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Stroke is a neurological syndrome that usually causes a loss of voluntary control of lower/upper body movements, making it difficult for affected individuals to perform Activities of Daily Living (ADLs). Brain-Computer Interfaces (BCIs) combined with robotic systems, such as Motorized Mini Exercise Bikes (MMEB), have enabled the rehabilitation of people with disabilities by decoding their actions and executing a motor task. However, Electroencephalography (EEG)-based BCIs are affected by the presence of physiological and non-physiological artifacts. Thus, movement discrimination using EEG become challenging, even in pedaling tasks, which have not been well explored in the literature. In this study, Common Spatial Patterns (CSP)-based methods were proposed to classify pedaling motor tasks. To address this, Filter Bank Common Spatial Patterns (FBCSP) and Filter Bank Common Spatial-Spectral Patterns (FBCSSP) were implemented with different spatial filtering configurations by varying the time segment with different filter bank combinations for the three methods to decode pedaling tasks. An in-house EEG dataset during pedaling tasks was registered for 8 participants. As results, the best configuration corresponds to a filter bank with two filters (8-19 Hz and 19-30 Hz) using a time window between 1.5 and 2.5 s after the cue and implementing two spatial filters, which provide accuracy of approximately 0.81, False Positive Rates lower than 0.19, andKappaindex of 0.61. This work implies that EEG oscillatory patterns during pedaling can be accurately classified using machine learning. Therefore, our method can be applied in the rehabilitation context, such as MMEB-based BCIs, in the future.

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The degree of quality of thermoplastic injection-molded parts can be established based on their weight, appearance, and defects. However, the conditions of the injection process may induce effects on the mechanical performance of the injected parts, and the residual stresses can cause cracks or early failures when an external load or force is applied. To evaluate these mechanical behaviors, different experimental techniques have been reported in the literature, where digital photoelasticity has stood out both for being a non-contact technique and for achieving quantitative results through sophisticated computational algorithms. Against this background, our proposal consists of analyzing the overall residual stress distribution of parts injected under different molding conditions by using digital photoelasticity. In this case, the specimens are subjected to bending strength tests to identify possible effects of the injection process conditions. The findings show that, at mold temperatures of 80 °C, flow-induced residual stresses increase with packing pressure. However, these internal stress levels do not affect the external load applied by the mechanical bending test, while the mass injected at higher levels of packing pressure helps to increase the bending strength of the injected part. At lower mold temperatures (50 °C), the mechanical strength of the injected part is slightly reduced, possibly due to a lower effect of the packing pressure.

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Heterogeneity plays an important role in diversifying neural responses to support brain function. Adult neurogenesis provides the dentate gyrus with a heterogeneous population of granule cells (GCs) that were born and developed their properties at different times. Immature GCs have distinct intrinsic and synaptic properties than mature GCs and are needed for correct encoding and discrimination in spatial tasks. How immature GCs enhance the encoding of information to support these functions is not well understood. Here, we record the responses to fluctuating current injections of GCs of different ages in mouse hippocampal slices to study how they encode stimuli. Immature GCs produce unreliable responses compared to mature GCs, exhibiting imprecise spike timings across repeated stimulation. We use a statistical model to describe the stimulus-response transformation performed by GCs of different ages. We fit this model to the data and obtain parameters that capture GCs' encoding properties. Parameter values from this fit reflect the maturational differences of the population and indicate that immature GCs perform a differential encoding of stimuli. To study how this age heterogeneity influences encoding by a population, we perform stimulus decoding using populations that contain GCs of different ages. We find that, despite their individual unreliability, immature GCs enhance the fidelity of the signal encoded by the population and improve the discrimination of similar time-dependent stimuli. Thus, the observed heterogeneity confers the population with enhanced encoding capabilities.

