Dyslexia is Not a Myth.

Professor Margaret J. Snowling, University of York.

“There is strong scientific evidence concerning the nature, causes and consequences of dyslexia ….. its potentially negative effects can be ameliorated.”

As a Vice President of the BDA, I am saddened by the confusion and upset that has followed from the recent Dispatches programme entitled, ‘The Dyslexia Myth’. As someone who appeared in this programme I think it would be helpful to make the following points clear:

• My position in the debate about dyslexia.
• My understanding of the intended message of the programme.
• To preview my contribution to the forthcoming conference ‘The Death of Dyslexia’.

The Dyslexia Debate.

No one in the field of education would deny that there are myths surrounding dyslexia – dyslexia has been linked erroneously to left-handedness, balance deficits, persistence of infant reflexes, visual perceptual abnormalities and nutritional deficiencies. Similarly, it is not in doubt that the term ‘dyslexia’ is over-used. But this does not mean that dyslexia is a myth. On the contrary, there is strong scientific evidence concerning the nature, causes and consequences of dyslexia. Thus, dyslexia can be readily identified by educated professionals and its potentially negative effects can be ameliorated.

Modern conceptions of developmental disorder view such difficulties as dimensional rather than categorical. It is no longer relevant to ask ‘who is dyslexic and who is not’. Rather, the skills underlying the acquisition of reading are continuously distributed in the population, such that some people find learning to read and write a trivial matter whereas others, notably children with dyslexia, have extreme difficulty. Whether or not a child is diagnosed ‘dyslexic’ depends on their age and stage of development, the context and language in which they are learning and the criteria adopted by the educational system in which they are schooled. This does not mean that professionals should doubt their confidence to make a ‘diagnosis’. A reading of the scientific literature can guide them and more importantly, ensure that the ‘at-risk’ child gets the help they require, when they need it, so that the cruel reality of living with unrecognised dyslexia can be avoided.

There is now a massive consensus that learning to read depends upon phonological (speech) processing skills. Children who come to the task of learning to read with poor phonology are at high risk of dyslexia. Such children have difficulty learning letter sounds, in developing phoneme awareness and therefore in acquiring the alphabetic principle (phonics). If they do not receive intervention, they try to compensate by relying on visual skills, their reading and spelling development proceeds on the wrong trajectory and subsequently goes awry.

It is known with some certainty that the phonological skills that underlie reading development are highly heritable. A child’s genetic endowment plays an important role in determining how easily they will learn to read, all other things being equal. Furthermore it is important to note that phonological abilities do not depend on IQ - the genetic risk can affect learning to read in children of high and of low IQ equally though the problem is easier to detect in those of higher ability who do not show other learning problems. This does not mean however, that it will be easy to differentiate at school entry between children with dyslexia and children at risk of failure because they come to school from socio-economically or linguistically disadvantaged backgrounds. But this is where intervention programmes can make a difference. There is strong evidence that intervention programmes that target the development of phoneme awareness and letter-sound knowledge, in conjunction with reading practice from texts pitched at the appropriate level of difficulty, are effective in preventing the downward spiral of reading problems. Our research suggests that some 75% of children identified at risk of reading problems in Year 1 respond positively to such programmes. The remaining children continue to give cause for concern, and will include those with dyslexia whose problems are likely to persist.

A crucial question therefore is whether, if appropriate procedures for the identification, assessment and intervention of children at risk of reading problems were put in place in all schools, dyslexia would go away? The answer is quite simply no. Dyslexia is a brain-based disorder with consequences that persist from the pre-school years through to adulthood. Good teaching delivered at the right time will not eradicate the condition but it will greatly help these children learn to read and write and cope with the demands of our educational system. An analogy might be made with diabetes. An appropriate diet and the use of insulin undoubtedly helps people with this serious disease, but it will not cure it.

So What is Dyslexia?

• Developmental disorder with brain basis.
• Genetic origin.
• Characterised by phonological deficits.
• Primarily (but not exclusively) affects learning to read and spell.
• Characterised by poor verbal memory and poor phonological learning.
• Often affects development of arithmetic skills, foreign language learning, speech development, expressive language skills.
• May have knock-on effects on organisational skills and on confidence and self-esteem.
• Typically shows poor response to standard forms of literacy teaching.
• Life long condition but can be ameliorated.

Early Intervention Is Critical For Early Reading Difficulties To Prevent The Downward Spiral Of Dyslexia.

All of us in the field of dyslexia research, and all of the dyslexia community are committed to the implementation of early intervention programmes to ameliorate the consequences of dyslexia. In my view, the main aim of the recent programme was to make this point. The critical steps in the argument with which I agree were:

• dyslexia is not restricted to children of high IQ.
• it is known that dyslexia has a genetic basis but environmental causes are not ruled out and children with poor language development may also develop reading problems.
• there is good evidence for the efficacy of early intervention programmes that train phonological awareness in the context of highly systematic reading instruction.
• therefore a first line strategy should be to allow access for all poor readers to such intervention programmes.
• untreated reading problems can lead to a downward spiral of declining vocabulary, poor self-esteem and disaffection.

The programme was neither advocating that such programmes would ‘cure’ dyslexia, nor denying that people with dyslexia have problems other than reading. It was silent regarding children who do not respond to such interventions, and to the other problems that I outline above.

The Death of Dyslexia?

It should be clear from the above that the reason I agreed to speak at this conference was to ensure an even debate of viewpoints regarding the causes and consequences of dyslexia. For those who are interested, here is the abstract of my proposed presentation.

Redefining Dyslexia.

The definition of dyslexia is again under scrutiny. In this paper I will argue that current research clarifies its definition and is an important starting point for intervention. A large body of scientific evidence now shows that dyslexia is a neuro-developmental disorder with a genetic basis. Dyslexia is characterised by phonological processing impairments, evident across the life span, which affect reading acquisition. These may occur in the absence of other language deficits or in combination with more general delays in language and non-verbal skills. For those with severe phonological deficits, reading and spelling impairments may be persistent and resistant to treatment. Nevertheless, there is good evidence that early intervention can ameliorate reading difficulties and prevent the downward spiral of underachievement. Such intervention programmes should be implemented after the first year in school for all children whose reading development is delayed; further assessment and ongoing (and possibly intensive) support is necessary for those who fail to respond to such interventions.

The Way Forward?

The academic research community that I represent are committed to working in partnership with the British Dyslexia Association, the newly merged Dyslexia Institute-Hornsby International Organisation, other Dyslexia Organisations to convince policy makers of the importance of access to early intervention for all those at risk of dyslexia, and to ensure that appropriate provision is in place to address the ongoing needs of people with dyslexia.

Professor Margaret J. Snowling
University of York.
27 September 2005.