Content uploaded by John Frederick Stein
Author content
All content in this area was uploaded by John Frederick Stein on May 31, 2018
Content may be subject to copyright.
A preview of the PDF is not available
On the relationship between dynamic visual and auditory processing and literacy skills; Results from a large primary-school study
Abstract and Figures
Three hundred and fifty randomly selected primary school children completed a psychometric and psychophysical test battery to ascertain relationships between reading ability and sensitivity to dynamic visual and auditory stimuli. The first analysis examined whether sensitivity to visual coherent motion and auditory frequency resolution differed between groups of children with different literacy and cognitive skills. For both tasks, a main effect of literacy group was found in the absence of a main effect for intelligence or an interaction between these factors. To assess the potential confounding effects of attention, a second analysis of the frequency discrimination data was conducted with performance on catch trials entered as a covariate. Significant effects for both the covariate and literacy skill was found, but again there was no main effect of intelligence, nor was there an interaction between intelligence and literacy skill. Regression analyses were conducted to determine the magnitude of the relationship between sensory and literacy skills in the entire sample. Both visual motion sensitivity and auditory sensitivity to frequency differences were robust predictors of children's literacy skills and their orthographic and phonological skills.
Figures - uploaded by John Frederick Stein
Author content
All figure content in this area was uploaded by John Frederick Stein
Content may be subject to copyright.
... Hence a visual M-deficit cannot be said to be the only cause of dyslexia (Skottun and Skoyles, 2004). Yet M-cell sensitivity predicts orthographic skill in both good and bad readers, whether or not they are classed as dyslexic (Talcott et al., 2002). Thus visual M-function appears to contribute significantly to everybody's ability to acquire reading skills. ...
... Thus, in many ways, auditory temporal processing impairments parallel those seen for the visual M-system in dyslexia, and suggest that both can contribute to causing dyslexia. Importantly, and probably as a result of their common genetic basis, these visual and auditory temporal processing deficiencies correlate strongly with each other in individuals tested for both (Talcott et al., 2002). Thus the majority of dyslexics appear to have both visual and auditory timing problems and their genetic basis probably represents the basic cause of their visual, phonological and reading difficulties. ...
Most of our knowledge about the neural networks mediating reading has derived from studies of developmental dyslexia (DD). For much of the 20th C. this was diagnosed on the basis of finding a discrepancy between children’s unexpectedly low reading and spelling scores compared with their normal or high oral and non-verbal reasoning ability. This discrepancy criterion has now been replaced by the claim that the main feature of dyslexia is a phonological deficit, and it is now argued that we should test for this to identify dyslexia. However, grasping the phonological principle is essential for all learning to read; so every poor reader will show a phonological deficit. The phonological theory does not explain why dyslexic people, in particular, fail; so this phonological criterion makes it impossible to distinguish DD from any of the many other causes of reading failure. Currently therefore, there is no agreement about precisely how we should identify it. Yet, if we understood the specific neural pathways that underlie failure to acquire phonological skills specifically in people with dyslexia, we should be able to develop reliable means of identifying it. An important, though not the only, cause in people with dyslexia is impaired development of the brain’s rapid visual temporal processing systems; these are required for sequencing the order of the letters in a word accurately. Such temporal, “transient,” processing is carried out primarily by a distinct set of “magnocellular” (M-) neurones in the visual system; and the development of these has been found to be impaired in many people with dyslexia. Likewise, auditory sequencing of the sounds in a word is mediated by the auditory temporal processing system whose development is impaired in many dyslexics. Together these two deficits can therefore explain their problems with acquiring the phonological principle. Assessing poor readers’ visual and auditory temporal processing skills should enable dyslexia to be reliably distinguished from other causes of reading failure and this will suggest principled ways of helping these children to learn to read, such as sensory training, yellow or blue filters or omega 3 fatty acid supplements. This will enable us to diagnose DD with confidence, and thus to develop educational plans targeted to exploit each individual child’s strengths and compensate for his weaknesses.
... Indeed, there have been several experiments that have demonstrated that dyslexics have decreased sensitivity while participating in the coherent motion perception test, a test that helps determine the global perception of motion by evaluating the "motion coherence threshold" [16][17][18]. The lower the number of signal dots required to visualize a moving form, the lower the threshold, and the more sensitive the viewer is to global motion [19]. ...