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Human-machine interfaces (HMIs) can be used to decode a user's motor intention to control an external device. People that suffer from motor disabilities, such as spinal cord injury, can benefit from the uses of these interfaces. While many solutions can be found in this direction, there is still room for improvement both from a decoding, hardware, and subject-motor learning perspective. Here we show, in a series of experiments with non-disabled participants, a novel decoding and training paradigm allowing naïve participants to use their auricular muscles (AM) to control two degrees of freedom with a virtual cursor. AMs are particularly interesting because they are vestigial muscles and are often preserved after neurological diseases. Our method relies on the use of surface electromyographic records and the use of contraction levels of both AMs to modulate the velocity and direction of a cursor in a two-dimensional paradigm. We used a locking mechanism to fix the current position of each axis separately to enable the user to stop the cursor at a certain location. A five-session training procedure (20-30 min per session) with a 2D center-out task was performed by five volunteers. All participants increased their success rate (Initial: 52.78 ± 5.56%; Final: 72.22 ± 6.67%; median ± median absolute deviation) and their trajectory performances throughout the training. We implemented a dual task with visual distractors to assess the mental challenge of controlling while executing another task; our results suggest that the participants could perform the task in cognitively demanding conditions (success rate of 66.67 ± 5.56%). Finally, using the Nasa Task Load Index questionnaire, we found that participants reported lower mental demand and effort in the last two sessions. To summarize, all subjects could learn to control the movement of a cursor with two degrees of freedom using their AM, with a low impact on the cognitive load. Our study is a first step in developing AM-based decoders for HMIs for people with motor disabilities, such as spinal cord injury.

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Although time is a fundamental dimension of life, we do not know how brain areas cooperate to keep track and process time intervals. Notably, analyses of neural activity during learning are rare, mainly because timing tasks usually require training over many days. We investigated how the time encoding evolves when animals learn to time a 1.5 s interval. We designed a novel training protocol where rats go from naive- to proficient-level timing performance within a single session, allowing us to investigate neuronal activity from very early learning stages. We used pharmacological experiments and machine-learning algorithms to evaluate the level of time encoding in the medial prefrontal cortex and the dorsal striatum. Our results show a double dissociation between the medial prefrontal cortex and the dorsal striatum during temporal learning, where the former commits to early learning stages while the latter engages as animals become proficient in the task.

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Creativity, intelligence, and reading skills such as phonological awareness and decoding in reading can be critical to academic success, especially during childhood. Thus, this study aimed to characterize creativity, intelligence, phonological awareness, and reading decoding and verify possible relationships between creativity and these skills. The sample consisted of 75 children divided between the 1st, 2nd, and 3rd grades of municipal public schools in the Brazilian context. The results indicated the gradual evolution of creativity, intelligence, phonological awareness, and reading decoding in children from the 1st to the 3rd year, especially for the performance of the 3rd year. Correlations between creativity with intelligence and reading skills were also evidenced for all three classes, with the 3rd year with stronger correlations, which are promising results for these relationships. The study of creativity is still a recent field for empirical investigations and deserves future investigations for a better understanding of these constructs in this population.

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Decoding skills are crucial for literacy development and they tend to be acquired early in transparent languages, such as Brazilian Portuguese. It is essential to better understand which variables may affect the decoding process. In this study, we investigated the processes of decoding as a function of age of children who are exposed to a transparent language. To this end, we examined the effects of grade, stimulus type and stimulus extension on the decoding accuracy of children between the ages of six and 10 years who are monolingual speakers of Brazilian Portuguese. The study included 250 children, enrolled from the first to the fifth grade. A list of words and pseudowords of variable length was created, based on Brazilian Portuguese structure. Children assessment was conducted using the computer program E-prime® which was used to present the stimuli. The stimuli were programmed to appear on the screen in a random order and children were instructed to read them. The results indicate two important moments for decoding: the acquisition and the mastery of decoding skills. Additionally, the results highlight an important effect of the extent and type of stimuli and how it interacts with the school progress. Moreover, data indicate the multifactorial nature of decoding acquisition and the different interactions between variables that can influence this process. We discuss medium- and long-term implications of it, and possible individual and collective actions which can improve this process.

