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1.
Jarkko Hautala Mikko Aro Kenneth Eklund Marja-Kristiina Lerkkanen Heikki Lyytinen 《Reading and writing》2013,26(6):845-864
The role of letters and syllables in typical and dysfluent second grade reading in Finnish, a transparent orthography, was assessed by lexical decision and naming tasks. Typical readers did not show reliable word length effects in lexical decision, suggesting establishment of parallel letter processing. However, there were small effects of word syllable structure in both tasks suggesting the presence of some sublexical processing also. Dysfluent readers showed large word length effects in both tasks indicating decoding at the letter-phoneme level. When lexical access was required in a lexical decision task, dyslexics additionally chunked the letters into syllables. Response duration measure revealed that dysfluent readers even sounded out the words in phoneme-by-phoneme fashion, depending on the task difficulty. This letter-by-letter decoding is enabled by the transparent orthography and promoted by Finnish reading education. 相似文献
2.
Despina Paizi Maria De Luca Pierluigi Zoccolotti Cristina Burani 《Journal of Research in Reading》2013,36(3):303-329
Italian developmental dyslexic readers show a striking length effect and have been hypothesised to rely mostly on nonlexical reading. Our experiments tested this hypothesis by assessing whether or not the deficit underlying dyslexia is specific to lexical reading. The effects of lexicality, word frequency and length were investigated in the same group of children in four separate experiments. Although dyslexics were slower and less accurate than skilled readers and had large length effects, they showed lexicality and word frequency effects in both reading aloud and lexical decision. In a cross‐experiment comparison, we show that a single global factor explains a large proportion of the difference in reading performance between dyslexic and skilled readers. This factor may indicate a deficit at a prelexical level of analysis. Lexical activation seemed spared in the dyslexic children based on the effects of lexicality and frequency. These findings contrast the hypothesis that Italian dyslexics primarily engage in nonlexical reading. 相似文献
3.
Dyslexic children (n=21, mean age=10.2 years) were compared with normal readers of the same age, normal readers of the same reading-age, and poor readers of the same reading-age on measures of phonological decoding and automatic word processing. Three different tasks, varying in phonological demand, were used: a naming task, an auditory-visual matching task, and a lexical decision task. On each task, word-pseudoword profiles were obtained to test phonological decoding skills and unspeeded-speeded profiles were assessed to test automaticity in word processing. Main results indicated that dyslexics have a deficit in automatic phonological decoding skills. The results are discussed within the framework of the phonological deficit and the automatization deficit hypothesis. 相似文献
4.
《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
5.
John M. Reddington Kel D. Cameron 《International Journal of Disability, Development & Education》1991,38(2):171-203
THIS DOUBLE‐BLIND experiment investigated various aspects of visual and auditory problems related to dyslexia. Seventeen children with dyslexia aged 7.25 to 10.25 years were compared with 17 normal readers matched for CA and intellectual ability. A speech perception task which measured the subjects’ auditory threshold level significantly separated the two groups. No difference was found when this task was performed at 35 dB above individual threshold levels. A significant difference between groups was found for the Form Constancy Subtest of the Frostig Developmental Test of Visual Perception (DTVP) (1966). A significant negative correlation found between these measures for the dyslexics, but not for the normal readers, supports previous evidence for auditory and visual subtypes in dyslexia. Various optometric measures were also examined. Four dyslexics, but no normal readers, suffered fixation disparity. This difference was significant. Six representative subjects of each group were compared for eye tracking in reading. The word span of the dyslexics was significantly smaller than that of the normal readers. A multiple discriminant analysis incorporating the auditory threshold task, form constancy, fusional reserves (distance, negative), accommodation right eye and heterophoria significantly discriminated the two reading groups. The perceptual variables were more heavily weighted than the optometric measures. It was concluded that while eye tracking and binocular fusion problems should always be considered in the assessment of dyslexics, factors involved in information processing in auditory and visual perception appear to be those which are more highly implicated. 相似文献
6.
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
7.
Cross-linguistic studies suggest that the orthographic system determines the reading performance of dyslexic children. In opaque orthographies, the fundamental feature of developmental dyslexia is difficulty in reading accuracy, whereas slower reading speed is more common in transparent orthographies. The aim of the current study was to examine the extent to which different variables of words affect reaction times and articulation times in developmental dyslexics. A group of 19 developmental dyslexics of different ages and an age-matched group of 19 children without reading disabilities completed a word naming task. The children were asked to read 100 nouns that differed in length, frequency, age of acquisition, imageability, and orthographic neighborhood. The stimuli were presented on a laptop computer, and the responses were recorded using DMDX software. We conducted analyses of mixed-effects models to determine which variables influenced reading times in dyslexic children. We found that word naming skills in dyslexic children are affected predominantly by length, while in non-dyslexics children the principal variable is the age of acquisition, a lexical variable. These findings suggest that Spanish-speaking developmental dyslexics use a sublexical procedure for reading words, which is reflected in slower speed when reading long words. In contrast, normal children use a lexical strategy, which is frequently observed in readers of opaque languages. 相似文献
8.