... Though there was no difference in how each group viewed the forms moving, given their abnormal visuomotor profile, it may be possible that their visual instability may have influenced their sensitivity to visual motion. This contradicts some previous findings that dyslexics have a higher threshold for global motion, though our study focuses more on the illusion of movement in depth compared with previous studies [16][17][18]. Our findings suggest dyslexics may be more sensitive to movement in depth, which could be related to their instability in vergence eye movements. ...
Op art was created, in part, to produce illusions of movement. Given that dyslexics have been shown to have impaired visuo-postural axis deficits, it may be possible that dyslexics see illusions different than their non-dyslexic peers. To test this theory, we measured eye movement and posture in 47 dyslexic (18 female, 29 male; mean age 15.4) and 44 non dyslexic (22 female, 22 male; mean age 14.8) adolescents while they viewed three works of art by Op artist Bridget Riley. They then responded to a questionnaire about how they felt while viewing the artworks. Dyslexics demonstrated significantly slower saccades in terms of average velocity that was particularly disturbed in paintings that manipulated depth. Subjectively, dyslexics felt much more destabilized compared to their peers; however, there was not a significant difference in objective postural measurements between the two groups. The sensation of destabilization was positively correlated with appreciation in non-dyslexic adolescents. These subjective results suggest that dyslexics may be more sensitive to movement in depth, which could be related to the instability in vergence movements. Whereas this instability represents a hinderance in relation to reading, it could be an advantage while viewing paintings such as these.
... Frequency discrimination (FD), the ability to detect frequency differences between tones or sounds, is one of the various AP deficits linked to poor reading. Overall, the literature has documented an association between FD performance and phonological awareness and non-lexical reading [66][67][68][69][70][71][72]. Given that non-lexical reading and phonological awareness are critical to learning letter-sound correspondences, it is evident that FD, as a component of auditory processing, is an essential area to formally evaluate in children with SSD. ...
Background:
Speech-sound disorders (SSD) have been linked to auditory processing difficulties, and auditory processing disorders (APD) have been related to phonological awareness and literacy development. To this date, there has not been a systematic literature review investigating the results of psychophysiology and language assessments related to SSD and APD in children.
Methods:
The literature search was conducted in PubMed, Medline EBSCO, and Scopus to identify studies with children diagnosed/suspected of having APDs and SSDs. The quality of methodology in the selected articles was evaluated with the Newcastle Ottawa Scale.
Results:
Seven out of 378 relevant studies met the selection criteria. The findings were summarized for children with SSD and APD based on (a) metalinguistic and literacy skills, (b) cognitive abilities, and (c) temporal processing abilities. Three articles indicated that children with APD and SSD exhibit lower temporal task accuracy and reaction time. In two studies, children with SSD exhibited lower scores in discrimination, sequencing, and recall of brief stimuli in rapid succession.
Conclusions:
This review revealed associations between SSD severity and APD that may underline low performance in metalinguistic skills. Diagnostic assessments have been proposed based on the review to adequately identify children with SSD and APD and provide useful information for more suitable intervention.
... It is noteworthy that reading learning has a strong relationship with writing ability [42]. The reading performance also requires visual attention and visual processing, and teaching visual perception skills improves the reading performance of dyslexic students [43,44]. It can now be said that the set of skills of visual perception, perception of body position, necessary strength, and skill of hand and eye-hand integration requires the integration of senses, including touch, visual, proprioception, and vestibular. ...
Introduction: Identifying the contributing factors to a specific learning disorder and comparing these factors in different types of this disorder will lead to using more proper interventions in the future. Therefore, this study aimed to compare sensory processing skills and perceived motor competence between three groups of students with specific learning disabilities (reading and writing disorders, math disorders, and combination disorders).
Materials and Methods: The present study was a cross-sectional descriptive-analytical study. The participants were 48 children (16 in each group, aged 8-12 years). They were selected from Chaharmahal and Bakhtiari Province, Iran, by the simple convenience sampling method. The participants’ sensory processing was measured with sensory profile 2 and their perceived motor competency with Marsh perceived motor competence questionnaire.
Results: The results showed a significant difference between the three groups in the sensory sensitivity, low registration sensory patterns and processing of tactile, and body position senses (P 0.05).
