Contributions from specific and general factors to unique deficits: two cases of mathematics learning difficulties

Mathematics learning difficulties are a highly comorbid and heterogeneous set of disorders linked to several dissociable mechanisms and endophenotypes. Two of these endophenotypes consist of primary deficits in number sense and verbal numerical representations. However, currently acknowledged endophenotypes are underspecified regarding the role of automatic vs. controlled information processing, and their description should be complemented. Two children with specific deficits in number sense and verbal numerical representations and normal or above-normal intelligence and preserved visuospatial cognition illustrate this point. Child H.V. exhibited deficits in number sense and fact retrieval. Child G.A. presented severe deficits in orally presented problems and transcoding tasks. A partial confirmation of the two endophenotypes that relate to the number sense and verbal processing was obtained, but a much more clear differentiation between the deficits presented by H.V. and G.A. can be reached by looking at differential impairments in modes of processing. H.V. is notably competent in the use of controlled processing but has problems with more automatic processes, such as nonsymbolic magnitude processing, speeded counting and fact retrieval. In contrast, G.A. can retrieve facts and process nonsymbolic magnitudes but exhibits severe impairment in recruiting executive functions and the concentration that is necessary to accomplish transcoding tasks and word problem solving. These results indicate that typical endophenotypes might be insufficient to describe accurately the deficits that are observed in children with mathematics learning abilities. However, by incorporating domain-specificity and modes of processing into the assessment of the endophenotypes, individual deficit profiles can be much more accurately described. This process calls for further specification of the endophenotypes in mathematics learning difficulties

DIAGNÓSTICO IN VIVO DA SENSIBILIDADE DE NEMATOIDES A DIFERENTES ANTIHELMÍNTICOS EM OVINOS CRIADOS EM SISTEMA SEMI-INTENSIVO

Grande variação no grau de resistência de populações de nematódeos é observada em grupos químicos, entre eles os anti-helmínticos, sendo este o principal entrave para obtenção do controle da verminose na ovinocultura. O objetivo do estudo foi avaliar a sensibilidade de nematoides de ovinos mestiços em criação semi-intensiva em três propriedades a cinco princípios ativos (levamisol, albendazol, ivermectina, monepantel e closantel) utilizados nas vermifugação. Foram analisadas amostras fecais, em três momentos (antes, 7 e 14 dias após o tratamento) utilizando a técnica de Gordon e Withlock (OPG), processadas e calculadas pelas fórmulas Eficácia=(1-[OPGtratado/OPGcontrole])x100 e Redução de OPG = 100 x [OPGt0 – OPGtn/OPGt0 ]. Nos momentos sete e quatorze os grupos tratamentos diferiram significativamente (p< 0,05%) do momento zero, porém, os animais tratados com ivermectina no momento quatorze não apresentaram diferença significativa quando comparado ao grupo controle. No exame coproparasitológico os gêneros mais frequentes foram Haemonchus e Trichostrongylus. Na primeira propriedade o monepantel e o albendazol demonstraram os melhores resultados de redução de OPG, na segunda propriedade o levamisol, closantel e monepantel apresentaram resultados expressivos quando comparado aos demais fármacos e na terceira propriedade os fármacos que tiveram melhores resultados de redução de OPG foram levamisol e monepantel. Nas propriedades A, B e C, foram diagnosticadas populações de nematoides resistentes a ivermectina. Nas propriedades B e C, foram diagnosticadas populações de nematoides resistentes a albendazol. 

Numeracy and COVID-19: Examining interrelationships between numeracy, health numeracy and behaviour

During the COVID-19 pandemic, people across the globe have been exposed to large amounts of statistical data. Previous studies have shown that individuals mathematical understanding of health-related information affects their attitudes and behaviours. Here, we investigate the relation between (i) basic numeracy, (ii) COVID-19 health numeracy, and (iii) COVID-19 health-related attitudes and behaviours. An online survey measuring these three variables was distributed in Canada, the United States (US) and the United Kingdom (UK) (n = 2032). In line with predictions, basic numeracy was positively related to COVID-19 health numeracy. However, predictions, neither basic numeracy nor COVID-19 health numeracy was related to COVID-19 healthrelated attitudes and behaviours (e.g. follow experts recommendations on social distancing, wearing masks etc.). Multi-group analysis was used to investigate mean differences and differences in the strength of the correlation across countries. Results indicate there were no between-country differences in the correlations between the main constructs but there were between-country differences in latent means. Overall, results suggest that while basic numeracy is related to one s understanding of data about COVID-19, better numeracy alone is not enough to influence a population s health-related attitudes about disease severity and to increase the likelihood of following public health advice

Nonsymbolic and symbolic magnitudes processing in children with mathematical difficulties

