 08 Janvier 2013

Virginie CROLLEN (IPSY, UCL)

Rôle des doigts dans le développement des procédures de comptage

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2012

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Mardi 18 Décembre 2012

Nastasya HONORE (IPSY, UCL)

Impact d'un entraînement de compétences numériques spécifiques sur le développement numérique

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Mardi 11 Décembre 2012

Alice DE VISSCHER (IPSY, UCL)

The role of interference in arithmetic facts storage

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ANNULE !

Sharlene NEWMAN (Cognitive Neuroimaging Lab, Indiana University)  http://psych.indiana.edu/faculty/sdnewman.php

The relationship between finger sense, arithmetic and general cognitive ability

This talk explores a contributor to the individual differences observed in number processing and arithmetic problem-solving, finger sense. While there is a growing literature that demonstrates the importance of finger sense in number and arithmetic processing, the precise role of finger sense in these processes has not been clearly characterized.  We take a developmental approach, examining children between 5 and 12 years of age. This is an age range in which finger sense shows a developmental difference (Reeves & Humberstone, 2011) and one in which arithmetic is being learned at the young end and mastered at the older end. The hypothesis tested is that the sensory and motor behavior of fingers plays an important role in number across the age range but that its role in arithmetic performance varies with development and is mediated by general cognitive abilities in older children. This hypothesis is supported by preliminary data which show that general cognitive measures were significantly different between groups of high and low finger sense children, but arithmetic performance was not different. However, arithmetic performance was affected by non-verbal intelligence measures, particularly in older children

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Vendredi 30 Novembre 2012

Mario BONATO (Computational Cognitive Neuroscience Lab, University of Padova) http://ccnl.psy.unipd.it/people/mario_bonato/mario-bonato-personal-page

When time is space: evidence for a mental time line

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Mardi 28 Février 2012

Valérie DORMAL (IPSY, UCL)

Parietal activation during numerosity and length processing : Similar or different neuronal populations?

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2011

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Mardi 20 Décembre 2011

Samuel DI LUCA & Gilles VANNUSCORPS (IPSY, UCL)

Number semantic rooted in sensory-motor schemas: a single case study

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Mardi 08 Novembre 2011

Stephane GRADE & Mauro PESENTI (IPSY, UCL)

Influence of left/right versus up/down gaze observation on number production

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Mardi 05 Juillet 2011

Laurence ROUSSELLE (IPSY, UCL)

Etude du rôle des doigts dans le développement d'une représentation symbolique exacte

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Lundi 30 Mai 2011

Ilaria BERTELETTI (CCNL, Padova)

Development of Ordinal Representations

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Mardi 24 Mai 2011

Anne-Francoise DE CHAMBRIER (doctorante de l'Université de Genève)

Résolutions de faits additifs chez des enfants tout-venant de 2ème primaire: comparaison entre une présentation auditivo-verbale et visuo-arabe, ainsi que leurs relations avec les représentations phonologiques et sémantiques des nombres en mémoire à long terme, avec la mémoire de travail et avec la mémoire auditive à court terme

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Mardi 11 Janvier 2011

Carmen DAVID (Babes - Bolyai University, Cluj-Napoca, Romania)

Is there a specific working memory deficit in dyscalculia?

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2010

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Vendredi 10 Décembre 2010

Alice DE VISSCHER (IPSY, UCL)

A specific impairment of multiplication in a case of developmental dyscalculia: rote verbal memories or up dating deficit?

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Mercredi 08 Décembre 2010

Samuel DI LUCA (IPSY, UCL)

Influence directe et indirecte de la taille numérique sur différentes tâches de barrages

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Mardi 26 Octobre 2010
 

Nicolas MASSON, Michael ANDRES & Valérie DORMAL (IPSY, UCL)

1ère partie : Exploration des processus d'estimation de numérosité et de durée chez les patients héminégligents

2ème partie : Arithmétique et Héminégligence : Les opérations arithmétiques impliquent-elles un déplacement de l'attention le long d'une ligne numérique mentale ?

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Mardi 23 Septembre 2010

Virginie Crollen (IPSY, UCL)

Traitement des nombres et de l'espace par les personnes aveugles

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Mardi 06 Juillet 2010

Thi Thu Hien Nguyen (IPSY, UCL)

Langage et nombres decimaux

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