Effect of a virtual environment on the development of mathematical skills in children with dyscalculia.

In this study, we show the effectiveness of a virtual environment comprising 18 computer games that cover mathematics topics in a playful setting and that can be executed on the Internet with the possibility of player interaction through chat. An arithmetic pre-test contained in the Scholastic Performance Test was administered to 300 children between 7 and 10 years old, including 162 males and 138 females, in the second grade of primary school. Twenty-six children whose scores showed a low level of mathematical knowledge were chosen and randomly divided into the control (CG) and experimental (EG) groups. The EG participated to the virtual environment and the CG participated in reinforcement using traditional teaching methods. Both groups took a post-test in which the Scholastic Performance Test (SPT) was given again. A statistical analysis of the results using the Student's t-test showed a significant learning improvement for the EG and no improvement for the CG (p≤0.05). The virtual environment allows the students to integrate thought, feeling and action, thus motivating the children to learn and contributing to their intellectual development.

Developmental dyscalculia in children and adolescents with idiopathic epilepsies in a Brazilian sample.

Epilepsy is one of the most prevalent chronic disorders of childhood which can threaten child development and mental health. Among cognitive disorders, dyscalculia is one of the most important. In this study, 39 children and adolescents with idiopathic epilepsy underwent clinical and neuropsychological assessment to determine the intellectual level, math skills, reading and writing performance and neuropsychological profile. It was observed that the mathematical ability was below schooling expectations in a higher frequency than expected. There were no significant differences in mathematical performance among groups divided by number of antiepileptic drugs used, duration of disease and types and frequency of seizures. There was a positive correlation with intelligence quotient and attentional and reading level. These results suggest the existence not only of dyscalculia, but the concurrence of attentional and reading problems for the poor mathematical performance in this population.

Developmental dyscalculia in children and adolescents with idiopathic epilepsies in a Brazilian sample / Avaliação de discalculia do desenvolvimento em crianças e adolescentes com epilepsia idiopática em uma amostra brasileira

Epilepsy is one of the most prevalent chronic disorders of childhood which can threaten child development and mental health. Among cognitive disorders, dyscalculia is one of the most important. In this study, 39 children and adolescents with idiopathic epilepsy underwent clinical and neuropsychological assessment to determine the intellectual level, math skills, reading and writing performance and neuropsychological profile. It was observed that the mathematical ability was below schooling expectations in a higher frequency than expected. There were no significant differences in mathematical performance among groups divided by number of antiepileptic drugs used, duration of disease and types and frequency of seizures. There was a positive correlation with intelligence quotient and attentional and reading level. These results suggest the existence not only of dyscalculia, but the concurrence of attentional and reading problems for the poor mathematical performance in this population.

A epilepsia é uma das doenças crônicas mais comuns da infância que pode ameaçar o desenvolvimento infantil e saúde mental. Dos distúrbios cognitivos, a discalculia é um dos mais importantes. Neste estudo, 39 crianças e adolescentes com epilepsia idiopática, foram submetidos à avaliação clínica e neuropsicológica para determinar o nível intelectual, habilidade em matemática, leitura e escrita e perfil neuropsicológico. Observou-se que a habilidade em matemática ficou abaixo das expectativas de escolarização em uma frequência maior do que a esperada. Não houve diferenças significativas no desempenho matemático em relação ao número de drogas antiepilépticas utilizadas, duração da doença, tipo e frequência das crises. Houve uma correlação positiva com o quociente de inteligência e nível de atenção e leitura. Estes resultados sugerem a existência não só de discalculia, mas também a existência de problemas atencionais e de leitura que fatores causais para a dificuldade matemática apresentada nesta amostra.

Symbolic and non-symbolic number magnitude processing in children with developmental dyscalculia.

The aim of this study was to evaluate if children with Developmental Dyscalculia (DD) exhibit a general deficit in magnitude representations or a specific deficit in the connection of symbolic representations with the corresponding analogous magnitudes. DD was diagnosed using a timed arithmetic task. The experimental magnitude comparison tasks were presented in non-symbolic and symbolic formats. DD and typically developing (TD) children showed similar numerical distance and size congruity effects. However, DD children performed significantly slower in the symbolic task. These results are consistent with the access deficit hypothesis, according to which DD children's deficits are caused by difficulties accessing magnitude information from numerical symbols rather than in processing numerosities per se.

La implicación de la memoria de trabajo en la resolución mental de problemas aritméticos / The involvement of working memory in mental arithmetic problem solving: the case of dyscalculia

Para resolver problemas aritméticos, los humanos necesitamos tratar con diferentes piezas de información. Por esta razón, parece plausible que necesitemos de algún sistema capaz de procesar, retener y manipular dicha información. La memoria de trabajo es el sistema encargado de llevar a cabo estos procesos, por lo que podría estar implicado en la resolución de operaciones aritméticas. En este sentido, la investigación empírica ha mostrado que los diferentes componentes de la memoria de trabajo (el ejecutivo central, el bucle fonológico, y la agenda visoespacial) juegan diferentes roles en el proceso de resolución de problemas aritméticos. Por otro lado, algunos investigadores sugieren que la discalculia evolutiva, la dificultad para llevar a cabo operaciones matemáticas más frecuente en la población, se caracteriza por un déficit principal en la memoria de trabajo. Sin embargo, estos resultados no han sido siempre replicados. En este artículo se presenta una revisión actualizada de la implicación de la memoria de trabajo en la resolución de operaciones aritméticas. Como se verá, cada componente cumple con una función específica en el proceso de resolución de operaciones aritméticas. Además, la evidencia en contra y apoyando un déficit principal en memoria de trabajo en pacientes con discalculia del desarrollo será revisada.

To solve arithmetic problems, humans need to deal with several pieces of information. The working memory system actively stores and manipulates information. For this reason, it seems plausible that this system is involved in solving arithmetic problems. In fact, it has been shown that the different subcomponents of working memory (central executive, phonological loop and visual sketchpad) play different roles in solving arithmetic problems. On the other hand, some research has shown that the most typical arithmetic disability, that is developmental dyscalculia, is characterized by a main deficit in working memory. However, these results have not been always obtained. In the present article the involvement of working memory in solving arithmetic operations is reviewed. Moreover, the evidence supporting and against a main impairment in working memory in people with developmental dyscalculia will be discussed.

Basic numerical capacities and prevalence of developmental dyscalculia: the Havana Survey.

The association of enumeration and number comparison capacities with arithmetical competence was examined in a large sample of children from 2nd to 9th grades. It was found that efficiency on numerical capacities predicted separately more than 25% of the variance in the individual differences on a timed arithmetical test, and this occurred for both younger and older learners. These capacities were also significant predictors of individual variations in an untimed curriculum-based math achievement test and on the teacher scores of math performance over developmental time. Based on these findings, these numerical capacities were used for estimating the prevalence and gender ratio of basic numerical deficits and developmental dyscalculia (DD) over the grade range defined above (N = 11,652 children). The extent to which DD affects the population with poor ability on calculation was also examined. For this purpose, the prevalence and gender ratio of arithmetical dysfluency (AD) were estimated in the same cohort. The estimated prevalence of DD was 3.4%, and the male:female ratio was 4:1. However, the prevalence of AD was almost 3 times as high (9.35%), and no gender differences were found (male:female ratio = 1.07:1). Basic numerical deficits affect 4.54% of school-age population and affect more boys than girls (2.4:1). The differences between the corresponding estimates were highly significant (α < .01). Based on these contrastive findings, it is concluded that DD, defined as a defective sense of numerosity, could be a distinctive disorder that affects only a portion of children with AD.