Phonological Deficit Traits in Verbal Language of Dyslexics (original) (raw)

The Studies about Phonological Deficit Theory in Children with Developmental Dyslexia: Review

Problem statement: Developmental Dyslexia (DD) or Reading Disability (RD) that was part of a larger heterogeneous group of learning disorders and characterized by unexpected problems in academic performance, despite average intelligence. Approach: Current opinions on the biological basis of dyslexia pointed to problems with phonological processing deficits with resulting poor phonemic awareness. Though there was much support for this hypothesis in the scientific literature, there remained an ongoing debate as to whether the core deficit was in fact a more general information processing problem that involves phonological awareness, phonological short-term memory, phonological re/de-coding (Rapid Automatized Naming, RAN). Results: Also double deficit hypothesis proposed that the dyslexic children impaired in word-identification accuracy or exhibiting slowly word decoding profile. Conclusion/Recommendations: The aim of this review was to present some of the most exciting researches on DD in the domains of phonological deficit theory that those will help future studies to follow.

Featuring Phonological Deficits in Dyslexics

ABSTRACT Many researchers accentuate on phonological deficit for cause of dyslexia [a reading disorder]. Studies related to the quest of phonological processing deficit in dyslexia are in process in western world. They suggest that children who present with significant delays in reading demonstrate performance weakness on phoneme discrimination and identification tasks. On the basis of cognitive model of lexical access, the present study focuses on phonological processing problems of Tamil dyslexics and identifies the specific aspects of phonological processing that may contribute to failure in reading. It also compares the phonological processing problems in their first language (Tamil) with that of second language (English).

Dyslexia Phonological Processing

This study analysed the performance of phonological processing, the diagnostic accuracy and the influence on reading in children who were native speakers of an orthography of intermediate depth. Portuguese children with developmental dyslexia (DD; N = 24; aged 10-12 years), chronological age (CA)-matched controls (N = 24; aged 10-12 years) and reading level (RL)matched controls (N = 24; aged 7-9 years) were tested on measures of phonological processing (phonological awareness, naming speed and verbal short-term memory) and reading. The results indicated that the children with DD performed significantly poorer in all measures compared with the CA and RL. Phonological awareness and naming speed showed a high accuracy (receiver operating characteristics curve analysis) for discriminating the children with DD from the CA and RL, whereas the presence of abnormally low scores in phonological awareness and naming speed was more frequent in the DD group than in the controls and the normative population. Hierarchical linear regression analyses revealed that phonological awareness was the most important predictor of all reading accuracy measures, whereas naming speed was particularly related to text reading fluency.

Common Misconceptions about the Phonological Deficit Theory of Dyslexia

Brain Sciences

In this discussion paper, I review a number of common misconceptions about the phonological deficit theory (PDH) of dyslexia. These include the common but mistaken idea that the PDH is simply about phonemic awareness (PA), and, consequently, is a circular “pseudo”-explanation or epiphenomenon of reading difficulties. I argue that PA is only the “tip of the phonological iceberg” and that “deeper” spoken-language phonological impairments among dyslexics appear well before the onset of reading and even at birth. Furthermore, not even reading-specific expressions of phonological deficits—PA or pseudoword naming, can be considered circular if we clearly distinguish between reading proper—real meaning-bearing words, or real text, and the mechanisms (subskills) of reading development (such as phonological recoding). I also explain why an understanding of what constitutes an efficient writing system explains why phonology is necessarily a major source of variability in reading ability and h...

Comparing the phonological and double deficit hypotheses for developmental dyslexia

2001

This study tested the predictions of the phonological and double deficit hypotheses by experimentally examining speech perception, phoneme awareness, lexical retrieval (serial and discrete), articulatory speed, and verbal STM in school age child (N = 35) and adolescent (N = 36) dyslexics, and both chronological age (CA) and reading age (RA) controls. The results confirmed the findings of previous studies of a deficit in phoneme awareness in developmental dyslexia. At both age levels, dyslexics performed significantly more poorly than both their CA and RA controls. Although deficits in the other processes investigated, particularly in rapid serial naming, were also apparent, they were not as clear-cut as the deficit in phoneme awareness. In general, definite evidence of a deficit in rapid serial naming was limited to the more severely impaired dyslexics. Furthermore, although rapid serial naming contributed independent variation to various literacy skills, its contribution was modest relative to the contribution of phoneme awareness, regardless of whether the literacy skill relied more or less heavily on phonological or orthographic coding skills. Further analyses suggested that variation in rapid serial skill is particularly important for fluent reading of text, whereas phoneme awareness is particularly important for the development of the ability to read by phonologically recoding letters or groups of letters in words into their phonological codes. This explains the relatively strong contribution of phoneme awareness to reading and spelling ability in general. In sum, the phonological hypothesis offers a more parsimonious account of the present results than the double deficit hypothesis.

Language Deficits in Dyslexic Children: Speech Perception, Phonology, and Morphology

Journal of Experimental Child Psychology, 2000

We investigated the relationship between dyslexia and three aspects of language: speech perception, phonology, and morphology. Reading and language tasks were administered to dyslexics aged 8 -9 years and to two normal reader groups (age-matched and reading-level matched). Three dyslexic groups were identified: phonological dyslexics (PD), developmentally language impaired (LI), and globally delayed (delay-type dyslexics). The LI and PD groups exhibited similar patterns of reading impairment, attributed to low phonological skills. However, only the LI group showed clear speech perception deficits, suggesting that such deficits affect only a subset of dyslexics. Results also indicated phonological impairments in children whose speech perception was normal. Both the LI and the PD groups showed inflectional morphology difficulties, with the impairment being more severe in the LI group. The delay group's reading and language skills closely matched those of younger normal readers, suggesting these children had a general delay in reading and language skills, rather than a specific phonological impairment. The results are discussed in terms of models of word recognition and dyslexia.

The phonological hypothesis of developmental dyslexia

Developmental dyslexia is currently hypothesized to rest on an impairment of phonological processing. Under such a hypothesis, the main diagnostic tool involves phonemes as subjects fail properly to associate them with their corresponding graphemes in reading. Although some phonological phenomena of either a subphonemic or supraphonemic character have also been identified by researchers, there does not seem to be a sustained attempt at dealing with the full range of phonological phenomena. This is all the more urgent as phonemes have long ceased to be of any theoretical interest to mainstream linguistic phonology. We present the preliminary results of a phonological case study of the reading performance of two Spanish-speaking children diagnosed with dyslexia, in which the emphasis is laid upon stress patterns and intonational contours. The results suggest that errors at the phonemic level may be as low as 3% in a text, whereas suprasegmental errors may range from 25% (incorrectly stressed single words) to 93% (intonationally incorrect sentences). Should further research confirm these results, then we would have to revise the content of the phonological hypothesis of developmental dyslexia and develop new and more realistic tools of assessment and treatment on the basis of current phonological theory.