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Creativity, intelligence, and reading skills such as phonological awareness and decoding in reading can be critical to academic success, especially during childhood. Thus, this study aimed to characterize creativity, intelligence, phonological awareness, and reading decoding and verify possible relationships between creativity and these skills. The sample consisted of 75 children divided between the 1st, 2nd, and 3rd grades of municipal public schools in the Brazilian context. The results indicated the gradual evolution of creativity, intelligence, phonological awareness, and reading decoding in children from the 1st to the 3rd year, especially for the performance of the 3rd year. Correlations between creativity with intelligence and reading skills were also evidenced for all three classes, with the 3rd year with stronger correlations, which are promising results for these relationships. The study of creativity is still a recent field for empirical investigations and deserves future investigations for a better understanding of these constructs in this population. (AU)

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Multi-input multi-output (MIMO) transmission schemes have become the techniques of choice for increasing spectral efficiency in bandwidth-congested areas. However, the design of cost-effective receivers for MIMO channels remains a challenging task. The maximum likelihood detector can achieve excellent performance-usually, the best performance-but its computational complexity is a limiting factor in practical implementation. In the present work, a novel MIMO scheme using a practically feasible decoding algorithm based on the phase transmittance radial basis function (PTRBF) neural network is proposed. For some practical scenarios, the proposed scheme achieves improved receiver performance with lower computational complexity relative to the maximum likelihood decoding, thus substantially increasing the applicability of the algorithm. Simulation results are presented for MIMO-OFDM under 5G wireless Rayleigh channels so that a fair performance comparison with other reference techniques can be established.

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Whether subtle differences in the emotional context during threat perception can be detected by multi-voxel pattern analysis (MVPA) remains a topic of debate. To investigate this question, we compared the ability of pattern recognition analysis to discriminate between patterns of brain activity to a threatening versus a physically paired neutral stimulus in two different emotional contexts (the stimulus being directed towards or away from the viewer). The directionality of the stimuli is known to be an important factor in activating different defensive responses. Using multiple kernel learning (MKL) classification models, we accurately discriminated patterns of brain activation to threat versus neutral stimuli in the directed towards context but not during the directed away context. Furthermore, we investigated whether it was possible to decode an individual's subjective threat perception from patterns of whole-brain activity to threatening stimuli in the different emotional contexts using MKL regression models. Interestingly, we were able to accurately predict the subjective threat perception index from the pattern of brain activation to threat only during the directed away context. These results show that subtle differences in the emotional context during threat perception can be detected by MVPA. In the directed towards context, the threat perception was more intense, potentially producing more homogeneous patterns of brain activation across individuals. In the directed away context, the threat perception was relatively less intense and more variable across individuals, enabling the regression model to successfully capture the individual differences and predict the subjective threat perception.

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Antecedentes: La Descodificación Biológica propone la correspondencia entre el estrés ante una situación desbordante y la aparición de síntomas. La ciencia ha logrado profundizar en los componentes biológicos de los trastornos del desarrollo que podrían explicar lo queocurre en algunos preceptos de esta teoría. Objetivo: Determinar a partir de la revisión de literatura científica, la relación entre el estrés y algunas hormonas, con las alteraciones craneofaciales. Materiales y métodos: Se realizó una búsqueda en SciELO, PubMed y SCOPUS buscando artículos relacionados conel estrés, trastornos fisiológicos y esqueléticos y la hormona de crecimiento. Resultados: Se encontraron 17 artículos que relacionan el estrés con alteraciones fisiológicas, 18 artículos que muestran del el papel de los el estrés en el sistema nervioso central y la alteración de la hormona de crecimiento, además 16 artículos que relacionan la hormona de crecimiento con alteraciones esqueléticas craneofaciales. Conclusión: Se encontró evidencia que muestran cómo algunos supuestos de la teoría de la "Descodificación biológica" pueden ser explicados a partir del papel del estrés y de los estresores que podrían estimular respuestas a nivel del sistema nervioso central y llevar a cambios en estructuras óseas en pacientes en periodo de crecimiento o maduración ósea.

