Machine Learning Enabled Decoding of Color-coded Droplet Arrays and Its Application in Multiplex Digital Nucleic Acid Analysis / 分析化学

To address the throughput limitations of digital nucleic acid analysis,a tricolor combination-based droplet coding technique was developed to achieve multiplex digital nucleic acid analysis with flexible throughput expansibility.To improve the analysis efficiency,a machine learning-based method was further developed for automatic decoding of color-coded droplet array.The machine learning algorithm empowered the computer program to automatically extract the color-position-quantity information of the droplets.By correlating this color-position-quantity of droplets before and after nucleic acid amplification,the proportion of positive droplets for each target was rapidly determined.This droplet decoding strategy was applied to multiplex digital nucleic acid analysis.The experimental results demonstrated that this droplet decoding method was fast and accurate,with a decoding process completed within 2 min.Furthermore,the droplet identification accuracy exceeded 99%.Additionally,the obtained nucleic acid quantification results exhibited a good correlation(R2＞0.99)with those reported by a commercial digital PCR instrument.

The posture decoding technique can improve the pelvis carriage and lumbar motion of patients with lower crossed syndrome, relieving back pain and relaxing the back muscles / 中华物理医学与康复杂志

Objective:To observe the clinical effectiveness of manual therapy based on posture decoding for patients with lower crossed syndrome (LCS).Methods:Thirty-six LCS patients were randomly divided into an observation group and a control group, each of 18. The observation group received manual therapy based on posture decoding, while the control group was treated with proprioceptive neuromuscular facilitation (PNF), both in 20min sessions, once a week for 4 weeks. Before the experiment, after one, two and four weeks of treatment and followed-up 4 and 8 weeks later, both groups were evaluated using a visual analogue scale (VAS), the Oswestry Disability Index (ODI) and finger-floor distance (FFD). Anterior pelvic tilt angles (ASIS-PSISs), sacral slopes (SS), lumbar curve index (LCI) and surface EMG flexion-relaxation ratios (FRRs) were also recorded from both groups before and after the treatment.Results:After one and four weeks of the treatment, the average VAS, ODI, and FFD had decreased significantly in both groups, with all significantly lower in the observation group, on average. At the final follow-up, the average VAS and ODI scores of both groups were significantly lower than before the treatment, with those of the observation group significantly lower than the control group′s averages. After 4 weeks of treatment significant differences were observed also in the group′s average ASIS-PSISs, SSs and LCIs compared with before the treatment. And right after the treatment the left and right surface electromyography FRRs of the observation group were significantly higher than those of the control group.Conclusion:Manual therapy based on posture decoding can significantly improve the pelvis forward angle and lumbar motion of LCS patients, relieving back pain and relaxing back muscles.

Recognition of high-frequency steady-state visual evoked potential for brain-computer interface / 生物医学工程学杂志

Coding with high-frequency stimuli could alleviate the visual fatigue of users generated by the brain-computer interface (BCI) based on steady-state visual evoked potential (SSVEP). It would improve the comfort and safety of the system and has promising applications. However, most of the current advanced SSVEP decoding algorithms were compared and verified on low-frequency SSVEP datasets, and their recognition performance on high-frequency SSVEPs was still unknown. To address the aforementioned issue, electroencephalogram (EEG) data from 20 subjects were collected utilizing a high-frequency SSVEP paradigm. Then, the state-of-the-art SSVEP algorithms were compared, including 2 canonical correlation analysis algorithms, 3 task-related component analysis algorithms, and 1 task discriminant component analysis algorithm. The results indicated that they all could effectively decode high-frequency SSVEPs. Besides, there were differences in the classification performance and algorithms' speed under different conditions. This paper provides a basis for the selection of algorithms for high-frequency SSVEP-BCI, demonstrating its potential utility in developing user-friendly BCI.

