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1.
Shay Menashe 《Annals of dyslexia》2018,68(2):145-164
The aim of this study was to gain additional knowledge about the asynchrony phenomenon in developmental dyslexia, especially when spatial selective attention is manipulated. Adults with developmental dyslexia and non-impaired readers underwent two experimental tasks, one including alphabetic stimuli (pre-lexical consonant–vowel syllables) and the other containing non-alphabetic stimuli (pictures and sounds of animals). Participants were instructed to attend to the right or left hemifields and to respond to all stimuli on that hemifield. Behavioral parameters and event-related potentials were recorded. The main finding was that the dyslexic readers demonstrated asynchrony between the auditory and visual modalities when alphabetic stimuli were presented on the right hemifield. These results suggest that intact reading is linked to a synchronized auditory and visual speed of processing even when spatial selective attention is manipulated. The findings of the current study are discussed in terms of asynchrony between modalities as a neurocognitive marker in developmental dyslexia. 相似文献
2.
The simultaneous auditory processing skills of 17 dyslexic children and 17 skilled readers were measured using a dichotic listening task. Results showed that the dyslexic children exhibited difficulties reporting syllabic material when presented simultaneously. As a measure of simultaneous visual processing, visual attention span skills were assessed in the dyslexic children. We presented the dyslexic children with a phonological short-term memory task and a phonemic awareness task to quantify their phonological skills. Visual attention spans correlated positively with individual scores obtained on the dichotic listening task while phonological skills did not correlate with either dichotic scores or visual attention span measures. Moreover, all the dyslexic children with a dichotic listening deficit showed a simultaneous visual processing deficit, and a substantial number of dyslexic children exhibited phonological processing deficits whether or not they exhibited low dichotic listening scores. These findings suggest that processing simultaneous auditory stimuli may be impaired in dyslexic children regardless of phonological processing difficulties and be linked to similar problems in the visual modality. 相似文献
3.
《Scientific Studies of Reading》2013,17(1):17-42
This research was aimed at contributing to the current understanding of the underlying factors of naming speed and the causes of naming speed deficits. Forty regular readers and 40 dyslexic university students participated in the study. Electrophysiological (Event-Related Potentials [ERPs]) and behavioral measures were employed. Behavioral baseline tasks assessed general ability, reading skills, reading-related cognitive abilities, and standard Rapid Automatized Naming (RAN) and Rapid Alternating Stimulus tests. ERP tasks included letter and object naming tasks adapted for electrophysiological research presentation. The dyslexics were significantly slower and less accurate than the controls on most of the baseline measures. On all the naming tasks, the peak ERP latencies were elicited later, reaction times were longer, and the P300 latency width was wider among the dyslexics as compared to the regular readers. On the choice reaction time naming tasks, accuracy for both groups was almost perfect. When naming presentation time was controlled by the experiment, the dyslexics were significantly less accurate than the controls. Our data indicated that effective naming speed was related to an earlier P200 latency peak among regular readers and to an earlier P300 latency peak and narrower area component activation in the dyslexic group. The results from this study suggest that effective RAN speed among regular readers might be a result of efficient processing of RAN information at the input stage of stimulis perception and evaluation as well as of updating and processing the information in short-term memory among dyslexics. 相似文献
4.
通过对比优、劣汉语阅读者在视觉、听觉时间加工任务中的表现,探讨不同水平的正常阅读者中存在的时间加工能力差异。选择阅读能力正常的小学三年级学生,筛选优秀阅读者18人,拙劣阅读者16人,施以瑞文智力测试及一系列阅读能力测试。采用时间顺序判断的经典范式,分别考察了两组被试的视觉、听觉时间加工能力。数据分析结果表明:优秀汉语阅读者的视、听觉时间加工能力,均显著地高于拙劣汉语阅读者,但当智力因素被控制后,组间差异的显著性消失。 相似文献
5.
It has been suggested that the differences observed for dyslexic readers compared to normal readers on tasks measuring visual sensitivity may simply be the result of differences between the two groups in general cognitive ability and/or attentional engagement. One common way to accommodate this proposal is to match normal and dyslexic readers on IQ. However, an explicit test of this suggestion is to take normal and dyslexic readers who differ on IQ—where IQ would be expected to explain reading ability—and determine if visual sensitivity can still account for reading skill, even when IQ is taken into account. In this study we explored the relative contributions of nonverbal IQ, visual sensitivity as measured by sensitivity to the frequency doubling illusion, and phonological and irregular word reading to reading ability. Visual sensitivity explained a significant amount of variance in reading ability, over and above nonverbal IQ, accounting for 6% of the unique variance in reading ability. Moreover, visual sensitivity was related primarily to irregular word reading rather than to nonsense word decoding. This study demonstrates that low-level visual sensitivity plays an intrinsic role in reading aptitude, even when IQ differences between normal and dyslexic readers are contrived to maximize the contribution of IQ to reading skill. These results challenge the suggestion that impaired visual sensitivity may be epiphenomenal to poor reading skills. 相似文献
6.