Background: Biological Decoding proposes the correspondence between stress in an overwhelming situation and the appearance of symptoms. Science has managed to investigate into the biological components of developmental disorders that could explain what happens in some precepts of this theory. Objective: To determine from the review of scientific literature, the relationship between stress and some hormones, with craniofacial alterations.Materials and methods: A search was carried out in SciELO, PubMed and SCOPUS looking for articles related to stress, physiological and skeletal disorders and growth hormone. Results: 17 articles were found that relate stress with physiological alterations, 18 articles that show the role of stress in the central nervous system and alteration of growth hormone, in addition 16 articles that relate growth hormone with alterations craniofacial skeletal. Conclusion: Evidence was found that shows how some assumptions of the "biological decoding" theory can be explained from the role of stress and stressors that could stimulate responses at the level of the central nervous system and lead to changes in bone structures in patients in a period of bone growth or maturation.

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El desarrollo de la lectura depende de dos mecanismos lingüísticos: la decodificación fonológica y la compresión de texto. Sin embargo, el efecto de ambos mecanismos puede variar según dos características: tipo de idioma (transparente vs. opaco) y experiencia lectora. Desde esta posición, se realizó un estudio longitudinal para determinar el efecto de la habilidad fonológica y léxica en la lectura durante 3 años de experiencia lectora en el idioma español. En el análisis se controló el efecto de la Memoria Verbal y la Inteligencia. Participaron 156 niños de 1er grado de dos escuelas primarias de Cienfuegos, Cuba. Al principio del 1er grado, se aplicaron cuatro pruebas: Vocabulario, Rimas de Sílabas, Memoria Verbal e Inteligencia. Al final del 1er grado, los niños se re-evaluaron con una prueba de fluidez lectora. Esa misma población se re-evaluó al final de 2do y 3er grado con otra prueba: Fluidez de Lectura, Segmentación Fonológica, Síntesis Fonemática Auditiva, Síntesis Fonemática Visual y Vocabulario de Peabody. Según los resultados, un año de experiencia de lectura en el idioma español es suficiente para obtener un desarrollo semántico significativo en los niños. Tres años de experiencia de lectura en el idioma español no es suficiente para indicar una automatización del mecanismo de decodificación fonológica.

The development of reading depends on two linguistic mechanisms: phonological decoding and reading compression. However, the effect of both mechanisms can vary according to the characteristics of the language (transparent vs. opaque) and reading experience (2 or 4 years of educational instruction). From this position, a longitudinal study was conducted to determine the effect of phonological and lexical ability on reading during 3 years of reading experience in the Spanish language. In the analysis, the effect of Verbal Memory and Intelligence was controlled (Raven Test). 156 children of first grade participated from two primary schools of Cienfuegos, Cuba. At the beginning of the 1st grade, four tests were applied: Vocabulary, Syllable Rhymes, Verbal Memory and Intelligence. At the end of the 1st grade, children were re-evaluated with a Reading Fluency Test. That same population was re-evaluated at the end of 2nd and 3rd grade for Reading Fluency, Phonological Segmentation, Phonetic Auditory Synthesis, Phonetic Visual Synthesis, and Peabody Vocabulary. According to the results, one year of reading experience in the Spanish language is sufficient to obtain a significant semantic development in the children. Three years of reading experience in the Spanish language is not enough to indicate an automation of the phonological decoding mechanism.

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In the last decades, a series of studies has explored the role of morphological awareness on reading comprehension. Path analysis studies performed in English have shown that morphological awareness benefits reading comprehension both directly and indirectly, through word decoding. This issue has seldom been explored in Spanish. The aim of this study was to replicate in Spanish the results previously found in English. We used path analysis to assess three alternative models of the relationship between morphological awareness, word decoding and reading comprehension in 4th grade Spanish-speaking children. Contrary to English, we found that morphological awareness benefits reading comprehension only directly. We conclude that in Spanish, in which accurate and fluent pronunciation of written words can be achieved through grapheme-to-phoneme conversion rules, morphological awareness does not help the correct pronunciation of words. Thus, morphological awareness is not relevant for word decoding in Spanish but is related to reading comprehension since this type of morphological knowledge provides access to the semantic and syntactic information of new words.

