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1.
The development of reading skills may depend to a certain extent on the development of basic visual perception. The magnocellular
theory of developmental dyslexia assumes that deficits in the magnocellular pathway, indicated by less sensitivity in perceiving
dynamic sensory stimuli, are responsible for a proportion of reading difficulties experienced by dyslexics. Using a task that
measures coherent motion detection threshold, this study examined the relationship between dynamic visual perception and reading
development in Chinese children. Experiment 1 compared the performance of 27 dyslexics and their age- and IQ-matched controls in the coherent motion detection task and
in a static pattern perception task. Results showed that only in the former task did the dyslexics have a significantly higher
threshold than the controls, suggesting that Chinese dyslexics, like some of their Western counterparts, may have deficits
in magnocellular pathway. Experiment 2 examined whether dynamic visual processing affects specific cognitive processes in reading. One hundred fifth-grade children
were tested on visual perception and reading-related tasks. Regression analyses found that the motion detection threshold
accounted for 11% and 12%, respectively, variance in the speed of orthographic similarity judgment and in the accuracy of
picture naming after IQ and vocabulary size were controlled. The static pattern detection threshold could not account for
any variance. It is concluded that reading development in Chinese depends to a certain extent on the development of dynamic
visual perception and its underlying neural pathway and that the impact of visual development can be specifically related
to orthographic processing in reading Chinese. 相似文献
2.
This study examines reading difficulty characteristics in Hebrew in three reading-impaired populations. Two are groups of dyslexics: 100 readers with impaired auditory perception and 100 readers with impaired visual perception. The third group comprises 61 readers with deep/severe hearing impairment. All were elementary schools students in the second to sixth grades. The subjects were tested with a conventional Hebrew reading test. It examined types of reading errors (e.g. changes of phonetic structure or word content), self-correction in reading, reading speed, sequential/holistic reading, the effect of reading texts with and without the Hebrew diacritical vowel signs ('punctuation'), and the effect of meaningful or meaningless text material on the amount of reading errors. The literature describes distinctions between various kinds of reading disability related to auditory impairment and visual perception, and the definition of dyslexia as being one category or including sub-groups. Our research hypothesis was that similar characteristics of reading difficulties would be found amongst auditory perception-impaired students and hearing-impaired students, and that they would differ from those of students with impaired visual perception. Our findings support this hypothesis. Many of the sub-tests revealed similarity in the reading difficulties between the hearing impaired students and those with impaired auditory perception versus the visually impaired. An unexpected finding revealed that fourth grade students in all the groups were a special sub-group in each group. These findings suggest, in accordance with a major research approach, that dyslexia should be defined in terms of dyslexia sub-groups rather than as a single category. 相似文献
3.
Rachel Schiff Miki Cohen Elisheva Ben-Artzi Ayelet Sasson Dorit Ravid 《Scientific Studies of Reading》2016,20(2):140-154
The aim of the present study is to examine the morphological knowledge of readers with developmental dyslexia compared to chronological age and reading-level matched controls. The study also analyzes the errors dyslexics make and their metamorphological awareness compared to controls. Participants included 31 seventh-grade dyslexic children and two matched control groups of normal readers: 34 seventh graders matched for chronological age and 32 third graders matched for reading age. Two tasks were administered via the auditory modality—morphological priming and morphological analogies task. We also performed error analysis and a metamorphological interview. Our analyses reveal that although dyslexics perform equally to chronological age matched controls on the priming task and similarly to reading-level matched controls on the morphological analogies task, their errors and metamorphological awareness are qualitatively different. 相似文献
4.
Nathlie A. Badian Gloria B. McAnulty Frank H. Duffy Heidelise Als 《Annals of dyslexia》1990,40(1):152-169
This study followed 163 boys from kindergarten through fourth grade. A battery of neurospychological and preacademic tests
and electrophysiological measures (BEAM) were administered in kindergarten, and reading tests at grade 4, in an attempt to
delineate precursors of dyslexia. Three of the kindergarten tasks (giving sounds associated with letters, rapid naming of
numbers, and finger localization) differentiated dyslexics from normal readers with 98 percent correct classification. The
tasks primarily involve grapheme-phoneme associations, storage and retrieval of phonological information in long-term memory,
and verbal labeling. Results are interpreted as confirming the role played by phonological processing tasks in the prediction
of dyslexia. Preliminary BEAM results for visual evoked potential topography suggest a significant increment in the distribution
of this potential in the left parietal and frontal region, and, for auditory evoked potential topography, a significant difference
between the two groups in the right posterior hemisphere.
