首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 781 毫秒
1.
Hypothesized cognitive strengths and weaknesses of three dyslexic subgroups (Boder and Jarrico 1982) were examined in two reading related experiments. The first experiment tested the prediction that auditorily presented letter sets should be processed better by dyseidetic than by dysphonetic readers. The prediction was not confirmed. The results did not show any modality of presentation-specific recall differences between the three dyslexic subgroups. Overall, dyslexic children’s scores were significantly lower than those of age-matched control groups. The second experiment tested predictions of differential performance of dyseidetic and dysphonetic readers in a task in which the name identity of letters in pairs had to be indicated. Predicted patterns were not confirmed. Compared to the control groups all three dyslexic subgroups (whose means did not differ significantly) made significantly more errors in the condition in which it was essential to activate phonetic representations of the letters. The experimental results of this study suggest a greater similarity in the nature of letter processing problems in dyslexic children than is assumed in Boder and Jarrico’s (1982) subtyping test. This research was supported by grant 634301 from the Department of Special Education, State University of Groningen, and a travel grant from the Netherlands Organization for the Advancement of Pure Research (Z.W.O.). Based on a presentation at the 32nd Annual Conference of The Orton Dyslexia Society, Baltimore, Maryland, November 1982.  相似文献   

2.
Three studies were conducted in order to determine if reading disability subtypes identified by Mattis, Boder, and Doehring were present in neurologically-impaired students with and without reading disabilities. The anomic-language disorder subtype, dysphonetic and mixed dysphonetic-dyseidetic subtypes, and Doehring’s three subtypes were all present, primarily in the reading-disabled sample. Subtypes related to visual-spatial impairment were equally or more apparent in the non-reading-disabled sample. It is concluded that the visual-perceptual disorder subtypes may reflect neurological impairment but be unrelated to reading disability. It remains tenable to hypothesize that the other subtypes found may reflect the ways in which neurological impairment interferes with reading and that subtle neurological impairment may be present in dyslexic students who fall into the same subtypes.  相似文献   

3.
Spatial and temporal matching abilities of 67 male and female fifth and sixth grade average (18) and severely disabled readers (49) were investigated. Subjects were classified according to the Boder Diagnostic Screening Procedure readers: dysphonetic, dyseidetic, and alexic. Results of the matching task indicated that average and dyseidetic readers were better able than dysphonetic and alexic readers to match purely temporal information. When order of difficulty among the spatial and temporal tasks was analyzed, dysphonetic and alexic readers demonstrated greater difficulty with temporal information. Matching abilities were found to be less related to integration ability than to an ability to sequence temporal information. The existence of possible memory and neurological correlates is discussed.  相似文献   

4.
Electrophysiological correlates of dyslexic subtypes.   总被引:1,自引:0,他引:1  
The construct validity of Boder's typology of dyslexia was investigated using quantified EEG. Thirty-nine children, ranging in age from 7-0 to 10-11, were recorded during a contextual reading task and at rest. During reading, children with dyslexia were expected to show increased theta and beta amplitude compared to nondisabled readers. These differences were expected in regions of presumed strength for each subtype as a sign of overengagement in task. Children with phonological deficits (dysphonetic dyslexia) were expected to adopt visuospatial processing strategies (right occipital-parietal activation), those with orthographic deficits (dyseidetic dyslexia) to emphasize phonetic strategies (left temporal-parietal activation). Results supported beta frequency differences in anticipated regions by subtype during the reading task. However, the direction of difference hypothesis was not supported. Decreased amplitudes in both groups with dyslexia compared to normally achieving readers suggest reconceptualization of the theoretical base for the Boder subtyping system.  相似文献   