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A large body of research shows that performing tests is more beneficial for the retention of studied materials than restudying those materials, a phenomenon termed "testing-effect". A contemporary debate on the testing effect literature concerns whether the benefits of tests are equivalent for individuals with different cognitive skills, as the capacity to decode written words, for example. In the current study, we approached this issue in two experiments by examining whether testing is equally beneficial for children with diverse visual word decoding skills. To achieve this goal, we recruited sixth and fourth grade children (experiments 1 and 2, respectively) and administered a reading aloud task to assess their visual word recognition skills, and administered a memory task about an encyclopedic text to promote the testing effect. Memory for the restudied/tested contents of the encyclopedic text were probed after a seven-day interval, and although children from both experiments showed robust testing effects, such effects were not associated with their visual word decoding skills. These findings suggest that children with diverse word decoding skills can be benefited by retrieval practice.

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Los niños con TEL son considerados un grupo de riesgo para el aprendizaje del lenguaje escrito, dado que sus dificultades lingüísticas pueden influir en su desempeño en comprensión lectora, aunque esto no necesariamente ocurre en todos los niños con TEL. El objetivo de este estudio es comparar el desempeño en las habilidades lingüísticas y decodificación entre niños con TEL que se agruparon según la presencia o ausencia de dificultades en comprensión lectora. La muestra estuvo constituida por 60 niños con TEL de primer año básico, 42 de ellos con problemas de comprensión lectora y 18 niños que no presentaban dificultad en este aspecto. Se evaluaron habilidades lectoras (decodificación y comprensión lectora) y habilidades lingüísticas (conciencia fonológica, vocabulario y discurso narrativo expresivo y comprensivo). Los resultados muestran que no existen diferencias estadísticamente significativas en las habilidades lingüísticas entre niños con y sin dificultades de comprensión lectora. En cuanto a la decodificación, se observa un rendimiento significativamente inferior en el grupo de niños con dificultades de comprensión lectora. En este grupo, conciencia fonológica y decodificación están altamente correlacionadas con la comprensión lectora, mientras que estas mismas variables no se correlacionan en los niños sin problemas de comprensión lectora.

Children with Specific Language Impairment (SLI) are deemed to be a group at risk in learning written language. Their linguistic deficit may impact on their reading comprehension performance, although this not the case for all children with SLI. The aim ofthis study is to observe the possible differences in linguistic and decoding skills in children with SLI with and without reading comprehension problems. The sample consisted of 60 first grade children with SLI, of which 42 are poor comprehenders and 18 are good comprehenders. Reading skills (decoding and reading comprehension) and linguistic skills (phonological awareness, vocabulary as well as expressive and comprehensive narrative speech) were assessed. Results show that there are no statistically significant differences in linguistic skills between good comprehenders and poor comprehender. Significant differences were found for decoding, with children with reading comprehension problems performing significantly lower than good comprehenders. In the group of children with reading comprehension problems, phonological awareness and decoding highly correlate with reading comprehension, while the very same variables have no correlation among children with good reading comprehension.

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El objetivo del presente estudio fue describir el desempeño en decodificación y en comprensión lectora de escolares con Trastorno Específico del Lenguaje (TEL). Para ello, se trabajó con 58 niños de 2do básico, distribuidos en dos grupos: uno de 29 escolares con Trastorno Específico del Lenguaje (TEL) y otro de 29 escolares con desarrollo típico (DT). Las habilidades evaluadas fueron decodificación y comprensión lectora. Los resultados generales mostraron que el grupo con TEL presentó un menor desempeño que los niños con DT en ambas habilidades lectoras. Los menores con TEL tendieron a mostrar un mejor rendimiento en decodificación que en comprensión lectora. Respecto a la decodificación, los resultados mostraron que los niños con TEL lograban decodificar palabras comunes y trisilábicas. En cuanto a comprensión lectora, comprendían frases, oraciones y textos. Sin embargo, en el nivel del texto evidenciaron dificultades para responder las preguntas inferenciales y en el reconocimiento de la idea central.

