Lien entre l'activité pariéto-occipitale enregistrée pendant une tâche de mémoire à court terme visuelle et les habiletés mathématiques : une étude en magnétoencéphalographie

La mémoire à court terme visuelle (MCTv) est un système qui permet le maintien temporaire de l’information visuelle en mémoire. La capacité en mémoire à court terme se définit par le nombre d’items qu’un individu peut maintenir en mémoire sur une courte période de temps et est limitée à environ quatre items. Il a été démontré que la capacité en MCTv et les habiletés mathématiques sont étroitement liées. La MCTv est utile dans beaucoup de composantes liées aux mathématiques, comme la résolution de problèmes, la visualisation mentale et l’arithmétique. En outre, la MCTv et le raisonnement mathématique font appel à des régions similaires du cerveau, notamment dans le cortex pariétal. Le sillon intrapariétal (SIP) semble être particulièrement important, autant dans la réalisation de tâches liées à la MCTv qu’aux habiletés mathématiques. Nous avons créé une tâche de MCTv que 15 participants adultes en santé ont réalisée pendant que nous enregistrions leur activité cérébrale à l’aide de la magnétoencéphalographie (MEG). Nous nous sommes intéressés principalement à la composante SPCM. Une évaluation neuropsychologique a également été administrée aux participants. Nous souhaitions tester l’hypothèse selon laquelle l’activité cérébrale aux capteurs pariéto-occipitaux pendant la tâche de MCTv en MEG sera liée à la performance en mathématiques. Les résultats indiquent que l’amplitude de l’activité pariéto-occipitale pendant la tâche de MCTv permet de prédire les habiletés mathématiques ainsi que la performance dans une tâche de raisonnement perceptif. Ces résultats permettent de confirmer le lien existant entre les habiletés mathématiques et le fonctionnement sous-jacent à la MCTv.

Desenvolvimento de competências de cálculo em crianças com Síndrome de Down

A falta de pesquisas ao nível do desenvolvimento de competências matemáticas básicas em crianças com SD, a par da sua importância na aquisição de aprendizagens úteis para a vida quotidiana destes indivíduos, são os principais motivos pelos quais este trabalho de investigação-ação propôs observar e analisar qual o contributo de um material multissensorial – Numicon – no desenvolvimento de competências relacionadas com o cálculo nestas crianças. Para tal, foram promovidas algumas sessões de trabalho, com este material, com uma criança com SD em idade escolar, planificadas a partir da identificação das suas capacidades e dificuldades matemáticas iniciais através de entrevistas e de uma avaliação diagnóstica. No final da intervenção, foi feita uma reavaliação da aluna e uma reflexão sobre a análise comparativa dos resultados obtidos em ambas as avaliações. Verificou-se que, apesar de curta, esta intervenção conduziu a aluna a evidentes progressos no que respeita a alguns dos conceitos trabalhados, o que leva a crer que a utilização deste material manipulável, ao permitir a concretização de conceitos abstratos, facilita a aprendizagem de ideias matemáticas e a aquisição de competências essenciais para uma vida quotidiana independente e ativa. No final do trabalho são sugeridas algumas possibilidades de desdobramento deste estudo para futuras pesquisas.

Economic analysis of international supply chains: an internalization perspective

Offshoring and outsourcing in global value chains have been extensively analyzed from a strategic management perspective (Gereffi & Li, 2012; Gereffi, Humphrey & Sturgeon, 2005; Mudambi & Venzin, 2010). This paper examines these issues from an internalization theory perspective by summarizing the contribution of internalization theory to supply chain analysis; considering how a division of labor is coordinated and comparing coordination by management with coordination by the market; and discussing the formal models of supply chains developed by economists. Supply chain researchers possessing an interest in economic principles and good mathematical skills can make an important contribution to internalization theory, and it is hoped that this paper will encourage them to do so.

Globos e mapas ao alcance das mãos : ensino de matemática numa perspectiva de alfabetização funcional na EJA

The following dissertation has as its main advantage the privilege of visualizing the literacy processes through the angle of the functional perspective, which does not see the literary process as a practice solely based on the decoding of alphabetical codes, and then allows for the opening of ample spaces for the allocation of mathematical skills in the realms of the functional literacy. The main object of this study was to investigate which are the contributions that a sequence of activities and of methodologies developed for the teaching of Geometry could provide for a part of the functional literacy process in mathematics of youngsters and adults of EJA, corresponding to the acquisition or to the improvement of skills related to the orientation capacity. The focus of the analyses consisted in the practice of these activities with the young and adult students of an EJA class belonging to a municipal public school of Natal/RN. The legacies of Paulo Freire about the redimensioning of the role of the teacher, of the students, of the knowledge and of their connections within the teaching-learning process, prevailed in the actions of the methodology implemented in the classroom and, especially, in the establishing of dialogic connections with the students, which directed all the observations and analyses regarding the collected information. The results indicated that the composition of articulations between the teaching of mathematics and the exploration of maps and the earth globe enabled the creation of multidisciplinary learning environments and situations, where we could observe, gradually, the development of procedures and attitudes indicating the evolution of space-visual type skills

Number Processing and Calculation in Brazilian Children Aged 7-12 Years

Numerical cognition is based on two components - number processing and calculation. Its development is influenced by biological, cognitive, educational, and cultural factors. The objectives of the present study were to: i) assess number processing and calculation in Brazilian children aged 7-12 years from public schools using the Zareki-R (Battery of neuropsychological tests for number processing and calculation in children, Revised; von Aster & Dellatolas, 2006) in order to obtain normative data for Portuguese speakers; ii) identify how environment, age, and gender influences the development of these mathematical skills; iii) investigate the construct validity of the Zareki-R by the contrast with the Arithmetic subtest of WISC-III. The sample included 172 children, both genders, divided in two groups: urban (N= 119) and rural (N= 53) assessed by the Zareki-R. Rural children presented lower scores in one aspect of number processing; children aged 7-8 years demonstrated an inferior global score than older; boys presented a superior performance in both number processing and calculation. Construct validity of Zareki-R was demonstrated by high to moderate correlations with Arithmetic subtest of WISC-III. The Zareki-R therefore is a suitable instrument to assess the development of mathematical skills, which is influenced by factors such as environment, age, and gender.