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
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.
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
11.
Some previous studies of visual word recognition have reported an interaction between visual field and word length (measured by number of letters), such that recognition is affected more by word length for words presented in the left than for words presented in the right visual field. However, when manipulating serial position of letters in words to measure length effects, there are also reports of symmetrical word length effects in the two visual fields. Here we report two experiments, presenting four‐ and seven‐letter words, suggesting that the serial position and length effects in the hemispheres are separable and task dependent. For tasks that rely more heavily on letter‐level processing such as letter search (Experiment 1), performance in both hemifields showed similar effects of serial position; however, when comparing four‐ and seven‐letter words, an effect of word length was evident only in the left visual field, in line with the well‐established interaction between word length and hemifield. An interaction between word length and hemifield was confirmed for the same stimuli when they were employed in a lexical decision task, which forced whole‐word processing (Experiment 2). We conclude that the effects of serial position and number of letters in the two visual fields are separable, and are selectively affected by task type. 相似文献
12.
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
13.
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
14.
Phonological processing skills and deficits in adult dyslexics 总被引：13，自引：0，他引：13
This article presents 4 experiments aimed at defining the primary underlying phonological processing deficit(s) in adult dyslexia. 5 phonological processes, all involving spoken language, were studied: phoneme perception, phoneme awareness, lexical retrieval of phonology, articulatory speed, and phonetic coding in verbal short-term memory. 2 differently ascertained adult dyslexic groups, familial dyslexics (n = 15) and clinic dyslexics (n = 15), were the subjects in each experiment. These dyslexic groups were chosen because deficits that persist until adulthood and that are found in differently ascertained dyslexic groups are more likely to be primary. Each dyslexic group was compared to 2 control groups, chronological age (CA) controls who were similar in age and sex, and younger reading age (RA) controls who were similar in reading age and sex. The main finding was a clear deficit in phoneme awareness in both dyslexic groups, with each dyslexic group performing significantly worse than both CA and RA controls. Moreover, performance on the 2 phoneme awareness tasks together uniquely accounted for substantial variance in nonword reading. The clinic but not the familial dyslexics appeared to have an additional deficit in verbal short-term memory. No clear deficits were found in either dyslexic group in phoneme perception, lexical retrieval, or articulatory speed. 相似文献
15.
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
16.
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
17.
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
18.
This study examined the extent to which adultdyslexic readers exhibit concurrent deficitsfor phonological, orthographic and cross-modalword representations, and the relationshipbetween these deficits and decoding ability.Participants were 18 phonological dyslexics and19 normal readers at college level. Compared tonormal readers, dyslexics exhibitedsignificantly slower reaction times acrosstasks, and were less accurate on the unimodalorthographic task. Word pattern processing wasmore extensively related to decoding abilityamong dyslexic as compared to normal readers,but more robustly related to baseline measuresof phonological and orthographic processingamong normal readers. The results are discussedin the context of integrating the phonologicaland orthographic aspects of words, speed ofprocessing deficits, and the importance of taskselection when assessing adult dyslexicpopulations. 相似文献
19.
For the dyslexic and others with similar problems, it is suggested that the sequence of modalities known as VAKT be revised to achieve more effective and more rapid remediation. The new sequence is designated as TAK/v. The subordination of the visual modality is based on the recent identification of a visual processing deficiency in dyslexics, as well as on previous hypotheses, suggesting the desirability of substituting the tactile modality for the visual modality in the initial stages of remediation. The use of one hand is suggested for this tactile scanning of three-dimensional letters to access the right hemisphere, and experimental data are reported. 相似文献
20.
Juan L. Luque Miguel López-Zamora Carlos J. Álvarez Soraya Bordoy 《Annals of dyslexia》2013,63(3-4):239-252
This study explores whether activation and inhibition word processes contribute to the characteristic speed deficits found in transparent orthographies (Wimmer, Appl Psycholinguist 14:1–33, 1993). A second and fourth grade sample of normal school readers and dyslexic school readers participated in a lexical decision task. Words were manipulated according to two factors: word frequency (high vs. low) and syllable frequency (high vs. low). It has been repeatedly found that words with high-frequency syllables require extra time for deactivating the lexical syllabic neighbors: the so-called inhibitory effect of positional frequency syllable (Carreiras et al., J Mem Lang 32:766–780, 1993). We hypothesized that dyslexic readers would show a stronger inhibitory effect than normal readers because they are slower decoders and they may also be slower at the activation and inhibition of word representations that are competing (i.e., syllabic candidates). Results indicated an interaction between word and syllable frequency (i.e., a strong inhibitory effect was found in the low-frequency word condition). According to our hypothesis, the inhibitory effect size was almost three times bigger in dyslexics than in the normal readers. This difference shows an alteration, not a developmental lag. Interestingly, the inhibitory effect size did not interact with school grade. Thus, reading experience did not impact the lexical processes involved on the inhibitory effect. Our outcomes showed how activation and/or inhibition of lexical processes can contribute to the lack of speed beyond decoding deficit. 相似文献