This study was conducted to describe the reading performance of schoolers with Specific Language Impairment (SLI), observing their decoding skills and reading comprehension. A sample of 58 children of a second-grade primary school was studied, evenly grouped in two conditions: SLI and TLD (Typical Language Development). General results show that children with SLI perform lower than children with TLD on decoding and reading comprehension. Results for decoding skills showed that SLI children were able to decode trisyllabic words and common words. As for reading comprehension abilities, children were able to understand phrases, complete sentences, and give a proper title to the texts they read.

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Abstract This paper reports the performance of a representative sample of 747 students (52.5% female), from 2nd to 5th year of elementary education from private and public (83.8%) schools of Sao Paulo city. The children performed the Form A of Word Reading and Spelling Task (WRST) containing 48 low-frequency words presented in a card. Data were analyzed using models of Item Response Theory. We observed high levels of accuracy. The analysis selected 24 items, which presented low to moderate discrimination and difficulty indices. There were mean differences between grades, but not sex or school type. We report percentile norms for the grades for the WRST´S (Form) Reduced Version. The results support preceding studies with the word decoding tasks in Brazilian Portuguese, which attested to the quasi-regular character of that language.

Resumo O estudo investiga o desempenho de uma amostra representativa de crianças (52,5% meninas) cursando do 2º ao 5º ano de escolas particulares e públicas (83,8%) de São Paulo (N = 747). As crianças leram em voz alta a Forma A da Prova de Leitura e de Escrita de Palavras (PLEP), constituída de 48 palavras de baixa frequência, apresentadas em um cartão. Os dados foram analisados utilizando modelos da Teoria de Resposta ao Item. Observaram-se altos índices de acurácia. Foram selecionados 24 itens, os quais apresentaram, em média, índices de discriminação e de dificuldade de baixos a moderados. Houve efeito de escolaridade, mas não de sexo ou tipo de escola. Normas em percentis foram reportadas para a versão reduzida da Forma A da PLEP. Os resultados condizem com estudos que utilizaram tarefas de decodificação de palavras no Brasil e atestam para o caráter quase-regular do idioma.

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A nomeação seriada rápida é utilizada para avaliar o acesso lexical. O trabalho relata um estudo de validação e normas para a Prova de Nomeação Rápida, composta por seis figuras que se repetem aleatoriamente em dois cartões (Parte A e Parte B). Uma amostra representativa de alunos do 2o ao 5o ano do Ensino Fundamental de escolas públicas e particulares de São Paulo-SP (N = 728) respondeu à Prova de Nomeação e realizou uma tarefa de leitura de palavras. O tempo de execução e o número de acertos foram computados. Conforme esperado: (1) ocorreu efeito de escolaridade para o tempo de execução e precisão; (2) houve menor precisão e maior tempo de execução para a Parte B; (3) as duas partes apresentaram correlações estatisticamente significantes (p < 0,05); (4) o tempo de execução e a precisão foram preditores da leitura. Os resultados fornecem evidências de validade para a tarefa criada.

Rapid naming tasks evaluate lexical access. We report a validity study and norms for the Rapid Automatized Naming Task, composed of six randomized pictures distributed on two cards (Part A and B). A representative sample of children from 2nd to 5th grades of elementary schools of Sao Paulo City (N = 728) was tested in the task and word recognition. Response time and accuracy were collected. As expected, the following evidences were observed: (1) grade effect for response time and accuracy, (2) response time and error rates were higher for Part B, (3) correlation between Part A and B was significant (p < 0.05), and (4) response time and accuracy predicted decoding ability. The results support different sources of validity evidence for the task.

