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This study examined the relative contributions of phonological awareness, orthographic pattern recognition, and rapid letter naming to fluent word and connected-text reading within a dyslexic sample of 123 children in second and third grades. Participants were assessed on a variety of fluency measures and reading subskills. Correlations and hierarchical multiple regression analyses were carried out to explore these relationships. The results demonstrate that phonological awareness, rapid letter naming, and orthographic pattern recognition contribute to word-reading skills. Furthermore, rapid naming, orthographic pattern recognition, and word reading fluency moderately predict different dimensions of connected-text reading (i.e., rate, accuracy, and comprehension) whereas phonological awareness contributes only to the comprehension dimension of connected-text reading. The findings support the multidimensional nature of fluency in which the whole is more than its parts.

This article details a study which predicted that across a wide range of print sizes dyslexic reading would follow the same curve shape as skilled reading, with constant reading rates across large print sizes and a sharp decline in reading rates below a critical print size. It also predicted that dyslexic readers would require larger critical print sizes to attain their maximum reading speeds, following the letter position coding deficit hypothesis. Reading speed was measured across twelve print sizes ranging from Snellen equivalents of 20/12 to 20/200 letter sizes for a group of dyslexic readers in Grades 2 to 4 (aged 7 to 10 years), and for non-dyslexic readers in Grades 1 to 3 (aged 6 to 8 years). The groups were equated for word reading ability. Results confirmed that reading rate-by-print size curves followed the same two-limbed shape for dyslexic and non-dyslexic readers. Dyslexic reading curves showed higher critical print sizes and shallower reading rate-by-print size slopes below the critical print size, consistent with the hypothesis of a letter-position coding deficit. Non-dyslexic reading curves also showed a decrease of critical print size with age. A developmental lag model of dyslexic reading does not account for the results, since the regression of critical print size on maximum reading rate differed between groups.Developmental dyslexia, a learning disability specific to reading, affects an estimated 5% of children in school. Reading requires processing of both the visual information from the page and the linguistic information that the print represents. Over a century of research on causal factors in developmental dyslexia has emphasised either one or the other of these processes, beginning with theories of visual causation. Morgan (1896) coined the inability to read in children as 'congenital word blindness ', while Orton (1928) described the phenomenon of 'strephosymbolia' (twisted symbols), where children could read mirror-image writing more easily. The current view of dyslexia holds that reading failure is caused by a linguistic deficit in coding phonemes (individual speech sounds) within words, and thereby in accessing and manipulating these phonemic codes as required on a wide range of tasks (phonological processing) (Snowling, 2000). This view holds that a phonological processing deficit impedes a child's ability to develop phoneme awareness, to learn grapheme-phoneme correspondence rules, and to decode words (Liberman et al., 1974;Stanovich & Siegel, 1994). The theory accounts for many cases of developmental dyslexia, but there are individuals with dyslexia who do not demonstrate a severe phonological deficit (Wolf & Bowers, 1999;Lovett, Steinbach & Frijters, 2000). Also, remediation programmes aimed at training phonological skills are often but not entirely successful (Lyon & Moats, 1997;Torgesen, 2000). This suggests a need for alternative or additional accounts of causal factors in dyslexia. Recent evidence shows that subtle impairments in visual processing characterise some...

Both internal factors (e.g., nonverbal intelligence) and external factors (e.g., input quantity) are claimed to affect the rate of children's vocabulary development. However, it remains an open question whether these variables work similarly on bilingual children's dual language learning. The current paper examined this issue on 805 Singapore children (4 years, 1 month to 5 years, 8 months) who are learning English (societal language) and an ethnic language (Mandarin/Malay/Tamil). Singapore is a bilingual society; however, there is an inclination for English use at home in recent years, resulting in a discrepancy of input between English and ethnic languages in many families. In this study, internal and external factors were examined comprehensively with standardized tests and a parental questionnaire. Regression analysis was used to address the questions. There were statistically significant differences in language input quantity, quality, and output between English and ethnic language learning environments. Singapore children are learning English in an input-rich setting while learning their ethnic language in a comparatively input-poor setting. Multiple regressions revealed that while both sets of factors explained lexical knowledge in each language, the relative contribution is different for English and ethnic languages: internal factors explained more variance in English language vocabulary, whereas external factors were more important in explaining ethnic language knowledge. We attribute this difference to a threshold effect of external factors based on the critical mass hypothesis and call for special attention to learning context (input-rich vs. input-poor settings) for specific bilingual language studies.