Conclusion: The results indicate that therapeutic interventions in the group with reading and writing disorders should focus on increasing sensory registration and processing of tactile and body position senses and reducing sensory sensitivity in the mathematical group.
... Concerning the link between visual and auditory sensitivities, a total of 10 studies were identified (see Appendix B, Table B1). Intriguingly, three of these studies indicated the conjoint role of both visual and auditory sensitivities to predict one's literacy skills or predisposition to develop specific pathologies (King et al., 2007;Ramsay et al., 2020;Talcott et al., 2002). Additionally, four studies supported the concept of consistencies across sensitivities to visual and auditory stimuli, with these two senses sharing common sensory processes (Barne et al., 2018;Gunn & Loeb, 1967;Stevenson, 1918;Woodward et al., 1976). ...
Understanding how human senses are linked to eating behaviour and adiposity has been a key topic in sensory science, and a source of substantial controversy. Despite strong correlations in sensitivity across different sensory modalities, the fundamental question of whether individuals possess a ‘generalised sensitivity’ across senses remains unanswered. A better understanding of the relationships between multiple senses and eating behaviour is needed to tackle the current obesity epidemic. The present study synthesises published data regarding sensory sensitivities across modalities and presents new empirical findings. Specifically, we synthesise findings from 115 publications, including meta-analyses of 26 studies. These data reveal strong yet complex links between senses, highlighting the potential of multi-sensory analyses to better characterise sensory variations. In the empirical study, 98 Caucasian males (25.9 ± 5.8 years of age; body mass index: 26.8 ± 5.1 kg∙m⁻²) are tested for their supra-threshold sensory sensitivities (d’) to 11 food-related mono-modal stimuli across olfaction, gustation, vision, and audition. Canonical correlations on d’ for each modality reveal significant positive correlations between olfaction and gustation (p < 0.001), vision and audition (p < 0.001), as well as olfaction and audition (p = 0.008). Additionally, K-means cluster analysis identifies three broad groups of individuals with distinct multi-sensory fingerprints. Intriguingly, individuals in separate clusters are shown to have significantly different adiposity measures (body mass index: p = 0.01; body fat percentages: p = 0.05). Overall, this study sheds important new light on multi-sensory ‘fingerprints’, and their links to obesity.
... It is worth pointing out that the attentional orienting system is anatomically based in the parietal dorsal stream, which in turn, has strong input from the magnocellular system (Gori and Facoetti, 2015). Several studies have shown temporal deficits in DD often suggested to be associated with magnocellular dysfunction (Livingstone et al., 1991;Cornelissen et al., 1995;Stein and Walsh, 1997;Iles et al., 2000;Talcott et al., 2002;Laycock et al., 2012;Pina Rodrigues et al., 2017b) and, in an important recent study, it has been demonstrated a causal link between magnocellular deficits and DD (Gori et al., 2016). Hari and Renvall (2001) proposed that parietal attentional dysfunction could underlie such deficits. ...
Purpose: Abnormal exogenous attention orienting and diffused spatial distribution of attention have been associated with reading impairment in children with developmental dyslexia. However, studies in adults have failed to replicate such relationships. The goal of the present study was to address this issue by assessing exogenous visual attention and its peripheral spatial distribution in adults with developmental dyslexia.
Methods: We measured response times, accuracy and eye movements of 18 dyslexics and 19 typical readers in a cued discrimination paradigm, in which stimuli were presented at different peripheral eccentricities.
Results: Results showed that adults with developmental dyslexia were slower that controls in using their mechanisms of exogenous attention orienting. Moreover, we found that while controls became slower with the increase of eccentricity, dyslexics showed an abnormal inflection at 10° as well as similar response times at the most distant eccentricities. Finally, dyslexics show attentional facilitation deficits above 12° of eccentricity, suggesting an attentional engagement deficit at far periphery.
Conclusion: Taken together, our findings indicate that, in dyslexia, the temporal deficits in orientation of attention and its abnormal peripheral spatial distribution are not restricted to childhood and persist into adulthood. Our results are, therefore, consistent with the hypothesis that the neural network underlying selective spatial attention is disrupted in dyslexia.