5.
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   

6.
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.
Recent studies have suggested that an increase of inter-letter spacing may improve reading performance of dyslexic readers by reducing visual crowding. However, these results have been difficult to replicate.This study directly compares reading accuracy and comprehension, as well as reading speed, and number and duration of fixations of 38 dyslexic and 32 typically reading children (10–14 years old) in regular, spaced (+2,5 pt), and condensed (−1,5 pt) conditions using a natural sentence-reading paradigm.Inter-letter spacing did not affect reading accuracy, comprehension, or speed. The lack of effects of inter-letter spacing was observed in both dyslexic and typical readers. Inter-letter spacing did not impact the number of fixations, but increased inter-letter spacing led to shorter fixations in dyslexic children. Decreased inter-letter spacing resulted in longer fixations in both groups.These results do not support the claim that dyslexics are more influenced by crowding than age-matched controls.  相似文献   

8.
Conclusions Evidence of different syndromes of developmental dyslexia raises the question of the interaction between dyslexic types and patterns of cerebral dominance. Some of the proposed classifications of dyslexia, and most notably the one proposed by Boder (1971), strongly suggest that dyslexic subtypes, that can be identified clinically by reading-spelling patterns, may possess different or opposite cerebral dominance patterns. Thus, research of cerebral dominance in dyslexia (i.e., Orton’s hypothesis) should involve careful selection and classification of subjects. When this is done it can be shown that electrophysiological measures can identify cerebral-dominance abnormalities in at least one subtype of developmental dyslexia. This paper was presented in part at the 29th Annual Conference of The Orton Society, November 1978, in Minneapolis, Minnesota.  相似文献   

9.
The study evaluated a substantially updated version of Orton's (1937) classical idea of a significant relatonship in dyslexic children between cerebral lateralization and their word decoding deficits. Attentional lateralization was examined under the assumption that covert spatial attention when directed contralaterally interacts with ageinvariant cerebral asymmetries for receptive speech. Thirty dysphonetic dyslexic children were compared to 30 younger normal readers who were matched to the dyslexics in reading comprehension. The children were tested in left ear (LE) and right ear (RE) directed attention dichotic listening (DAD), and in pseudoword decoding, word recognition, reading comprehension, spelling, arithmetic, and in general intelligence (IQ). Group comparisons in DAD failed to show any differences, confirming the mounting evidence that dyslexia is not related to incomplete lateralization. Entering the DAD scores of the dyslexics (LE first, LE second, RE first, RE second) as predictors of achievement revealed that, independently of chronological age (CA) and IQ, their ability to recall items from the LE first produced a negative regression which predicted 42 percent of the variance in pseudoword decoding. Selective report from the LE also produced small but significant negative correlations with visual recognition of real words and spelling; but no relationship to reading comprehension. IQ was related to reading comprehension and to the ability to shift attention from the LE to the RE. Eventhough the dyslexics were lateralized normally, weak lateralization was related specifically to phonological word decoding, a core deficit in dyslexia. However, unlike Orton's concept, these findings suggest that dyslexics suffer from exuberant right hemisphere processing in response to spatial attentional demands that, in turn, interferes transcallosally with the development of the sound-symbol representations that are required for fluent reading. Lateralization, per se, is unaffected by the disorder.  相似文献   

10.
This paper reports two experiments which focus on the object naming deficits of dyslexic readers. In Experiment 1, dyslexic and normal readers were asked to name objects depicted by pictures or following their spoken definition. Ten-year-old dyslexics named fewer objects correctly than other children of a similar age, performing only as well as a younger group of 8-year-old normal readers. This was true irrespective of the modality through which they were tested. In terms of naming latency, however, they were similar to comparison groups. In Experiment 2, nine-year-old dyslexic and normal readers performed as well as each other in a receptive vocabulary test in which pictures had to be matched to spoken words. However, once again, on a picture naming test, the dyslexics did less well than controls. We argue that dyslexic children are subject to verbal naming difficulties which cannot be accounted for by generally low levels of vocabulary knowledge. Their problems are attributable not to difficulties in semantic representation but to difficulties with the lexical-phonological representation of spoken words they know. We propose that, in turn, these difficulties are related to their memory and reading problems.  相似文献   