Reading speed is commonly used as an index of reading fluency. However, reading speed is not a consistent predictor of text comprehension, when speed and comprehension are measured on the same text within the same reader. This might be due to the somewhat ambiguous nature of reading speed, which is sometimes regarded as a feature of the reading process, and sometimes as a product of that process. We argue that both reading speed and comprehension should be seen as the result of the reading process, and that the process of fluent text reading can instead be described by complexity metrics that quantify aspects of the stability of the reading process. In this article, we introduce complexity metrics in the context of reading and apply them to data from a self-paced reading study. In this study, children and adults read a text silently or aloud and answered comprehension questions after reading. Our results show that recurrence metrics that quantify the degree of temporal structure in reading times yield better prediction of text comprehension compared to reading speed. However, the results for fractal metrics are less clear. Furthermore, prediction of text comprehension is generally strongest and most consistent across silent and oral reading when comprehension scores are normalized by reading speed. Analyses of word length and word frequency indicate that the observed complexity in reading times is not a simple function of the lexical properties of the text, suggesting that text reading might work differently compared to reading of isolated word or sentences.

Reading fluency beyond decoding is a limitation to many children with developmental reading disorders. In the interest of remediating dysfluency, contributing factors need to be explored and understood in a developmental framework. The focus of this study is orthographic processing in developmental dyslexia, and how it may contribute to reading fluency. We investigated orthographic processing speed and accuracy by children identified with dyslexia that were enrolled in an intensive, fluency-based intervention using a timed visual search task as a tool to measure orthographic recognition. Results indicate both age and treatment effects, and delineate a link between rapid letter naming and efficient orthographic recognition. Orthographic efficiency was related to reading speed for passages, but not spelling performance. The role of orthographic learning in reading fluency and remediation is discussed.

Long-standing issues with the conceptualization, identification and subtyping of developmental dyslexia persist. This study takes an alternative approach to examine the heterogeneity of developmental dyslexia using taxometric classification techniques. These methods were used with a large sample of 671 children ages 6-8 who were diagnosed with severe reading disorders. Latent characteristics of the sample are assessed in regard to posited subtypes with phonological deficits and naming speed deficits, thus extending prior work by addressing whether these deficits embody separate classes of individuals. Findings support separate taxa of dyslexia with and without phonological deficits. Different latent structure for naming speed deficits was found depending on the definitional criterion used to define dyslexia. Non-phonologically based forms of dyslexia showed particular difficulty with naming speed and reading fluency.

Advances in neuroimaging techniques and analytic methods have led to a proliferation of studies investigating the impact of bilingualism on the cognitive and brain systems in humans. Lately, these findings have attracted much interest and debate in the field, leading to a number of recent commentaries and reviews. Here, we contribute to the ongoing discussion by compiling and interpreting the plethora of findings that relate to the structural, functional, and connective changes in the brain that ensue from bilingualism. In doing so, we integrate theoretical models and empirical findings from linguistics, cognitive/developmental psychology, and neuroscience to examine the following issues: (1) whether the language neural network is different for first (dominant) versus second (nondominant) language processing; (2) the effects of bilinguals' executive functioning on the structure and function of the “universal” language neural network; (3) the differential effects of bilingualism on phonological, lexical-semantic, and syntactic aspects of language processing on the brain; and (4) the effects of age of acquisition and proficiency of the user's second language in the bilingual brain, and how these have implications for future research in neurolinguistics.