Key technology of brain-computer interaction based on speech imagery / 生物医学工程学杂志

Speech expression is an important high-level cognitive behavior of human beings. The realization of this behavior is closely related to human brain activity. Both true speech expression and speech imagination can activate part of the same brain area. Therefore, speech imagery becomes a new paradigm of brain-computer interaction. Brain-computer interface (BCI) based on speech imagery has the advantages of spontaneous generation, no training, and friendliness to subjects, so it has attracted the attention of many scholars. However, this interactive technology is not mature in the design of experimental paradigms and the choice of imagination materials, and there are many issues that need to be discussed urgently. Therefore, in response to these problems, this article first expounds the neural mechanism of speech imagery. Then, by reviewing the previous BCI research of speech imagery, the mainstream methods and core technologies of experimental paradigm, imagination materials, data processing and so on are systematically analyzed. Finally, the key problems and main challenges that restrict the development of this type of BCI are discussed. And the future development and application perspective of the speech imaginary BCI system are prospected.

From Parametric Representation to Dynamical System: Shifting Views of the Motor Cortex in Motor Control / 神经科学通报·英文版

In contrast to traditional representational perspectives in which the motor cortex is involved in motor control via neuronal preference for kinetics and kinematics, a dynamical system perspective emerging in the last decade views the motor cortex as a dynamical machine that generates motor commands by autonomous temporal evolution. In this review, we first look back at the history of the representational and dynamical perspectives and discuss their explanatory power and controversy from both empirical and computational points of view. Here, we aim to reconcile the above perspectives, and evaluate their theoretical impact, future direction, and potential applications in brain-machine interfaces.

A review of researches on decoding algorithms of steady-state visual evoked potentials / 生物医学工程学杂志

Brain-computer interface (BCI) systems based on steady-state visual evoked potential (SSVEP) have become one of the major paradigms in BCI research due to their high signal-to-noise ratio and short training time required by users. Fast and accurate decoding of SSVEP features is a crucial step in SSVEP-BCI research. However, the current researches lack a systematic overview of SSVEP decoding algorithms and analyses of the connections and differences between them, so it is difficult for researchers to choose the optimum algorithm under different situations. To address this problem, this paper focuses on the progress of SSVEP decoding algorithms in recent years and divides them into two categories-trained and non-trained-based on whether training data are needed. This paper also explains the fundamental theories and application scopes of decoding algorithms such as canonical correlation analysis (CCA), task-related component analysis (TRCA) and the extended algorithms, concludes the commonly used strategies for processing decoding algorithms, and discusses the challenges and opportunities in this field in the end.

Creativity and its relationship with intelligence and reading skills in children: an exploratory study

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)

Convolutional neural network based on temporal-spatial feature learning for motor imagery electroencephalogram signal decoding / 生物医学工程学杂志

With the advantage of providing more natural and flexible control manner, brain-computer interface systems based on motor imagery electroencephalogram (EEG) have been widely used in the field of human-machine interaction. However, due to the lower signal-noise ratio and poor spatial resolution of EEG signals, the decoding accuracy is relative low. To solve this problem, a novel convolutional neural network based on temporal-spatial feature learning (TSCNN) was proposed for motor imagery EEG decoding. Firstly, for the EEG signals preprocessed by band-pass filtering, a temporal-wise convolution layer and a spatial-wise convolution layer were respectively designed, and temporal-spatial features of motor imagery EEG were constructed. Then, 2-layer two-dimensional convolutional structures were adopted to learn abstract features from the raw temporal-spatial features. Finally, the softmax layer combined with the fully connected layer were used to perform decoding task from the extracted abstract features. The experimental results of the proposed method on the open dataset showed that the average decoding accuracy was 80.09%, which is approximately 13.75% and 10.99% higher than that of the state-of-the-art common spatial pattern (CSP) + support vector machine (SVM) and filter bank CSP (FBCSP) + SVM recognition methods, respectively. This demonstrates that the proposed method can significantly improve the reliability of motor imagery EEG decoding.

Deep Natural Image Reconstruction from Human Brain Activity Based on Conditional Progressively Growing Generative Adversarial Networks / 神经科学通报·英文版

Brain decoding based on functional magnetic resonance imaging has recently enabled the identification of visual perception and mental states. However, due to the limitations of sample size and the lack of an effective reconstruction model, accurate reconstruction of natural images is still a major challenge. The current, rapid development of deep learning models provides the possibility of overcoming these obstacles. Here, we propose a deep learning-based framework that includes a latent feature extractor, a latent feature decoder, and a natural image generator, to achieve the accurate reconstruction of natural images from brain activity. The latent feature extractor is used to extract the latent features of natural images. The latent feature decoder predicts the latent features of natural images based on the response signals from the higher visual cortex. The natural image generator is applied to generate reconstructed images from the predicted latent features of natural images and the response signals from the visual cortex. Quantitative and qualitative evaluations were conducted with test images. The results showed that the reconstructed image achieved comparable, accurate reproduction of the presented image in both high-level semantic category information and low-level pixel information. The framework we propose shows promise for decoding the brain activity.