11.
The purpose of this study was to test the developmental lag hypothesis, which assumes that a surface pattern of reading difficulties should be attributed to a general developmental delay rather than to specific deficits in the acquisition of orthographic decoding skills. We compared a sample of very low birth weight children (less than 1,500 g), known to be at higher risk of a general developmental delay, with a group of same-age, normal readers. Following the same regression-based procedures seen in the work of Castles and Coltheart (1993); Manis, Seidenberg, Doi, McBride-Chang, and Petersen (1996); and Stanovich, Siegel, and Gottardo (1997), we found that only 1 very low birth weight child could be classified as phonologically dyslexic, whereas 12 out of 60 very low birth weight children were identified as surface dyslexic. This subgroup of children with surface dyslexia was impaired not only in all reading measures employed in this study, but also in several behavioral domains associated with a developmental lag.  相似文献   

12.
In an opaque orthography like English, phonological coding errors are a prominent feature of dyslexia. In a transparent orthography like Spanish, reading difficulties are characterized by slower reading speed rather than reduced accuracy. In previous research, the reading speed deficit was revealed by asking children to read lists of words. However, speed in list reading sums the time required to prepare an utterance, reaction time (RT), with the time required to say it, response duration (RD). Thus, the dyslexic speed deficit in transparent orthographies could be driven by slow RTs, by slow RDs, or both. The distinction is especially important if developmental readers rely on phonological coding to achieve lexical access because the whole word would have to be encoded before it could be identified. However, while the factors that affect reading RT have been extensively investigated, no attention has been paid to RD. We studied the performance of typically developing and dyslexic Spanish children in an oral reading task. We analysed the impact of word frequency and length on reading accuracy, RT, and RD. We found that accuracy, RT, and RD were affected by word frequency and length for both control and dyslexic readers. We also observed interactions between effects of reader group—dyslexic, typically developing (TD) younger or TD older readers—and effects of lexicality, frequency, and word length. Our results show that children are capable of reading aloud using lexical and sub-lexical coding processes in a transparent orthography.  相似文献   

13.
Dyslexia and the double deficit hypothesis   总被引:1,自引:4,他引:1  
The double deficit hypothesis (Bowers and Wolf 1993) maintains that children with both phonological and naming-speed deficits will be poorer readers than children with just one or neither of these deficits. In the present study, we drew on this hypothesis to help understand why some children have a serious reading impairment. In addition, by adding an orthographic factor, we extended it to a triple deficit hypothesis. Participants were 90 children aged 6 to 10 years. Dyslexic children, whose reading was low for age and for expected level, garden-variety poor readers, reading-level matched younger children, and low verbal IQ good readers, were compared. The dyslexic group was significantly lower then the garden-variety poor readers and the low verbal IQ good readers on most measures, and lower than the younger group on phonological measures. Findings support the double deficit hypothesis of Bowers and Wolf, and also the triple deficit hypothesis. Most of the poorest readers, nearly all of whom qualified as dyslexic, had a double or triple deficit in phonological, naming-speed, and orthographic skills. Conclusions were that dyslexia results from an overload of deficits in skills related to reading, for which the child cannot easily compensate.  相似文献   

14.
This study investigated Chinese dyslexic children’s efficiency in employing phonological strategies (i.e. the use of orthography-phonology correspondence rules) in reading and the effectiveness of training phonological strategies in improving Chinese dyslexic children’s reading performance. An Experimental Group of 15 Chinese dyslexic children received a five-day intensive training in phonological strategies while a comparable Control Group did not. The results showed that Chinese dyslexic children did not use the phonological strategies as efficiently as Chinese average readers, and the training programme was effective in significantly improving the Experimental Group’s reading performance. This suggests that Chinese dyslexic children can benefit from training in phonological strategies.  相似文献   

15.
In a longitudinal study of the relation between preschool development and later reading abilities, children with dyslexic parents and/or older siblings were compared to children with no family incidence of dyslexia. Many children from dyslexic families developed reading problems by the end of the second grade, and these poor readers were characterized chiefly by weaker early syntactic and phonological skills and by less frequent exposure to books during their preschool years than the preschoolers who became normal readers. Some implications of the results for etiological theories of dyslexia are discussed.  相似文献   