... Auditory processing skills are essential for language acquisition and language-related skills such as phonological awareness. Intact auditory processing leads to the development of phonological awareness skills via the formation of phonemic representations (Talcott et al., 2000(Talcott et al., , 2002Tallal, 2004;Pasquini et al., 2007;Poelmans et al., 2011). Indeed, associations between auditory processing and phonological awareness have been observed in all ages from infants to adults Poelmans et al., 2011;Law et al., 2014). ...
Perception of low-level auditory cues such as frequency modulation (FM) and rise time (RT) is crucial for development of phonemic representations, segmentation of word boundaries, and attunement to prosodic patterns in language. While learning an additional language, children may develop an increased sensitivity to these cues to extract relevant information from multiple types of linguistic input. Performance on these auditory processing tasks such as FM and RT by children learning another language is, however, unknown. Here we examine 92 English-speaking 7–8-year-olds in the U.S. and their performance in FM and RT perceptual tasks at the end of their second year in Cantonese or Spanish dual-language immersion compared to children in general English education programs. Results demonstrate that children in immersion programs have greater sensitivity to FM, but not RT, controlling for various factors. The immersion program students were also observed to have better phonological awareness performance. However, individual differences in FM sensitivity were not associated with phonological awareness, a pattern typically observed in monolinguals. These preliminary findings suggest a possible impact of formal language immersion on low-level auditory processing. Additional research is warranted to understand causal relationships and ultimate impact on language skills in multilinguals.
Dorsal stream is an important pathway for visual information transmission. As a part of the dorsal pathway, the middle temporal visual motion areas (V5/MT+) are mainly responsible for visual motion processing and the ability of visual motion processing is closely related to reading. Compared with alphabetic scripts, the visual structure of Chinese characters is more complex and there are no clear grapheme‐phoneme correspondence rules. So the ability of visual analysis plays an important role in Chinese character processing. This study first investigated the brain activation of Chinese dyslexic children and children of the same chronological age when they observed coherent motion stimuli. ROI analysis indicated that only the activation of left V5/MT+ was significantly weaker in dyslexics than that in the control group. The activity of the magnocellular‐dorsal stream was closely related to orthographic awareness in the combined data (two groups) and the typical children. In dyslexia group, the stronger the activation of V5/MT+ was, the worse the phonological awareness, rapid naming performance and orthographic awareness were. In short, Chinese dyslexic children were deficient in the activation of the left V5/MT+ and the activity of the magnocellular‐dorsal pathway was closely related to orthographic awareness in Chinese pupils.
Magnocellular (M) deficit theory indicates that individuals with developmental dyslexia (DD) have low sensitivity to stimuli with high temporal frequencies (HTF) and low spatial frequencies (LSF). However, some studies found that temporal processing and spatial processing were correlated with different reading‐related skills. Chinese is a logographic language, and visual skills are particularly important for reading in Chinese. It is necessary to investigate the temporal and spatial processing abilities in the M pathway of Chinese children with DD. Using electrophysiological recordings, the present study examined the mean amplitude and latency of P1 during a grating direction judgment task in 13 children with DD and 13 age‐matched normal children. Dyslexic children showed a low amplitude and long latency of P1 in the HTF condition and LSF condition compared with age‐matched children. In the HTF condition, the amplitude of P1 correlated with phonological awareness, and the latency of P1 correlated with reading fluency and rapid naming of digits. The amplitude of P1 in the LSF condition correlated with reading accuracy. This result suggested that Chinese children with DD had difficulties in both temporal and spatial processing in the M pathway. However, temporal processing and spatial processing played different roles in Chinese reading.
Objective
The purpose of the study was to examine the effects of language experience on selective auditory attention and speech-in-noise perception in English Second Language (ESL) learners aged seven to eight years.
Method
A quantitative, descriptive, comparative cross-sectional research design was used to determine the effect of age of exposure to English on the selective auditory attention abilities and speech-in-noise perception skills of 40 children with normal hearing in first or second grade (aged seven to eight years). The control group comprised of 20 English first language (EFL) learners (mean age = 7.35 years ±0.49) and the research group included 20 s language learners (mean age = 7.70 years ±0.47). In order to compare the control and research groups with respect to the age of exposure to English through various sources, the Mann Whitney test was used. Information regarding the age of exposure was gathered by a case history questionnaire, completed by the parents/guardians of the participants. The Selective Auditory Attention Test (SAAT) and Digits-in-Noise (DIN) test were performed in one sitting.