Exportado OPUSMade available in DSpace on 2019-08-14T12:25:09Z (GMT). No. of bitstreams: 1 starling_alves_thesis_final.pdf: 2038713 bytes, checksum: 18149520148642fbdbb9f753e7ea6cc0 (MD5) Previous issue date: 10Há um debate persistente na literatura quanto aos mecanismos relacionados a déficits específicos das dificuldades na matemática (MD). Por um lado, a hipótese do déficit central (core deficit) assume que crianças com MD apresentam dificuldades em processar e manipular magnitudes não-simbólicas. Por outro lado, a hipótese do transtorno de acesso propõe que crianças com MD apresentam habilidades de processamento de magnitudes nãosimbólicas preservadas, mas dificuldades em associar magnitudes simbólicas às suas representações analógicas correspondentes. Essa dissertação de mestrado investigou o desempenho de crianças com MD no processamento não-simbólico e simbólico de magnitudes, bem como a associação entre essas habilidades e o desempenho na matemática. No primeiro estudo, crianças com MD foram comparadas a pares com desempenho típico (TA) quanto a tempo de reação (RT), acurácia, efeito de distância e fração de Weber calculados em tarefas de comparação de magnitudes numéricas não-simbólicas e simbólicas. Crianças com MD apresentaram dificuldades no processamento de magnitudes nãosimbólicas, mas não no simbólico. Por fim, tanto o processamento simbólico de magnitudes quanto o não-simbólico foram preditores do desempenho na matemática em crianças com TA, mas não com MD. No segundo estudo, crianças com MD e TA foram comparadas quanto ao processamento não-simbólico de magnitudes e ao processamento de numerais com dois dígitos. Além disso, a relação entre o processamento numérico e as habilidades de aritmética e transcodificação numérica foi investigada. Crianças com MD e TA apresentaram dificuldades no processamento de magnitudes não-simbólicas e de números de dois-dígitos, e ambas as tarefas foram associados ao desempenho aritmético e na transcodificação numérica. De forma geral, os resultados do primeiro e do segundo estudo corroboram a hipótese do déficit central, e reforçam a importância do processamento numérico para o desempenho na matemáticaThere is a persistent debate in the literature on the mechanisms related to specific deficits in Mathematical Difficulties (MD). The core deficit hypothesis states that children with MD present difficulties to process and manipulate nonsymbolic magnitudes. On the other hand, the access deficit hypothesis proposes that children with MD present intact nonsymbolic magnitude processing abilities, but an impaired capacity to link symbolic numbers to their correspondent analog representations. This master's thesis investigated the performance of children with MD in nonsymbolic and symbolic magnitude processing, and the association of these abilities to math achievement. In the first study, children with MD were compared to typical achievement (TA) peers in nonsymbolic and symbolic magnitude comparison tasks, indexed by reaction time, accuracy, distance effect and Weber fraction. Children with MD presented difficulties in the nonsymbolic but not in the symbolic magnitude processing. Finally, both symbolic and nonsymbolic magnitude processing predicted the math achievement of TA, but not MD children. In the second study, children with MD and TA were compared regarding nonsymbolic magnitude processing and two-digit number processing and the relationship between these abilities and arithmetic and numerical transcoding skills was investigated. Children with MD presented difficulties in nonsymbolic and two-digit number processing, and both abilities were associated to math achievement and numerical transcoding skills. Overall, results of the first and the second studies support the core deficit hypothesis, and reinforce the importance of numerical processing for math achievemen

In search of the moral-psychological and neuroevolutionary basis of political partisanship

ABSTRACT In many countries, a radical political divide brings several socially relevant decisions to a standstill. Could cognitive, affective and social (CAS) neuroscience help better understand these questions? The present article reviews the moral-psychological and neuroevolutionary basis of the political partisanship divide. A non-systematic literature review and a conceptual analysis were conducted. Three main points are identified and discussed: 1) Political partisan behavior rests upon deep moral emotions. It is automatically processed and impervious to contradiction. The moral motifs characterizing political partisanship are epigenetically set across different cultures; 2) Political partisanship is linked to personality traits, whose neural foundations are associated with moral feelings and judgement; 3) Self-deception is a major characteristic of political partisanship that probably evolved as an evolutionary adaptive strategy to deal with the intragroup-extragroup dynamics of human evolution. CAS neuroscience evidence may not resolve the political divide, but can contribute to a better understanding of its biological foundations

The relationship between fluency and reading comprehension : evidence for brazilian portuguese speakers