La descodificación biológica y las alteraciones craneofaciales, una mirada desde las ciencias básicas / Biological decoding and craniofacial alterations, a view from basic sciences

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.

Decodificación fonológica y fluidez lectora: un estudio longitudinal / Phonological decoding and fluency reader: a longitudinal study

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.

Habilidades lingüísticas y decodificación en niños con trastorno específico del lenguaje con y sin dificultades de comprensión lectora / Linguistic skills and decoding among children with specific language impairment with and without reading comprehension difficulties

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.

Decodificación y comprensión lectora en escolares con trastorno específico del lenguaje / Decoding and reading comprehension in children with specific language impairment

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.

High-energy photon depth of interaction calculation based on light-sharing-window method / 医疗卫生装备

Objective To propose a method for high-energy photon 3D decoding of PET detector to decode reactive crystal position and calculate γ ray depth in the scintillating crystal. Methods Light transmitting windows were set between the crystal arrays, visible photon groups were guided to distribute in the photoelectric sensor array during a single event, and sensor signal intensity was regulated to realize position and depth decoding of the high-energy photon.Monte Carlo method was used to compare the designs of different light transmitting windows to determine the effects of the crystal surface treatment mode on the results. Experiments were executed for further verification. Results The experimental results had consistency with simulation ones;the signal received through the reaction crystal was always stronger than that through the adjacent, which could decode the reaction crystals; the relations between the depth of interaction (DOI) and energy differences of the photo sensors were monotonic with the changes of DOI,and thus could be used to calculate the DOI;when using single window,the DOI vs.Diff.Energy curves had two segments which were not desired for DOI measurement;crystals with rough surfaces were more desired since the qualities of their DOI vs.Diff.Energy curves were better;the dual window method had the best DOI vs.Diff.Energy curves in term of linearity.Conclusion The method can realize 3D decoding of the discrete crystal array,which improves the energy resolution of the PET system. [Chinese Medical Equipment Journal, 2018,39(5):22-28,63]

Comparison of decoding performance between spike and local field potential signals during goal-directed decision-making task of pigeons / 生物医学工程学杂志

Both spike and local field potential (LFP) signals are two of the most important candidate signals for neural decoding. At present there are numerous studies on their decoding performance in mammals, but the decoding performance in birds is still not clear. We analyzed the decoding performance of both signals recorded from nidopallium caudolaterale area in six pigeons during the goal-directed decision-making task using the decoding algorithm combining leave-one-out and -nearest neighbor (LOO- NN). And the influence of the parameters, include the number of channels, the position and size of decoding window, and the nearest neighbor value, on the decoding performance was also studied. The results in this study have shown that the two signals can effectively decode the movement intention of pigeons during the this task, but in contrast, the decoding performance of LFP signal is higher than that of spike signal and it is less affected by the number of channels. The best decoding window is in the second half of the goal-directed decision-making process, and the optimal decoding window size of LFP signal (0.3 s) is shorter than that of spike signal (1 s). For the LOO- NN algorithm, the accuracy is inversely proportional to the value. The smaller the value is, the larger the accuracy of decoding is. The results in this study will help to parse the neural information processing mechanism of brain and also have reference value for brain-computer interface.

Word Decoding Task: Item Analysis by IRT and Within-Group Norms / Tarefa de Decodificação: Análise de Itens pela TRI e Normas Intragrupo

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.

Prova de nomeação rápida de figuras para crianças: evidências de validade e normas intragrupo / Rapid automatized naming of pictures for children: validity studies and intra-group norms / Prueba de denominación rápida de figuras para niños: evidencias de validez y normas intragrupo

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.