Nathlie A. Badian 《Reading and writing》1994,6(1):45-63
The rationale for the study was that if dyslexic and garden-variety poor readers differ in reading-related cognitive skills, there is justification for believing dyslexia to be a distinct entity. Subjects were 110 children aged 6 to 10 years, divided into groups of dyslexic poor readers varying in verbal IQ, garden-variety poor readers, and good readers. Findings suggest that there are valid grounds for believing that dyslexia is a separate entity from garden-variety poor reading, and that it is found among children at all verbal IQ levels. Poor phonological awareness and nonword reading, in relation to normal readers, were shared by dyslexic and garden-variety poor readers. Deficits unique to dyslexic poor readers were problems in both automatic visual recognition and phonological recoding of graphic stimuli. The study supports the phonological-core variable-difference model of Stanovich (1988) in that both dyslexic and garden-variety poor readers showed phonological processing deficits, but they were more extensive in dyslexics. 相似文献
7.
In addition to an intrinsic difficulty in reading and spelling, one of the defining characteristics of dyslexia is an enduring and pervasive difficulty in phonological coding, such that dyslexic readers find it particularly challenging to process and manipulate the constituent sounds of a language. Coexistent with this finding is the evidence that some dyslexic readers also demonstrate subtle sensory coding problems in the visual and auditory domains. Few theories have been proposed to unite these different findings within a coherent model of reading. Here the evidence for visual, auditory and phonological coding problems in dyslexia is briefly reviewed, and a hypothesis is proposed for how adequate early sensory coding may be intrinsic to phonological awareness and subsequent reading ability. In this hypothesis, a cortical network is assumed that incorporates the visual, auditory and phonological skills of reading. The visual sub‐component of the network is mediated by the dorsal visual pathway, which is responsible for the accurate spatial encoding of letters, words and text. The auditory component of the network in pre‐readers is intrinsic to the development of phonological sensitivity, and then grapheme‐phoneme assimilation as reading skills develop. In this hypothesis, some of the symptoms of dyslexia may result from subtle problems in the encoding of both visual and auditory information and their role in maintaining the synchronicity of the reading network. 相似文献
8.
Franklin R. Manis Patricia A. Szeszulski Liana K. Holt Kathryn Graves 《Annals of dyslexia》1988,38(1):139-153
In this paper we apply a developmental model of reading to the question of dyslexic subtypes. Groups of normal readers (n=40)
and dyslexic children (n=50), matched on reading level and IQ, were given a comprehensive test battery measuring level of
development of visual, phonological, and orthographic skills. As a group, dyslexics deviated from normal readers of equivalent
reading achievement primarily in phonological skills (spelling-to-sound translation and phonemic analysis), although limited
differences in knowledge of word-specific spellings were also observed. Dyslexics were superior to the younger normal readers
in visual processing of print. Analysis of individual data by reference to the reading level control group revealed three
major subgroups: a group with a specific deficit in phonological processing of print (52 percent), a group with deficits in
processing both the phonological and orthographic features of printed words (24 percent), and a group with phonological deficits
in language (8 percent). The remainder of the sample (16 percent) had specific deficits in visual or orthographic processing
of print, in spelling, or did not differ from the control group. The data support the view that most developmental dyslexics
have a specific language disorder involving some aspect of phonological processing. However, small subgroups with very different
configurations of reading and nonreading difficulties may exist as well.
This research was supported by an NICHD grant to the first author (USPHS grant 1 R23 HD20231). 相似文献
9.
Shelley Shaul 《Reading and writing》2012,25(5):1143-1170
This study examined the differences in processing between regular and dyslexic readers in a lexical decision task in different
visual field presentations (left, right, and center). The research utilized behavioral measures that provide information on
accuracy and reaction time and electro-physiological measures that permit the examination of brain activity during cognitive
processing. Two groups of university students, regular and dyslexic readers, were matched on age, gender, intelligence, socioeconomic
status, and handedness. A lexical decision task was used in order to examine the processes during word recognition. Subjects
were required to decide whether a sequence of letters constituted a real word existing in spoken language or whether the stimulus
seen was not an accurate word. For the behavioral measures, it was found that the dyslexics read slower and with more errors
than the regular readers. Moreover, the ERP components appeared later in dyslexics as compared to regular readers in this
task. The performance of the dyslexics improved and even approached that of the regular readers when the stimuli were presented
to the left visual field. Thus, it seems that the dyslexics were relying more on their right hemisphere for linguistic processing,
whereas the regular readers were relying more on their language areas in the left hemisphere. 相似文献
10.