Estudos recentes têm apontado a fluência de leitura como um importante preditor da compreensão de leitura. Contudo, poucos estudos investigaram a associação entre estas variáveis no português-brasileiro. No presente estudo, abordamos essa lacuna da literatura. Alunos do 2º ao 4º ano completaram um teste de fluência de leitura e um teste de compreensão de leitura. Os resultados demonstraram que há progresso nas habilidades de fluência e compreensão de leitura entre o 2º e o 4º ano, com progresso mais acentuado entre o 2º e o 3º ano. Além disso, os resultados mostraram que a associação entre fluência e compreensão de leitura foi significativa e positiva em todos os anos escolares, com magnitude acima de r = 0,6. Em conclusão, alunos com melhor fluência de leitura também apresentaram melhor compreensão de leitura, o que foi consistente nos diferentes anos escolares. Esses resultados corroboram resultados observados anteriormente em outros estudos nacionais e internacionais. É importante notar que os resultados do presente estudo contribuem com a prática ao sugerir que a promoção da fluência de leitura na sala de aula pode levar ao desenvolvimento de melhor compreensão de leitura.Recently, studies have found that reading fluency is an important predictor of reading comprehension. However, only a few studies have investigated the association between these factors in Brazilian-Portuguese. In the present study, we addressed this literature gap. 2nd to 4th-grade students completed a fluency task and a reading comprehension task. The results showed progress in fluency and reading comprehension skills from 2nd to 4th grade, with increased progress from 2nd to 3rd grade. Furthermore, results showed that the association between reading fluency and comprehension was significant and positive in all grades, with magnitude greater than r = 0.6. In conclusion, students with better reading fluency also had better reading comprehension, which was consistent across the different grades. These results corroborate results previously observed in national and international studies. Importantly, the results from the present study contribute to practice, suggesting that promoting reading fluency in the classroom may lead to development of better reading comprehension skills

Heterogeneidade Cognitiva nas Dificuldades de Aprendizagem da Matemática: Uma Revisão Bibliográfica

O progresso tecnológico e econômico de um país associa-se a melhorias na qualidade de vida à custa de uma demanda crescente do desempenhocognitivo e acadêmico da população. As dificuldades de aprendizagem da matemática (DAM) representam um risco, diminuindo potencialmenteo capital cognitivo de uma sociedade. Os diagnósticos e intervenções neuropsicológicos melhoram potencialmente o funcionamento cognitivo e obem-estar dos indivíduos. Pesquisas são necessárias para um planejamento efetivo e equitativo de políticas públicas. Os critérios diagnósticos atuaisdas dificuldades de aprendizagem são estatísticos e arbitrários, resultando em uma heterogeneidade clínica e em um alto índice de comorbidades.Neste artigo, foram analisados, através de uma revisão de literatura, os possíveis mecanismos cognitivos envolvidos nas DAM e em outrosdistúrbios relacionados. Conclui-se que o processamento fonológico, a memória de trabalho, o processamento visoespacial e o senso numéricosão domínios potencialmente subjacentes às DAM. Mais estudos longitudinais e integrativos que avaliem simultaneamente a contribuição destesfatores são necessários

From one half to 12th: acquisition of fraction writing in adult education program students and children

Learning fractions is essential for academic and daily life success. A critical first step in acquiring fractions is learning to transcode them (e.g., writing ½ when hearing “one half”). However, little is known about how students master fraction transcoding. We addressed this gap by assessing fraction writing in two groups of Brazilian students with limited education: adults in the first year of an adult education program (AEP-1) and 2nd graders. Both groups made frequent transcoding errors. Errors were classified into three categories, Syntactic: correct numerator/denominator values with an incorrect notation (12th for “one half”); Lexical: incorrect numerals with the correct notation (⅓ for “one half”); Combined: incorrect numerals and notation (15th for “one-half”). AEP-1 students’ performance was strongly bimodal: those with weak fraction writing skills made predominantly syntactic errors, whereas those with strong fraction writing skills made mostly lexical errors. Second graders did not transcode any fractions correctly making exclusively syntactic or combined errors. Approximately half the AEP-1 students with the lowest levels of schooling (&lt; 3 years) succeeded in writing fractions, suggesting an important role of informal experiences. In the early stages of learning fractions transcoding, students know how to write whole numbers, but do not yet know fractions syntax, leading to the preponderance of syntactic errors. As students learn fractions syntax, they make infrequent, predominantly lexical, errors. We conclude by proposing a model of fraction writing development that incorporates formal and informal learning experiences, executive functions, and phonemic awareness to explain the mastery of this important skill

In how many ways is the approximate number system sssociated with exact calculation?

The approximate number system (ANS) has been consistently found to be associated with math achievement. However, little is known about the interactions between the different instantiations of the ANS and in how many ways they are related to exact calculation. In a cross-sectional design, we investigated the relationship between three measures of ANS acuity (non-symbolic comparison, non-symbolic estimation and non-symbolic addition), their cross-sectional trajectories and specific contributions to exact calculation. Children with mathematical difficulties (MD) and typically achieving (TA) controls attending the first six years of formal schooling participated in the study. The MD group exhibited impairments in multiple instantiations of the ANS compared to their TA peers. The ANS acuity measured by all three tasks positively correlated with age in TA children, while no correlation was found between non-symbolic comparison and age in the MD group. The measures of ANS acuity significantly correlated with each other, reflecting at least in part a common numerosity code. Crucially, we found that non-symbolic estimation partially and non-symbolic addition fully mediated the effects of non-symbolic comparison in exact calculation