Amplitude Modulation-based Electrical Stimulation for Encoding Multipixel Spatiotemporal Visual Information in Retinal Neural Activities

Retinal implants have been developed as a promising way to restore partial vision for the blind. The observation and analysis of neural activities can offer valuable insights for successful prosthetic electrical stimulation. Retinal ganglion cell (RGC) activities have been investigated to provide knowledge on the requirements for electrical stimulation, such as threshold current and the effect of stimulation waveforms. To develop a detailed ‘stimulation strategy’ for faithful delivery of spatiotemporal visual information to the brain, it is essential to examine both the temporal and spatial characteristics of RGC responses, whereas previous studies were mainly focused on one or the other. In this study, we investigate whether the spatiotemporal visual information can be decoded from the RGC network activity evoked by patterned electrical stimulation. Along with a thorough characterization of spatial spreading of stimulation current and temporal information encoding, we demonstrated that multipixel spatiotemporal visual information can be accurately decoded from the population activities of RGCs stimulated by amplitude-modulated pulse trains. We also found that the details of stimulation, such as pulse amplitude range and pulse rate, were crucial for accurate decoding. Overall, the results suggest that useful visual function may be restored by amplitude modulation-based retinal stimulation.

Relaciones entre decodificación, conocimiento léxico-semántico e inferencias en niños de escolaridad primaria / Relations between decoding, lexical-semantic knowledge and inferences in primary school children

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.

Há uma relação específica entre consciência morfológica e reconhecimento de palavras? / Is there a specific connection between morphological awareness and word recognition? / ¿Hay una relación específica entre consciencia morfológica y reconocimiento de palabras?

Estudos realizados em línguas alfabéticas mostram que a consciência morfológica - habilidade de refletir sobre os morfemas que compõem as palavras - está associada ao sucesso no reconhecimento e compreensão de palavras na leitura e na escrita. O português é uma língua com uma ortografia que se encontra no meio do espectro quando falamos da transparência nas correspondências entre letra e som. Em línguas transparentes, com correspondência grafema-fonema regulares, a consciência morfológica pode não ter o mesmo impacto na aquisição da escrita. Neste estudo investigamos se o processamento da morfologia derivacional em crianças do ensino fundamental contribui para leitura no português e se essa contribuição é independente da decodificação. Utilizou-se uma tarefa de spooneirismo e outra de subtração de fonemas para acessar a decodificação e o TDE para leitura de palavras. Os resultados mostram que a decodificação é uma habilidade muito importante na leitura e que a habilidade de refletir sobre os morfemas contribui para leitura e que essa contribuição é até certo ponto independente da consciência fonológica.

Studies carried out in alphabetic languages show that morphological awareness - the ability to reflect upon the word's morphemes - is related to the success in recognizing words and comprehension in reading and spelling. Portuguese is a language located in the middle of transparent letter-sound correspondence rules. In transparent languages, those with regular grapheme-phoneme correspondence rules, morphological awareness may not have the impact in written language acquisition. This study investigated whether derivational morphology processing contributes to reading in Portuguese in primary education and whether this contribution is independent of phonological decoding. A phoneme spooneirism task and another of phoneme subtraction task was used to access reading decoding and the TDE was used to assess reading recognition. The results show that decoding is a very important ability to learn to read and that the ability to reflect upon the morphemes of the words contributes to reading and that this contribution is, to a certain extent independent of phonological awareness.

Estudios realizados en lenguas alfabéticas señalan que la consciencia morfológica - la habilidad de reflexionar sobre los morfemas que componen las palabras - está asociada al éxito en el reconocimiento y comprensión de palabras tanto en la lectura como en la escritura. El portugués es una lengua con una ortografía que se encuentra a medio camino del espectro en lo que se refiere a la transparencia en términos de la correspondencia entre letras y sonidos. En lenguas transparentes, que tienen una correspondencia grafema-fonema regular, la conciencia morfológica puede no tener el mismo impacto en la adquisición de la escritura. En este estudio investigamos si el procesamiento de la morfología derivativa en niños de Enseñanza Básica contribuye para la lectura en lengua portuguesa, y si dicha contribución es independiente de la descodificación. Se utilizó una tarea de spoonerismo y otra de sustracción de fonemas para acceder a la descodificación además del TDE para la lectura de palabras. Los resultados señalan que la descodificación es una habilidad muy importante en lo que se refiere a la lectura y que la habilidad de reflexionar sobre los morfemas contribuye a la lectura además que dicha contribución es en cierta medida independiente de la consciencia fonológica.