Etnomatemática e economia solidária: o caso de um grupo de fabricação de sabão caseiro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

O efeito do treino musical sobre a capacidade da memória operacional e da cognição numérica de crianças com discalculia do desenvolvimento

Pós-graduação em Psicologia do Desenvolvimento e Aprendizagem - FC

Habilidades matemáticas e memória operacional em crianças de 7 a 12 anos infectadas pelo HIV por transmissão vertical, em estado assintomático

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

A resolução de problemas na licenciatura em Matemática: análise de um processo de formação no contexto do estágio curricular supervisionado

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Sequências de números reais: uma abordagem no ensino médio

Pós-graduação em Matemática em Rede Nacional - IBILCE

Development of numerical cognition among Brazilian school-aged children

The Numerical Cognition is influenced by biological, cognitive, educational, and cultural factors and entails the following systems: Number Sense (NS) represents the innate ability to recognize, compare, add, and subtract small quantities, without the need of counting; Number Production (NP) which includes reading, writing and counting numbers or objects; Number Comprehension (NC), i.e., the understanding the nature of the numerical symbols and their number, and the calculation (CA). The aims of the present study were to: i) assess theoretical constructs (NS, NC, NP and CA) in children from public schools from 1 st -to 6 th - grades; and ii) investigate their relationship with schooling and working memory. The sample included 162 children, both genders, of 7-to 12-years-old that studied in public school from 1 st -to 6 th -grades, which participated in the normative study of Zareki-R (Battery of neuropsychological tests for number processing and calculation in children, Revised; von Aster & Dellatolas, 2006). Children of 1 st and 2 nd grades demonstrated an inferior global score in NC, NP and CA. There were no genderrelated differences. The results indicated that the contribution of NS domain in Zareki-R performance is low in comparison to the other three domains, which are dependent on school-related arithmetic skills.

A construção da ideia de número na educação infantil

This paper seeks to understand-the process by which the child in kindergarten builds the idea of number. Therefore we developed a qualitative study of phenomenological approach that involved field work in the classroom with children of four and five years. Starting from their real-world contexts, their experiences and using the natural language tasks are designed to help the student to go beyond the already known, analyzing how they thinks and what knowledge they bring their lived experience. By interference carried expanded mathematical ideas acquired. The analysis and interpretation of research data shows that the idea of number is built by children from all kinds of relationships created between objects and the world around them, and the more diverse are these experiences, the greater the understanding opportunities and development of mathematical skills and competencies. It showed also that, in kindergarten, children tread just a few ways to build the idea of number

A construção da ideia de número na educação infantil

This paper seeks to understand-the process by which the child in kindergarten builds the idea of number. Therefore we developed a qualitative study of phenomenological approach that involved field work in the classroom with children of four and five years. Starting from their real-world contexts, their experiences and using the natural language tasks are designed to help the student to go beyond the already known, analyzing how they thinks and what knowledge they bring their lived experience. By interference carried expanded mathematical ideas acquired. The analysis and interpretation of research data shows that the idea of number is built by children from all kinds of relationships created between objects and the world around them, and the more diverse are these experiences, the greater the understanding opportunities and development of mathematical skills and competencies. It showed also that, in kindergarten, children tread just a few ways to build the idea of number

Cognitive Interventions with Children with Special Needs - Transfer effects and multidisciplinary perspectives

Our last study with regularly developed children demonstrated a positive effect of working memory training on cognitive abilities. Building upon these findings, the aim of this multidisciplinary study is to investigate the effects of training of core functions with children who are suffering from different learning disabilities, like AD/HD, developmental dyslexia or specific language impairment. In addition to working memory training (BrainTwister), we apply a perceptual training, which concentrates on auditory-visual matching (Audilex), as well as an implicit concept learning task. We expect differential improvements of mental capacities, specifically of executive functions (working memory, attention, auditory and visual processing), scholastic abilities (language and mathematical skills), as well as of problem solving. With that, we hope to find further directions regarding helpful and individually adapted interventions in educational settings. Interested parties are invited to discuss and comment the design, the research question, and the possibilities in recruiting the subjects.

Teaching and evaluating mechanical vibrations with Matlab®

The study of the response of mechanical systems to external excitations, even in the simplest cases, involves solving second-order ordinary differential equations or systems thereof. Finding the natural frequencies of a system and understanding the effect of variations of the excitation frequencies on the response of the system are essential when designing mechanisms [1] and structures [2]. However, faced with the mathematical complexity of the problem, students tend to focus on the mathematical resolution rather than on the interpretation of the results. To overcome this difficulty, once the general theoretical problem and its solution through the state space [3] have been presented, Matlab®[4] and Simulink®[5] are used to simulate specific situations. Without them, the discussion of the effect of slight variations in input variables on the outcome of the model becomes burdensome due to the excessive calculation time required. Conversely, with the help of those simulation tools, students can easily reach practical conclusions and their evaluation can be based on their interpretation of results and not on their mathematical skills