16.
Sixty children with dyslexia (41 boys, 19 girls; ages 9 to 13) were enrolled in a 10-week summer tutoring program that emphasized word-building skills. They were randomly and blindly assigned to receive either placebo or piracetam, a purportedly memory-enhancing drug that has been reported to facilitate reading skill acquisition. The children were subtyped as "dysphonetic" or "phonetic" on the basis of scores from tests of phonological sensitivity and phoneme-grapheme correspondence skills. Of the 53 children who completed the program, 37 were classified as dysphonetic and 16 as phonetic. The phonetic group improved significantly more in word-recognition ability than the dysphonetic group. Overall, the children on medication did not improve more than the nonmedicated ones in any aspect of reading. The phonetic subgroup on piracetam gained more in word recognition than any subgroup but did not improve significantly more than the phonetic subgroup on placebo. Results are discussed in relation to findings from previous studies of piracetam in children with dyslexia.  相似文献   

17.
We combined independently the word length and word frequency to examine if the difficulty of reading material affects eye movements in readers of German, which has high orthographic regularity, comparing the outcome with previous findings available in other languages. Sixteen carefully selected German-speaking dyslexic children (mean age, 9.5 years) and 16 age-matched controls read aloud four lists, each comprising ten unrelated words. The lists varied orthogonally in word length and word frequency: high-frequency, short; high-frequency, long; low-frequency, short; low-frequency, long. Eye movements were measured using a scanning laser ophthalmoscope (SLO). In dyslexic children, fixation durations and the number of saccades increased both with word length and word frequency. The percentage of regressions was only increased for low-frequency words. Most of these effects were qualitatively similar in the two groups, but stronger in dyslexic children, pointing to a deficient higher-level word processing, especially phonological deficit. The results indicate that reading eye movements in German children are modulated by the degree of difficulty, and orthographic regularity of the language can determine the nature of modulation. The findings suggest that, similar to Italian but unlike English readers, German children prefer indirect sub-lexical strategy of grapheme-phoneme conversion.  相似文献   

18.
The aims of the study were to investigate whether children showing a low nonverbal/high verbal (LNV) WISC-R profile are more likely to exhibit behaviors conducive to school failure than children with a low verbal/high nonverbal (LV) profile, and to examine the relationships among these behaviors, the LNV/LV profiles, and reading ability. The 65 subjects included 27 LNV and 38 LV children, aged 5 to 11 years. Results confirmed earlier findings (Badian 1986) that LNV children are perceived by their teachers as significantly poorer than LV children in many behaviors associated with school success. There was a dichotomy, however, between LNV good and poor readers. All LNV subjects displayed problems in organizational skills, but those who were dyslexic were poorer in social behavior (e.g., acceptance of criticism and peer relationships) than either LNV good readers or LV good or poor readers. It was concluded that children with a low nonverbal/high verbal profile and a probable right hemisphere dysfunction, who appear to be dyslexic in the early school years, are at high risk for both social behavior problems and school failure, and that these children are a more high-risk group than poor readers with a low verbal/high nonverbal profile.  相似文献   

19.
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   

20.
Stress assignment to Italian polysyllabic words is unpredictable, because stress is neither marked nor predicted by rule. Stress assignment, especially to low frequency words, has been reported to be a function of stress dominance and stress neighbourhood. Two experiments investigate stress assignment in sixth-grade, skilled and dyslexic, readers. In Experiment 1, skilled readers were not affected by stress dominance. Dyslexic children, although affected by word frequency, made more stress regularisation errors on low frequency words. In Experiment 2, stress neighbourhood affected low frequency word reading irrespective of stress dominance for both skilled and dyslexic readers. Words with many stress friends were read more accurately than words with many stress enemies. It is concluded that, in assigning stress, typically developing and developmental dyslexic Italian readers are sensitive to the distributional properties of the language.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号