Early Detection of Dyslexia: Genetics of Dyslexia Part 2
Frequently, children are suspected to be dyslexic learners after they are already enrolled in school and have been consistently demonstrating difficulties with reading and spelling. Once a parent or educator recognizes those difficulties, the children can be tested and receive educational accommodation.
But what if dyslexia could be discovered before children start school and well before they begin to fall behind? How early do the processing issues of dyslexia present themselves in a child’s life, and do those children with a family history of dyslexia merit special attention? Is it possible to make early detection of dyslexia happen even earlier?
In 2020, three scientists set out to answer these questions. The Australian Research Council awarded a grant to Marina Kalashnikova, Usha Goswami, and Denis Burnam of the MARCS Institute for Brain, Behaviour and Development, Western Sydney University, Sydney, New South Wales, Australia.
Their premise was this: early markers of later dyslexia will be present in infancy, especially in infants with a family history of dyslexia. The researchers assembled a group of nineteen-month-old infants, half of whom were genetically at risk for dyslexia by virtue of having one dyslexic parent, the other half of whom were not at risk.
The test involved learning new words by connecting them to their referent. An example of a word and its referent is the word dog, and a picture of a dog. Both indicate the same information, one in written form and the other in pictorial form.
The researchers were looking for connections between how each group processed sound (auditory development) and phonological awareness, or the ability to organize the sounds of their language. These two aspects, the researchers felt, would impact a child’s lexical development.
According to the Encyclopedia of Lexical Development, “Lexical development is the study of changes that occur in vocabulary knowledge over childhood. It concerns children’s first steps in building a vocabulary, how children of different ages assign meanings to words, and how these meanings change in response to various experiences.”
How did each group of nineteen-month-olds perform? The researchers concluded that those with a family history of dyslexia had greater difficulty performing the new word-based tasks compared to those with no family history of dyslexia.
As this blog and the previous (Genetics of Dyslexia: Part 1) illustrate, whether we are peering into the brain via high-tech imaging or asking infants to learn new words using auditory and visual processing, the inherited nature of dyslexia is undeniable. This makes paying special attention to infants of families with known dyslexia a priority for the earliest possible diagnosis. Early detection of dyslexia can help dyslexic learners receive needed help before they fall too far behind.
The study this blog is based upon: https://onlinelibrary.wiley.com/doi/10.1002/dys.1649
October is Dyslexia Awareness Month! For a thorough discussion of dyslexia, you may enjoy the second edition of my award-winning book Raising a Child with Dyslexia: What Every Parent Needs to Know, available in softcover, hardcover, eBook, and audio. In addition to facts on testing and accommodation, my book gives you the tools to provide the social and emotional support children with dyslexia require. The second edition has the same great content as the first edition but now contains a very helpful bibliography and index and an exciting new cover.
You may also enjoy Failing Students or Failing Schools? A Parent’s Guide to Reading Instruction and Intervention, by reading specialist and shortlisted World Literacy Award nominee Faith Borkowsky.
Cardboard Box Adventures picture books are great for shared reading and can help parents establish a strong preliteracy foundation for their children. Check out the CBA Catalog for a full list of award-winning picture books, chapter books, and resources for parents and educators. Visit my Amazon author page for more information.