Results
No statistically significant differences between the EFL and ESL groups were found for the SAAT and DIN. However, a statistically significant difference was obtained between the SAAT lists 1 and 3 & the DIN: diotic listening condition for the ESL group only (rs = −0.623; p = 0.003). The difference between the EFL and ESL groups in the mean age of exposure to English was statistically significant (p = 0,019), with mean age of exposure to English in the ESL group (mean age = 2.82 ± 0.53) being higher than the mean age of exposure in the EFL group (mean age = 1.81 ± 1.53). However, this difference did not influence the results of the SAAT and DIN significantly.
Conclusion
The main finding was that selective auditory attention and speech-in-noise perception were not significantly affected in the ESL learners who participated in the study – learners who were recruited from private schools located in an urban area and thus from higher socio-economic status (SES) households. There is a need for additional research with a larger sample size to determine the selective auditory attention abilities and speech-in-noise perception skills of ESL learners in government-funded schools located in rural areas and from various socio-economic backgrounds.
Three bodies of research that have developed in relative isolation center on each of three kinds of phonological processing: phonological awareness, awareness of the sound structure of language; phonological recoding in lexical access, recoding written symbols into a sound-based representational system to get from the written word to its lexical referent; and phonetic recoding in working memory, recoding written symbols into a sound-based representational system to maintain them efficiently in working memory. In this review we integrate these bodies of research and address the interdependent issues of the nature of phonological abilities and their causal roles in the acquisition of reading skills. Phonological ability seems to be general across tasks that purport to measure the three kinds of phonological processing, and this generality apparently is independent of general cognitive ability. However, the generality of phonological ability is not complete, and there is an empirical basis for distinguishing phonological awareness and phonetic recoding in working memory. Our review supports a causal role for phonological awareness in learning to read, and suggests the possibility of similar causal roles for phonological recoding in lexical access and phonetic recoding in working memory. Most researchers have neglected the probable causal role of learning to read in the development of phonological skills. It is no longer enough to ask whether phonological skills play a causal role in the acquisition of reading skills. The question now is which aspects of phonological processing (e.g., awareness, recoding in lexical access, recoding in working memory) are causally related to which aspects of reading (e.g., word recognition, word analysis, sentence comprehension), at which point in their codevelopment, and what are the directions of these causal relations?
Researchers have taken two somewhat different views regarding the nature and development of orthographic and phonological knowledge in spelling and reading. A strongly integrative view holds that development in both areas depends on a common underlying knowledge base. For example, Ehri (1989, 1992) has argued that alphabetic “orthographic images” involved in both reading and spelling are amalgamated with the phonological information pertaining to the word (see also, Barron, 1986; Goswami & Bryant, 1990; Stuart & Coltheart, 1988). A more separatist view is represented in “dual-route” theories that emphasize the independence of two routes to the lexicon; an indirect phonological-decoding route operating through the reader’s knowledge of grapheme-phoneme correspondences, and a direct “visual” route that uses orthographic knowledge to access the lexicon without phonological mediation (Coltheart, 1978; Morton, 1969). The “dual-route” view has been very influential in attempts to account for individual differences in acquired and developmental reading disorders (Boder, 1973; Castles & Coltheart, 1993; Coltheart, Curtis, Atkins, & Haller, 1993; Mitterer, 1982; Patterson, Marshal, & Coltheart, 1985; Seymour, 1986), as well as individual differences across the normal continuum of reading ability (Baron, 1979; Baron & Strawson, 1976; Freebody & Byrne, 1988; Treiman, 1984). In this chapter we selectively review earlier research and present new behavioral-genetic evidence on the degree of developmental independence between disabled readers’ skills in the indirect (phonological) and direct (orthographic) routes for the identification of printed words.
