What is dyslexia?
- It is neurobiological in origin. Simply put, individuals who have dyslexia use different areas of their brain to process language than non-dyslexic individuals.
- It involves an unexpected discrepancy between an individual’s cognitive ability and reading ability.
- Is marked by challenges with speed and accuracy of word decoding.
- Poor spelling and comprehension are also often associated with dyslexia.
- There are multiple theories of dyslexia but the most widely accepted theories implicate phonological processing and rapid automatized naming (RAN).
- A phoneme is an individual unit of sound (eg: /c/, /sh/). Phonological processing includes the ability to isolate and manipulate units of sound.
- Rapid automatized naming is as it sounds: the ability to rapidly identify objects, letters, etc.
How common is dyslexia?
The prevalence is higher (50%) for individuals with a first degree relative (parent or sibling) with dyslexia (Vogler, DeFries & Decker, 1985).
Can dyslexia be diagnosed before a child is old enough to read?
- Dyslexia is neurobiological and, as such, indicators of risk can be present regardless of a child’s age or literacy progress. Pre-literacy diagnoses are not common, but researchers such as John Gabrieli and Nadine Gaab are expanding the research in this area.
Can intervention begin before a child is old enough to read?
Yes! Intervention can and should begin prior to literacy!
Why is early intervention so important?
Language development happens in what is referred to as a “sensitive period.” This can be thought of a ‘window of opportunity.’ Although neuroplasticity enables brains of all ages to continue to change and develop, the most ‘bang for your buck’ happens during a sensitive period.
Think about a child who learns to speak two languages as compared to someone who learns a second language as an adult. Both the child and the adult are capable of learning another language, but the child, who is still in the sensitive period for language development, will be able to speak this second language without an accent, whereas the adult will not.
The sensitive period for language goes until roughly the end of second grade. Thus, the more intervention that can be given prior to that, the more long-lasting and far-reaching the intervention will be. It’s important not to wait for a post-literacy diagnosis before beginning intervention because, by that time, the child will be through or nearly through the sensitive period for language development. When in doubt, intervene, and intervene early.
Who should receive early intervention?
- Children who have first degree relatives (parents or siblings) with dyslexia. In communication with Dr. Nadine Gaab, she has indicated that for such children she would begin intervention even before warning signs emerge or testing has been done. This allows for maximum intervention during the sensitive period of language development.
- Children who have difficulties with sounds of language as indicated in typical preschool interactions (eg: rhyming, identifying words with the same initial sounds, etc.)
As indicated in the prior question, early intervention is essential. Thus, if in doubt, intervene!
- Ultimately, rapid automatized naming (RAN) is the best predictor of future reading (Wolf, p. 179) and is helpful for indicating who should receive early intervention. Difficulties in RAN can be visible at a young age (Wolf, p. 181, suggests three years old). Unfortunately, determination of RAN skills requires testing and is not visible organically through typical parenting or teaching.
A useful resource for identifying children who are at risk for dyslexia (due to low RAN or other deficits) is the DIBELS test. It is free and is available online here.
What should early intervention entail?
This is a bit difficult to generalize. Dyslexia can occur due to any of multiple deficits, and within those deficits, there are multiple sub-types. Dyslexia interventions need to address each student’s specific needs, although there are specific, overarching areas that should be included.
“Intervention for children with dyslexia should address the development of each of reading’s contributing components–from orthography and phonology to vocabulary and morphology–their connections, their fluency, and their integration in comprehension.”
Wolf, p. 195
In general, the more language exposure a child has, the better. For a pre-literate child, one can’t go wrong with practices such as the following:
- Practice anything that relates to the sounds. Eg: rhyming, identifying words that begin with the same initial sounds.
- Segmenting words into sounds. (Do this with sounds only, not letters. Once sounds are mastered, then the concept of letter-sound connections can be explored.) eg: What sounds are in cat? /k/, /ă/, /t/. How many sounds do you hear in box? Four: /b/ /ô/ /k/ /s/.
- Expose the pre-literate child to print. Anything that can help the child begin to understand that there is a connection between sounds and letters is beneficial. Ultimately, the child will need to understand that words are made of letters and letters represent sounds.
- Expose the pre-literate child to books. Reading to young children helps develop understanding of concepts like the directionality of print, that books have a right-side-up and an upside-down, and that pages are turned once words are read.
- Intentionally use rich vocabulary and explicitly teach vocabulary words to the child. Don’t water down vocabulary or use made-up words for children.
The importance of exposure to literature, of having others read to the child, of seeing others read, and so on, really cannot be understated. Home literacy practices can play an important role in mitigating the risk of dyslexia (Dilnot, Hamilton, Maughan, & Snowling, 2016; Powers, Wang, Beach, Sideridis, & Gaab, 2016).
Post-literacy intervention is also complex, but this page offers a helpful and brief synopsis. Interventions should involve systematic and explicit teaching of phonological processing and sound-letter connections (Wolf, p. 175).
Where can I read more?
The International Dyslexia Association is a great resource for current, reliable, and accessible information. Their fact sheets are nice for a quick look at specific topics, and this handbook entitled Dyslexia in the Classroom: What every teacher needs to know is great!
For an overview of the neuroscience of reading and dyslexia, I recommend Proust and the Squid: The story and science of the reading brain by Maryanne Wolfe. (See more information about this book in this previous blog post).
For connection with others who “aim to raise dyslexia awareness, empower families to support their children and inform policy-makers on best practices to identify, remediate and support students with dyslexia,” see if your province or state has a branch of Decoding Dyslexia.
Dilnot, J., Hamilton, L., Maughan, B., & Snowling, M. J. (2016). Child and environmental risk factors predicting readiness for learning in children at high risk of dyslexia. Development and Psychopathology,29(01), 235-244. doi:10.1017/s0954579416000134
Ozernov-Palchik, O., Yu, X., Wang, Y., & Gaab, N. (2016). Lessons to be learned: How a comprehensive neurobiological framework of atypical reading development can inform educational practice. Current Opinion in Behavioral Sciences, 10, 45-58. doi:10.1016/j.cobeha.2016.05.006
Powers, S. J., Wang, Y., Beach, S. D., Sideridis, G. D., & Gaab, N. (2016). Examining the relationship between home literacy environment and neural correlates of phonological processing in beginning readers with and without a familial risk for dyslexia: An fMRI study. Annals of Dyslexia, 66(3), 337-360. doi:10.1007/s11881-016-0134-2
Vogler, G. P., DeFries, J. C., & Decker, S. N. (1985). Family History as an Indicator of Risk for Reading Disability. Journal of Learning Disabilities, 18(7), 419-421. doi:10.1177/002221948501800711
Wolf, M. (2008). Proust and the Squid: The story and science of the reading brain. New York: Harper Perennial.