This work was supported in part by NIHCD grants RO1HD18761 to F.H. Duffy, RO1HD18654 to H. Als, and the Mental Retardation
Grant P30HD18655 to C.F. Barlow. 相似文献
5.
The question of which cognitive impairments are primarily associated with dyslexia has been a source of continuous debate. This study examined the cognitive profile of Hebrew-speaking compensated adult dyslexics and investigated whether their cognitive abilities accounted for a unique variance in their reading performance. Sixty-nine young adults with and without dyslexia were administered a battery of tests measuring their reading skills and a number of cognitive abilities. The dyslexics were found to exhibit a generally poor cognitive profile, including their attention, visual working memory, naming, visual perception and speed of processing abilities, with the exception of high executive functions skills. Furthermore, naming speed, visual working memory and attention were significantly associated with decoding and fluency measures and predicted group difference after controlling for phonological skills. The findings point to the contribution of cognitive factors to decoding rate and possibly to the ability of utilizing rapid orthographic processes, thus effecting dyslexics’ reading performance. 相似文献
6.
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
7.
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
8.
Zvia Breznitz 《Reading and writing》2002,15(1-2):15-42
This study investigated whether asynchrony ofspeed of processing (SOP) betweenvisual-orthographic and auditory-phonologicalmodalities can account for word recognitiondeficits among dyslexic readers. SOP amongelementary school dyslexic readers was comparedto that of chronologically age-matched normalreaders. SOP was assessed using nonlinguisticand linguistic auditory and visual low-leveltasks and higher-level orthographic andphonological tasks. Behavioral andelectrophysiological (ERP) measures of SOP wereobtained. Data indicated that dyslexic readerswere significantly slower than control readersin most of the experimental tasks. Moreover,dyslexics revealed a systematic SOP gap betweenthe auditory-phonological and thevisual-orthographic modalities. This gap wasfound in both P200 and P300 latencies, andexplained most of the variance in wordrecognition. A theory is proposed suggestingthat asynchrony between the processing rates ofthe visual and the auditory modalities may bean underlying cause of dyslexia. 相似文献
9.
Is the dual route model of word recognition useful in explaining individual differences in reading behaviors for most developmental dyslexics? Many past case studies of surface and phonological acquired dyslexics and a few similar studies of developmental dyslexia have suggested this might be so. The present study investigated individual differences among a group of 65 dyslexics, age 10 to 13, in reading, phonemic segmentation, and word retrieval. The dyslexics’ performance was compared to that of 65 reading age controls and 17 age-matched good readers. The research questions were: (1) Are there discrete subgroups of developmental dyslexics as suggested by the case studies? (2) How do oral language measures relate to the various reading tasks? The data indicated there were no discrete subgroups within the group of dyslexics; in addition, the variability in performance on reading tasks was quite similar for the dyslexic and reading age-control groups. A few dyslexics resembled phonological dyslexics and surface dyslexics, but these subjects were still part of a continuum. We also report the relationship between phonemic segmentation and word retrieval and various reading tasks. It appears that dyslexics at extreme ends of the continuum may exhibit quite different patterns from each other in their oral language task performance as well as in their reading. 相似文献
10.
An unexpected and remarkable preference for second language reading among some dyslexics has been noted, presenting a challenge to accepted theory on dyslexia and the capacity for second language learning. The current study was designed to examine this phenomenon by systematically looking at the differential reading scores in the first and second languages of reading-disabled young Swedish adults who claimed to prefer reading in their second language (English). Three groups were selected for study: a group of 10 reading-disabled young adults who prefer to read English; a second group of 10 reading-disabled with no special preference for second language reading, matched on word recognition efficiency, age group, gender and educational level and a group of 10 normal readers matched on age group and educational level. The test battery was designed to compare overall reading efficiency in English and Swedish and therefore encompassed both speed and accuracy measures. The battery covered seven phonological measures, four orthographic measures,three isolated word reading measures, two continuous text reading measures, a comprehension task and an author recognition task. All tasks were carried out in both English and Swedish. The results showed that two dyslexic groups differed significantly in the degree to which task performance, including reading efficiency, was impeded by the English format. A tentative hypothesis was forwarded as to how the exceptional and unexpected facility with English might be explained. 相似文献
11.