Quantitative predictions are made from a model for word recognition. The model has as its central feature a set of "logogens," devices which accept information relevant to a particular word response irrespective of the source of this information. When more than a threshold amount of information has accumulated in any logogen, that particular response becomes available for responding. The model is tested against data available on (1) the effect of word frequency on recognition, (2) the effect of limiting the number of response alternatives, (3) the interaction of stimulus and context, and (4) the interaction of successive presentations of stimuli. Implications of the underlying model are largely upheld. Other possible models for word recognition are discussed as are the implications of the logogen model for theories of memory. (30 ref.) (PsycINFO Database Record (c) 2012 APA, all rights reserved)
We assess evidence and arguments brought forward by Tallal (e.g., 1980) and by the target paper (Farmer & Klein, 1995) for a general deficit in auditory temporal perception as the source of phonological deficits in impaired readers. We argue that (1) errors in temporal order judgment of both syllables and tones reflect difficulty in identifying similar (and so readily confusable) stimuli rapidly, not in judging their temporal order; (2) difficulty in identifying similar syllables or tones rapidly stem from independent deficits in speech and nonspeech discriminative capacity, not from a general deficit in rate of auditory perception; and (3) the results of dichotic experiments and studies of aphasics purporting to demonstrate left-hemisphere specialization for nonspeech auditory temporal perception are inconclusive. The paper supports its arguments with data from a recent control study. We conclude that, on the available evidence, the phonological deficit of impaired readers cannot be traced to any co-occurring nonspeech deficits so far observed and is phonetic in origin, but that its full nature, origin, and extent remain to be determined.
The existence of a phonemic deficit that is predictive of, and probably causal to, many cases of reading difficulty is well established. Tallal (1984) has suggested that this phonemic deficit is in fact a symptom of an underlying auditory temporal processing deficit. Our purpose in this paper is to evaluate the plausibility of this hypothesis. The various components that might constitute sequential (or temporal) processing are described. Our review of the literature reveals considerable evidence for a deficit in dyslexics in stimulus individuation tasks (e.g., gap detection) and temporal order judgments in both the auditory and visual modalities. The possibility that a general temporal processing deficit is associated with dyslexia, as suggested by Tallal (1984), is explored, and possible etiologies for such a deficit are discussed. The possibility of a causal link between temporal processing deficits and some reading disabilities is demonstrated, and converging evidence from morphological studies is reviewed. It is concluded that a temporal processing deficit does appear to be present in many developmental dyslexics, and strategies are suggested for further research aimed at evaluating the hypothesis that this deficit may be the root cause of a number of cases of dyslexia itself.
In a recent narrative review, Rack, Snowling, and Olson (1992) evaluated the hypothesis that dyslexic children have a specific deficit in phonological reading processes. To replicate, test, and extend their findings and speculations, the authors performed a quantitative meta-analysis with the same hypothesis and on the same database. Clear evidence for a modest difference (d=.48; N=1183) between dyslexics and reading-level-matched normal readers on nonword reading tasks was found. The nonword reading deficit in developmental dyslexia should be considered an established fact, although its contribution to the explanation of dyslexia is not large (less than 6% of the variance). Contrary to Rack et al. (1992), the major weaknesses of studies not finding a significant deficit did not appear to be the type of nonword reading test, the age of the normal readers, or the dyslexics' participation in special remediation programs. The adequacy of the matching procedure in terms of differences in age and intelligence and in word recognition ability was more important. /// [French] Dans une récente revue de question de type narratif, Rack, Snowling et Olson (1992) ont évalué l'hypothèse que les enfants dyslexiques ont un déficit spécifique dans les processus de lecture phonologique. Pour répliquer, tester et étendre ces conclusions et ces réflexions, les auteurs du présent texte ont réalisé une méta-analyse quantitative avec la même hypothèse et la même base de données. Ils ont clairement établi l'existence d'une différence modeste (d=.48; N=1183) entre des dyslexiques et des lecteurs normaux qui avaient été appariés selon l'âge de lecture dans des tâches de lecture de non mots. On devrait donc considérer comme un fait établi l'existence du déficit des