La denominación en serie rápida es utilizada para evaluar el acceso al léxico. Este trabajo presenta resultados de validez y normas para la Prueba de Denominación Rápida, compuesta por seis figuras que se repiten aleatoriamente en dos tarjetas del test (Parte A y parte B). Una muestra representativa de alumnos de segundo a quinto año de Enseñanza Primaria de escuelas públicas y privadas de San Pablo-SP, fue evaluada (N=728) con las tareas de velocidad de denominación y lectura de palabras. El tiempo de ejecución y total de aciertos fueron computados. Los resultados mostraron: 1) Efecto de la escolaridad para el tiempo de ejecución y precisión de la denominación; 2) Menor precisión y mayor tiempo de ejecución en la Parte B; 3) Correlaciones estadísticamente significativas entre las dos partes del test p < 0,05); 4) el tiempo de ejecución y la precisión fueron predictores de la lectura. Los resultados proporcionan evidencias de validez para la tarea creada.

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A nomeação seriada rápida é utilizada para avaliar o acesso lexical. O trabalho relata um estudo de validação e normas para a Prova de Nomeação Rápida, composta por seis figuras que se repetem aleatoriamente em dois cartões (Parte A e Parte B). Uma amostra representativa de alunos do 2o ao 5o ano do Ensino Fundamental de escolas públicas e particulares de São Paulo-SP (N = 728) respondeu à Prova de Nomeação e realizou uma tarefa de leitura de palavras. O tempo de execução e o número de acertos foram computados. Conforme esperado: (1) ocorreu efeito de escolaridade para o tempo de execução e precisão; (2) houve menor precisão e maior tempo de execução para a Parte B; (3) as duas partes apresentaram correlações estatisticamente significantes (p < 0,05); (4) o tempo de execução e a precisão foram preditores da leitura. Os resultados fornecem evidências de validade para a tarefa criada.

Rapid naming tasks evaluate lexical access. We report a validity study and norms for the Rapid Automatized Naming Task, composed of six randomized pictures distributed on two cards (Part A and B). A representative sample of children from 2nd to 5th grades of elementary schools of Sao Paulo City (N = 728) was tested in the task and word recognition. Response time and accuracy were collected. As expected, the following evidences were observed: (1) grade effect for response time and accuracy, (2) response time and error rates were higher for Part B, (3) correlation between Part A and B was significant (p < 0.05), and (4) response time and accuracy predicted decoding ability. The results support different sources of validity evidence for the task.

La denominación en serie rápida es utilizada para evaluar el acceso al léxico. Este trabajo presenta resultados de validez y normas para la Prueba de Denominación Rápida, compuesta por seis figuras que se repiten aleatoriamente en dos tarjetas del test (Parte A y parte B). Una muestra representativa de alumnos de segundo a quinto año de Enseñanza Primaria de escuelas públicas y privadas de San Pablo-SP, fue evaluada (N=728) con las tareas de velocidad de denominación y lectura de palabras. El tiempo de ejecución y total de aciertos fueron computados. Los resultados mostraron: 1) Efecto de la escolaridad para el tiempo de ejecución y precisión de la denominación; 2) Menor precisión y mayor tiempo de ejecución en la Parte B; 3) Correlaciones estadísticamente significativas entre las dos partes del test p < 0,05); 4) el tiempo de ejecución y la precisión fueron predictores de la lectura. Los resultados proporcionan evidencias de validez para la tarea creada.