P. G. Aaron 《Reading and writing》1989,1(4):291-308
This study tested the hypothesis that when a stringent criterion of normal IQ is applied in the selection of dyslexic readers, and when dyslexics, nondyslexic poor readers, and normal readers are matched on reading comprehension — rather than word reading — significant differences among these groups can be demonstrated. Two groups of poor readers from primary grades, one with normal IQ (dyslexics) and the other with below-average IQ (nonspecific reading disabled, NSRD) were matched for reading comprehension with a group of younger normal readers. The dyslexic group was found to be inferior to the other two groups in tests of decoding and spelling. The dyslexic readers were more context-dependent for word recognition than the other two groups. The NSRD group did not differ from the normal readers in these aspects but had the worst performance on a test of inferential comprehension. It was concluded that dyslexics differ from normal readers and low-IQ poor readers in word and nonword reading skills and context-dependency for reading. A group of six adult dyslexics were also found to be deficient in decoding skills. A lack of unanimity in the use of certain terminology, a substantial age difference between low-IQ poor readers and normals, and the difference in the criteria used for matching the different groups could be factors that can explain the disagreements seen between the findings of the present study and those reported by some other studies. Potential problems associated with reading-age matched experimental design are discussed. 相似文献
12.
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
13.
发展性阅读障碍儿童语篇阅读中的笔画数效应 总被引：1，自引：1，他引：0
采用识字量测试、拼音测试、阅读理解测试、正字法测试、快速命名测试五项测试任务从小学五年级120名学生和小学三年级132名学生中筛选出五年级11名阅读障碍生和三年级12名能力匹配生,利用眼动技术对汉语阅读障碍儿童语篇阅读过程的眼动特征及其视觉认知加工特点进行了初步探索。结果表明：两组被试在平均注视时间、平均眼跳幅度和总注视时间三项指标上均没有显著差异,在目标词的眼动指标上也差异不显著。两组被试均发现显著的笔画数效应。以上结果支持了发展性阅读障碍只是一般的发展落后的观点。 相似文献
14.
Franklin R. Manis Mark S. Seidenberg Lynne Stallings Marc Joanisse Caroline Bailey Laurie Freedman Suzanne Curtin Patricia Keating 《Annals of dyslexia》1999,49(1):105-134
There is a consensus that dyslexia is on a continuum with normal reading skill and that dyslexics fall at the low end of the
normal range in phonological skills. However, there is still substantial variability in phonological skill among dyslexic
children. Recent studies have focused on the high end of the continuum of phonological skills in dyslexics, identifying a
“surface” dyslexic, or “delayed” profile in which phonological skills are not out of line with other aspects of word recognition.
The present study extended this work to a longitudinal context, and explored differences among subgroups of dyslexics on a
battery of component reading skills. Third grade dyslexics (n=72) were classified into two subgroups, phonological dyslexics and delayed dyslexics, based on comparisons to younger normal
readers at the same reading level (RL group). The children were tested at two points (in third and fourth grade). The results
revealed that the classification of dyslexics produced reliable, stable, and valid groups. About 82 percent of the children
remained in the same subgroup category when retested a year later. Phonological dyslexics were lower in phoneme awareness
and expressive language. Delayed dyslexics tended to be slower at processing printed letters and words but not at rapid automatic
naming of letters, and relied more heavily on phonological recoding in reading for meaning than did phonological dyslexics.
A subset of the delayed dyslexics with the traditional “surface dyslexic” pattern (relatively high pseudoword and low exception
word reading) was also identified. The surface subgroup resembled the RL group on most measures and was not very stable over
one year. The results are discussed in light of current models of dyslexia and recent subgrouping schemes, including the Double-Deficit
Hypothesis. 相似文献
15.
This study evaluated the effect of sound-symbol association training on visual and phonological memory in children with a history of dyslexia. Pretests of phonological and visual memory, a sound-symbol training procedure, and phonological and visual memory posttests were administered to children with dyslexia, to children whose dyslexia had been compensated through remedial training, and to age- and reading level-matched comparison groups. Deficits in visual and phonological memory and memory for sound-symbol associations were demonstrated in the dyslexia group. For children with dyslexia and children whose dyslexia had been remediated, the sound-symbol training scores were significantly associated with word and pseudoword reading scores and were significantly lower than those of the comparison groups. Children with dyslexia and children whose dyslexia had been compensated showed significantly less facilitation of phonological memory following the training than did typical readers. Skilled readers showed some reduction in accuracy of visual memory following the training, which may be the result of interference of verbalization with a predominantly visual task. A parallel decrease was not observed in the children with dyslexia, possibly because these children did not use the verbal cues. Children with dyslexia and children whose dyslexia had been compensated seemed to have difficulty encoding the novel sounds in memory. As a result, they derived less phonological memory advantage and less visual memory interference from the training than did typical readers. Children in the compensated dyslexia group scored lower on sound-symbol training than their age peers. In other respects, the scores of these children were equivalent to those of the typically reading comparison groups. Children in the compensated dyslexia group exhibited higher phonological rehearsal, iconic memory, and associative memory scores than children in the dyslexia group. Implications for the remediation of dyslexia are discussed. 相似文献
16.