enfants dyslexiques dans la lecture de non mots, quoique sa contribution à l'éxplication de la dyslexie ne soit pas grande: moins de 6% de la variance. Contrairement à Rack et al. (1992), les faiblesses majeures des études qui ne trouvent pas de différence significative n'apparaissent pas être le type de test de lecture de non mots, l'âge des lecteurs normaux, ou la participation des dyslexiques à des programmes particuliers de rééducation. Ce qui est apparu plus important est l'adéquation de la procédure d'appariement des enfants en termes de différences d'âge et d'intelligence, et en capacité de reconnaissance des mots. /// [Spanish] En una revisión reciente, Rack, Snowling y Olson (1992) evaluaron la hipótesis de que los niños disléxicos tienen un déficit específico en los procesos fonológicos de la lectura. Para replicar, probar y extender estos hallazgos y especulaciones, los autores hicieron un meta-análisis cuantitativo con la misma hipótesis y la misma base de datos. Se encontró evidencia clara de una leve diferencia (d=.48; N=1183) entre disléxicos y lectores normales, apareados por nivel de lectura, en tareas de lectura de pseudopalabras. El déficit en lectura de pseudopalabras en la dislexia evolutiva debe ser considerado un hecho establecido, si bien la contribución de este hecho a la explicación de la dislexia no es grande (menos del 6% de la varianza). Contrariamente a lo propuesto por Rack et al. (1992), la debilidad principal de los estudios que no hallaron un déficit significativo, no fue el tipo de prueba de lectura de pseudopalabras, la edad de los lectores normales o la participación de los disléxicos en programas especiales de recuperación. La adecuación del procedimiento de apareamiento en términos de diferencias de edad e inteligencia y en habilidades de reconocimiento de palabras fue más importante. /// [German] In einer neueren Überblicksdarstellung evaluierten Rack, Snowling und Olson (1992) die Hypothese, daß lesegestörte Kinder einen spezifischen Mangel auf der phonologischen Ebene des Leseprozesses aufweisen. Um ihre Ergebnisse und Beobachtungen einschätzen, testen und erweitern zu können, unternahmen die Autoren eine quantitative Meta-Analyse mit derselben Hypothese und auf derselben Datenbasis. Es konnten deutliche Hinweise auf einen kleinen Unterschied (d=.48; N=1183) zwischen dem erreichten Level von Lesegestörten und dem normaler Leser von Texten gefunden werden. Das Textlesedefizit bei Leseentwicklungsstörung kann als Faktum angenommen werden, obwohl sein Erklärungsumfang nicht allzu weit reicht (weniger als 6% der Abweichung). Im Unterschied zu Rack u. a. (1992) schien die Hauptschwäche der Studien, die keinen signifikanten Mangel fanden, darin zu liegen, daß sie nicht den Textlesetest beinhalteten, das Alter der normalen Leser oder die Teilnahme lesegestörter Personen an speziellen Verbesserungsprogrammen. Die Adäquanz der Erfolgsprozedur, gemessen an Alter, Intelligenz und Wortlernfähigkeit, war vorher wichtiger.
Fourteen twin pairs, aged 8 to 10 years, were tested 3 times over 12 months; they included 11 children with language impairment (LI), 11 control children matched on nonverbal ability and age, and 6 co-twins who did not meet criteria for LI or control status. Thresholds were estimated for detecting a brief backward-masked tone (BM), detection of frequency modulation (FM), and pitch discrimination using temporal cues (Δf0). Both BM and FM thresholds improved with training, and by the 2nd test session, FM thresholds were in the adult range. There were marked individual differences on BM and Δf0, and, for both tasks, performance correlated with Tallal's Auditory Repetition Task administered 2 years previously. However, no auditory measure gave significant differences between LI and control groups; performance was influenced more by nonverbal than language ability. Some children did have a stable pattern of poor performance on certain auditory tasks, but their good FM detection raised questions about whether processing of auditory temporal information is abnormal. We found no evidence that auditory deficits are a necessary or sufficient cause of language impairments.
Our sample consisted of 420 children who were making normal progress in learning to read (35 girls and 35 boys at each of the ages from 7 to 12 years inclusive, from a variety of schools in Sydney). They were given a set of 30 exception words, 30 nonwords, and 30 regular words to read aloud. As predicted by a dual-route account of learning to read, the correlations between regular word and exception word reading accuracy and between regular word and nonword reading accuracy were higher than the correlation between exception word and nonword reading accuracy; also as predicted by this account, regular word reading accuracy was higher than exception word and nonword reading accuracy.We present our data as age-related norms which can be used in conjunction with our materials to assess how well children in this age range who appear to have reading difficulties are acquiring the lexical and nonlexical reading procedures as they learn to read.