This paper reports a research which examined the relationship between dyslexia and eye movement control in Spanish speaking children. The study compared the eye movements recordings of 30 dyslexic, 30 retarded and 30 normal readers, aged between 7 and 14, in one ocular tracking task and two reading tasks which differed in their degree of reading difficulty. Within each group the subjects were divided into 3 subgroups of 10 in accordance with the following chronological ages: 7–9, 10–11 and 12 years and above. Dependent variables were saccadics (number, size and fixation pause), regressives (number, size and fixation pause), total number of movements and percentage of regressives over the total number of movements. The following results were obtained: (1) In the two reading tasks significant differences were found between dyslexic and normal readers and between retarded and normal readers in most of the parameters, no differences being found between dyslexic and retarded readers except in a few parameters; (2) in the ocular tracking task significant differences both between dyslexic and normal readers and between dyslexic and retarded readers were found in all dependent variables, no differences being found between retarded and normal readers at all, and (3) the age factor produced a significant main effect in the two reading tasks indicating a general improvement of eye movements as age increases but an interaction effect with reading disability in the ocular tracking task-indicating a deterioration in eye movements in the dyslexic group as a function of age-was also found. The results are discussed in the context of alternative theoretical explanations of developmental dyslexia.This research was supported by grant PR82-1933 from the Spanish Consulting Committee for Scientific and Technological Research (CAYCIT). Requests for reprint should be sent to F. J. Martos, Departamento de Psicologia Experimental y Fisiologia del Comportamiento. Campus de Cartuja, Universidad de Granada. 18071 Granada, Spain. 相似文献
11.
The purpose of this study was to investigate whether among children who speak Kannada, a Dravidian language from South India, there are those who show the same pattern of specific dyslexia as has been found to occur in children who speak European languages. The performances of 14 dyslexic children, aged between 8 and 10 years, whose native language was Kannada, were compared on a variety of tasks with fourteen normal readers and fourteen non-dyslexic poor readers. There were no significant differences between the three groups on tests of visual discrimination, visual recognition, visual recall, memory for shapes in sequence, or auditory discrimination. There were differences, however, between the dyslexics and the normal readers on tests of recall of auditorily presented digits, word analysis, word synthesis, and on two tests of visual-verbal association. The non-dyslexic poor readers were more similar to the dyslexics on recall of auditorily presented digits and word synthesis but more similar to the normal readers on word analysis and on the two tests of visual-verbal association. It is argued that these results are evidence of a consistent pattern in specific dyslexia which does not depend on any one writing system or geographical location. 相似文献
12.
The background noise of response times is often overlooked in scientific inquiries of cognitive performances. However, it is becoming widely acknowledged in psychology, medicine, physiology, physics, and beyond that temporal patterns of variability constitute a rich source of information. Here, we introduce two complexity measures (1/f scaling and recurrence quantification analysis) that employ background noise as metrics of reading fluency. These measures gauge the extent of interdependence across, rather than within, cognitive components. In this study, we investigated dyslexic and non-dyslexic word-naming performance in beginning readers and observed that these complexity metrics differentiate reliably between dyslexic and average response times and correlate strongly with the severity of the reading impairment. The direction of change in the introduced metrics suggests that developmental dyslexia resides from dynamical instabilities in the coordination among the many components necessary to read, which could explain why dyslexic readers score below average on so many distinct tasks and modalities. 相似文献
13.
14.
This paper investigates the relationship between phonological processing and reading ability amongst grade 4 and grade 5 Arabic
speaking children in Egypt. In addition to measuring reading level, the study assessed the children’s ability to identify
rhymes, delete individual phonemes from words, retain and manipulate sequences of digit names and rapidly access verbal labels.
Further literacy and literacy-related tasks required children to decode novel letter strings, to distinguish similar words,
to identify words within letter chains and to correctly spell dictated text. A non-verbal ability measure was also included
to allow comparisons to be made between a group of poor readers with good non-verbal skills (dyslexics) with a control group
of chronological-age-matched normal readers with equivalent average scores on the non-verbal task. Results indicated relationships
between literacy ability, decoding and phonological processing within this cohort, as well as identifying differences between
dyslexic and control groups that suggest Arabic dyslexics show signs of poor phonological skills. The study supports the view
that Arabic dyslexic children have impairments in the phonological processing domain. 相似文献
15.
