This session aims to provide an understanding of:
Overview of Dyslexia, definition and key characteristics
Cognitive theories of dyslexia
Phonological Deficit
Visual Deficit
Magnocellular Deficit
Central Executive Dysfunction
Cerebellum Dysfunction
What is Dyslexia
BPS (1999) defined dyslexia as severe and persistent reading difficulties in spite of appropriate learning opportunities
Does not distinguish from poor readers
Specific learning difficulty that is unexpected in relation to an individuals other cognitive abilities and attainments Discrepancy model (Lyon et al., 2003)
Tighter specification for research purposes
Educational psychologist may use BPS definition for intervention
Dyslexia is evident when accurate and fluent word reading/spelling develops very incompletely or with great difficulty. This focusses on literacy learning at the ‘word level' and implies the problem is severe and persistent despite appropriate learning opportunities"
British Psychological Society (1999). Dyslexia, Literacy and Psychological Assessment. Report of a Working Party of the Division of Educational and Child Psychology.
Key Characteristics
Decoding difficult - especially long or complicated words
Confusing sounds in words
Stumbling over words when speaking
High contrast text appears to move on the page
Not remembering things that you have just been
Key Characteristics
Difficulty doing mental arithmetic or solving problems in your head - Can be related to working memory.
Taking longer than most people to do the same tasks but do them just as well in the end
Reading is effortful and does not come automatically
Reading takes longer then most people
Prevalence/Persistence
Affects around 3-6% of children
More males than females
Dyslexia persists into adulthood
Reading accuracy and reading speed often reasonable by adulthood - spelling remains impaired
Comorbidity with other developmental disorders
Causes: Phonological Deficit Hypothesis
Reading and writing - extensions of spoken
communication
Related to a language skill.
The way that sound is processed is important in translating text to spoken sound.
Considerable research has shown a list of phonological processing deficits associated with dyslexia (Goswami, 2003)
Causes: Central Executive Dysfunction Hypothesis
Reader needs to focus attention on how text appears then shift attention to how word sounds.
The process of shifting attention is according to Baddeley and Hitch (1974) the role of the central executive - as this is responsible for allocating attention between cognitive tasks
Possible role of the frontal lobe
Deficits in frontal lobes or weakness in central executive could be possible cause of dyslexia
Comorbidity with other developmental disorders
PAPER
1. Speech-perception-in-noise deficits in dyslexia by Johannes C. Ziegler, Catherine Pech-Georgel, Florence George
2. Specifying theories of developmental dyslexia: a diffusion model analysis of word recognition by MaaikeH.T.Zeguers, PatrickSnellings, JurgenTijms, WouterD.Weeda, Peter Tamboer, Anika Bexkens and Hilde M. Huizengal
3. Rapid processing of letters, digits and symbols: what purely visual-attentional de?cit in developmental dyslexia? by Johannes C. Ziegler,Catherine Pech-Georgel,Ste ´phane Dufau1, and Jonathan Grainger
4. Facial speech gestures: the relation between visual speech processing, phonological awareness, and developmental dyslexia in 10-year-olds by Gesa Schaadt by Claudia M€ annel, Elke van der Meer, Ann Pannekamp2 and Angela D. Friederici
5. Practitioner Review: Reading disorders: what are the effective interventions and how should they be implemented and evaluated? by Fiona J. Duff and Paula J. Clarke
6. Early identi?cation and interventions for dyslexia: a contemporary view by Margaret J. Snowling