The reading levels and reading strategies of 43 children with genetic dyslexia, right-hemisphere lesions/dysfunction, and
left-hemisphere lesions/dysfunction were retrospectively compared. Age and IQ were comparable. Only children who had a verbal
or performance IQ over 90 were included in the study. Although the genetic dyslexics had a significantly higher Full Scale
IQ than the other two groups, their reading level was significantly lower. This suggests that a disturbance of the normal
processes of neuronal migration during fetal development may have profound effects on specific cognitive processes, without
affecting others. In contrast, 50 percent of the boys with left-hemisphere deficits were disabled readers. One-third of the
boys with right-hemisphere deficits were also poor readers. With one exception, the girls, who had comparable deficits, were
good readers. A comparison was made between the groups in terms of reading strategies and patterns of errors. 相似文献
17.
Hsiao-Lan Sharon Wang Martina Huss Jarmo A. H?m?l?inen Usha Goswami 《Reading and writing》2012,25(2):509-536
The present study explores the relationship between basic auditory processing of sound rise time, frequency, duration and
intensity, phonological skills (onset-rime and tone awareness, sound blending, RAN, and phonological memory) and reading disability
in Chinese. A series of psychometric, literacy, phonological, auditory, and character processing tasks were given to 73 native
speakers of Mandarin with an average age of 9.7 years. Twenty-six children had developmental dyslexia, 29 were chronological
age-matched controls (CA controls) and 18 were reading-matched controls (RL controls). Chinese children with dyslexia were
significantly poorer than CA controls in almost all phonological tasks, in semantic radical search, and in phonological recoding
proficiency. Chinese children with dyslexia also showed significant impairments in most of the basic auditory processing tasks.
Regression analyses demonstrated that different auditory measures of rise time discrimination were the strongest predictors
of individual differences in Chinese character reading (1 Rise task) and phonological recoding (2 Rise task) respectively,
with frequency discrimination also important for nonsense syllable decoding. Our results support the hypothesis that accurate
perception of the amplitude envelope of speech is critical for phonological development and consequently reading acquisition
across languages. 相似文献
18.
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
19.
Insufficient knowledge of the subtle relations between words’ spellings and their phonology is widely held to be the primary limitation in developmental dyslexia. In the present study the influence of phonology on a semantic-based reading task was compared for groups of readers with and without dyslexia. As many studies have shown, skilled readers make phonology-based false-positive errors to homophones and pseudohomophones in the semantic categorization task. The basic finding was extended to children, teens, and adults with dyslexia from familial and clinically-referred samples. Dyslexics showed the same overall pattern of phonology errors and the results were consistent across dyslexia samples, across age groups, and across experimental conditions using word and nonword homophone foils. The dyslexic groups differed from chronological-age matched controls by having elevated false-positive homophone error rates overall, and weaker effects of baseword frequency. Children with dyslexia also made more false-positive errors to spelling control foils. These findings suggest that individuals with dyslexia make use of phonology when making semantic decisions both to word homophone and non-word pseudohomophone foils and that dyslexics lack adequate knowledge of actual word spellings, compared to chronological-age and reading-level matched control participants. 相似文献
20.
The visual deficit hypothesis of development dyslexia has largely been abandoned because many of the phenomena that initially motivated it could not be replicated under controlled experimental conditions, while phonological processing deficits were found to provide a better explanation for the replicable phenomena. Nevertheless, many teachers and special educators continue to subscribe to the hypothesis that deficits of visual perception are a major cause of reading failure in dyslexia. As part of a larger family study, we reexamined the questions (1) whether probands and affected relatives in dyslexia families reverse easily confused letters more frequently under experimental conditions than normal readers from the same families, and (2) whether they show unusual facility in reading geometrically transformed text. The findings indicated that young dyslexia students reverse easily confused letters more often than normal readers. Reading group differences of letter reversal were significant in children from 7–10 years but not thereafter; and virtually no subject reversed letters when spelling whole words. Furthermore, dyslexic persons in every age group from 7–60 years actually took longer than normal readers to decode geometrically transformed text; and the time to decode transformed texts increased progressively with age after adolescence in both dyslexic persons and normal readers. Thus, reading group differences in decoding easily confused letters and reading geometrically transformed text do not support the visual deficit hypothesis and probably do not help to clarify the etiology of developmental dyslexia. 相似文献