The present study was designed to investigate the influence of syntactic complexity on sentence comprehension in Hebrew. Participants were 40 native Hebrew-speaking 5th grade dyslexic and normally reading children aged 10–11 years. Childrens syntactic abilities were tested by three experimental measures: syntactic judgment, a sentence-picture matching task, and a sentence correction task. Each task consisted of sentences composed of five syntactic constructions varying in the level of syntactic complexity (active, passive, conjoined, object-subject relative, and subject-object relative). The length of sentences and the number of propositions in the sentences were controlled. In addition, a wide range of the childrens reading and general abilities (e.g., reading comprehension, phonological awareness, and working memory) was examined. The results indicated that dyslexic readers were less accurate and slower than good readers in all reading tasks and in the tasks on sentence comprehension. The findings suggest that the factor of syntactic complexity seems to be a relatively independent aspect of sentence comprehension. This aspect of sentence comprehension is probably not affected in dyslexic readers. Rather, processing deficit related to phonological and memory impairments of dyslexic children and their ability to process syntactic information is responsible for the difficulties in sentence comprehension. 相似文献
16.
17.
Kevin K. H. Chung Jason C. M. Lo Connie S.-H. Ho Xiaoyun Xiao David W. Chan 《Annals of dyslexia》2014,64(3):222-247
This study aims to investigate the relation of syntactic and discourse skills to morphological skills, rapid naming, and working memory in Chinese adolescent readers with dyslexia and to examine their cognitive–linguistic profiles. Fifty-two dyslexic readers (mean age, 13;42) from grade 7 to 9 in Hong Kong high schools were compared with 52 typically developing readers of the same chronological age (mean age, 13;30) in the measures of word reading, 1-min word reading, reading comprehension, morpheme discrimination, morpheme production, morphosyntactic knowledge, sentence order knowledge, digit rapid naming, letter rapid naming, backward digit span, and non-word repetition. Results showed that dyslexic readers performed significantly worse than their peers on all the cognitive-linguistic tasks. Analyses of individual performance also revealed that over half of the dyslexic readers exhibited deficits in syntactic and discourse skills. Moreover, syntactic skills, morphological skills, and rapid naming best distinguished dyslexic from non-dyslexic readers. Findings underscore the significance of syntactic and discourse skills for understanding reading impairment in Chinese adolescent readers. 相似文献
18.
Given the well-acknowledged phonological deficit found in dyslexic children, this study was aimed at investigating graphophonological processes in dyslexic readers of French over a 1-year period. Among the different types of phonological processing can be distinguished those related to phonological awareness based on knowledge of the oral language and graphophonological processes based on correspondences between the oral and the written language. In this study, we evaluated graphophonemic and graphosyllabic processes using, in each case, two different tasks varying in the degree of cognitive constraint associated with the task (CC- vs CC+). Twenty 11 year-old dyslexic students were compared with younger normal-readers of the same reading level (RA, n=26) and to normal-readers of the same age (CA, n=24). Two variables were considered in the analyses: accuracy and response latency. Results show that dyslexic readers do process written items at the graphophonological level. Also, results indicate main effects of task (CC- vs CC+), time (T1 vs T2), and group (DYS vs RA vs CA). In general, dyslexic participants' performances are comparable to those of RA and differ from those of CA. 相似文献
19.
The present study investigates the performance of persons with reading disabilities (PRD) on a variety of sequential visual-comparison tasks that have different working-memory requirements. In addition, mediating relationships between the sequential comparison process and attention and memory skills were looked for. Our findings suggest that PRD perform worse than normally achieving readers (NAR) when the task requires more than a minimal amount of working memory, unrelated to presentation rate. We also demonstrate high correlations between performance on the task with the most working-memory demands and reading-related skills, suggesting that poor working-memory abilities may be one of the underlying mechanisms of dyslexia. The mediating model analysis indicates that order judgment tasks are mediating to verbal working memory, suggesting that visual sequence memory precedes auditory sequence memory. We further suggest that visual tasks involving sequential comparisons could probe for poor working memory in PRD. 相似文献
20.
Good and poor readers at the junior high school level and good and poor spellers at the university level were compared on their ability to produce words in response to a semantic cue (a category name), a visual cue (three letters), and an auditory cue (a syllable rime). Kindergarten children were tested on a word-identification task and their retrieval of words in response to the semantic and auditory cues. At all ages, poor readers or spellers produced fewer words on all word-retrieval tasks than did good readers or spellers. Performance on the auditory and visual word-retrieval tasks correlated very highly with pseudoword reading and spelling ability in the two older groups; in the kindergarten children, auditory retrieval correlated with word identification. The results suggest that poor readers have not organized words in long-term memory according to rhyming families but that good readers have. We speculate that failure to retrieve rhyming words during acquisition of reading and spelling skills underlies the failure of poor readers and spellers to abstract the higher-order relationships between orthography and phonology. 相似文献