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RESUMO

La comprensión lectora es un complejo proceso que se asienta en tres habilidades básicas interrelacionadas: la decodificación, el conocimiento léxico-semántico y los procesos de integración textual. Investigaciones previas han indicado que las dificultades en la comprensión lectora pueden deberse a la decodificación ineficaz, las carencias en el conocimiento léxico-semántico y los problemas para realizar inferencias. Los objetivos del trabajo que se informa fueron estudiar las relaciones entre las habilidades de la comprensión lectora y estudiar la contribución de las habilidades de decodificación y del conocimiento léxico-semántico, a la realización de inferencias textuales. Participaron 94 niños de escolaridad primaria de 8 a 10 años de edad. Se administraron las subpruebas de Identificación de Letras y de Procesos Léxicos de la Batería de Evaluación de los Procesos Lectores (Cuetos, Rodríguez, Ruano & Arribas, 2010), la adaptación del Subtest de Vocabulario de la Escala de Inteligencia de Wechsler para Niños de Contini, Figueroa, Cohen Imach y Coronel de Pace (2000) y las Tareas de Inferenciasde Cain y Oakhill (Canet Juric & Burin, 2006). Los resultados indicaron correlaciones moderadas a altas y significativas entre las habilidades lectoras. Las habilidades de decodificación y conocimiento léxico-semántico explicaron el 51% de las inferencias, pero la única que realizó una contribución significativa fue el conocimiento léxico. En el caso de las inferencias puente, el conjunto de las variables explicó el 48% de éstas y en el de las elaborativas, el 45%. En ambos casos, el único predictor que hizo una contribución significativa fue el conocimiento léxico. En conclusión, las habilidades lectoras se hallan relacionadas y el vocabulario es un componente básico para las habilidades de mayor nivel como las inferencias.

Reading comprehension is a complex process which lies upon three interrelated basic skills: decoding, lexical semantic knowledge and word to-text integration processes. Decoding entails the reader’s ability to recognize grapheme-phoneme correspondence. Lexical semantic knowledge refers to the knowledge of words in a given language, and it includes both word identification, i.e., visual processing of the graphemes’ shapes and lexical activation; and semantic awareness, i.e., knowledge of meaning. Decoding and lexical semantic knowledge are deemed as pertaining to a lower level in relation to integration, in which category we include such skills as inference - generation. Previous research, notably in England, the United States of America and Argentina, has shown that difficulties in reading comprehension may be due to faulty decoding, poor lexical semantic knowledge and inference making failures. Although each of these skills is necessary to achieve comprehension, none of them alone can guarantee it. It is considered that decoding and lexical knowledge are associated skills, and influence each other. The effects of decoding in text comprehension are mediated by knowledge about the meaning of words and the effects of comprehension in decoding depend on the achievement of sufficient word meanings. Thus, the aims of this paper were to study the relations among reading comprehension skills and to study how decoding skills and lexical semantic knowledge contribute to inference-making generation. In broad terms, the hypotheses were reading comprehension skills are interrelated and decoding skills and lexical knowledge are significant predictors of inference-making generation. This survey was conducted among 94 primary school children of an average age of 8 to 10 years old. They were given the Letter Recognition and Lexical Processes Tests from the PROLEC Test Battery, the Vocabulary Subtest from Wechsler Intelligence Scale for Children (WISC-III) and the Inference-making Ability Assessments from Cain and Oakhill (Canet Juric & Burin, 2006). Results have shown that in the decoding assessment, the highest number of errors and correct answers are found in pseudo word reading. Regarding lexical knowledge, the highest average of right answers is found in word reading. As regards word-to-text integration, the average number of inferences incorrectly drawn is 14.62. Since the tests we used measured right and wrong answers, indices of decoding and lexical knowledge were created. Moreover, our findings suggest significant and moderate-to-strong relations among reading comprehension skills. Decoding skills and lexical semantic knowledge have accounted for 51% of inferences. However, lexical knowledge alone has made the most significant contribution. The set of variables has accounted for 48% of coherence inferences and 45% of elaborative inferences. The only significant predictor of both types of inference-making was lexical knowledge. To conclude, as posited by international research and our first hypothesis, comprehension skills are interrelated. Taking into consideration our second hypothesis, our findings suggest that comprehension skills account for inference-making generation and that lexical knowledge reveals itself as a predictor of the children’s potential ability for inference-making. In other words, vocabulary is a basic component of more complex skills such as inference. This is consistent with what international research suggests. As regards the performance of the general sample in the assessed comprehension skills, it resembles that of the child population of the same age, surveyed in Tucumán and in. Taking into consideration the way in which comprehension skills relate to and affect each other could allow us to develop intervention programs which would help improve the performance of children who demonstrate text comprehension difficulties.