Tuesday, February 6, 2018

What is Dyslexia and Dysgraphia? Neuroscience Explores the Answers...

CAUTION: This blog provides an in-depth explanation of the research surrounding dyslexia and dysgraphia! Proceed at your own risk...

There are a few researchers I follow closely in an effort to keep abreast of the ever-growing definition of Dyslexia and Dysgraphia. Technology is changing the way we think about these two areas of reading and writing struggle. With the advent of the fMRI (Functional MRI) in the 1990s, neuroscience is providing insight we never had before, helping to shape our understanding of diagnosis and intervention.

The greatest take-away from the research is this: dyslexia is primarily a language disorder rather than a visual disorder; dysgraphia is primarily a language disorder more than a fine motor weakness. Knowing this helps us understand that we need to approach reading and writing from a language perspective, rather than with vision therapy and occupational therapy alone--although those therapies may be required in some cases for kids who also have visual or fine motor impairments. This information is relatively new, and is therefore not widely understood.

In many public schools, Speech-Language Pathologists can not work on reading and writing and many intervention specialists are not trained in dyslexia interventions. Thus, parents need to fill the gap, providing appropriate treatment, either by educating themselves, or by finding private tutors who understand dyslexia and dysgraphia.

One of my favorite researchers to follow is Virginia Berninger, PhD. Berninger coined the model I always quote:

In their book, Dyslexia, Dysgraphia, OWL LD and Dyscalculia: Lessons from Science and Teaching, Virginia Berninger and Beverly Wolf summarize the latest research and its indications for effective intervention. As I discuss their book, I will summarize a few salient points and cite important quotes for you.

To fully understand dyslexia and dysgraphia, we need to understand reading and writing. When focused on teaching reading and writing, it is easy to forget that all learning reflects the status of the developing brain. All language is cognitive, and all cognition is neurological. Therefore, we educators must acknowledge neuroscientists and their discoveries.

Neuroscience reveals that there are key regions within the left hemisphere that execute reading and writing. "Broca's area [located on the left side of the brain, near the front] has been shown to house executive functions for all language systems--listening, speaking, reading, and writing" (4). Wernicke's area (located in the left temporal lobe) is the region involved in language comprehension. "According to contemporary brain imaging research, structural and functional differences occur between typical readers and writers and individuals with specific learning disabilities (SLDs) in both Broca's and Wenicke's regions" (4).

In addition, scientists have determined the hereditary nature of dyslexia and dysgraphia, manifested in families with various severity levels and learning struggles. Two specific genes have been associated with dyslexia in replicated research studies.

So what does this mean?

"Collectively, these genetic findings have educational implications. Genes may influence learning in at least three ways:

"First, genes may affect how the brain is wired during early fetal development" (11). In a conference I attended in 2016, presented by Nadine Gaab from Harvard Medical School, Gaab supported Berninger and Wolf, noting that fetal differences are being observed in her research studies.

"Second, genes may affect maturation of the brain after birth by guiding the process of [myelination]"(11), which is the coating of axons needed to transmit signals with more speed and efficiency . In other words, myelination is needed for learning, and this process may be delayed or impaired. Nadine Gaab described this as a weakness in white matter, which acts to communicate between key language regions. White matter is "the information highway" from the front to the back of the brain. Gaab gave the metaphor that weakness in white matter results in an information highway that is less robust and often bumpy.

Third, as stated above, "genes may contribute to two core types of impairments typically found in children with dyslexia: phonological and executive function" (11).

Another key area of the brain involved in reading and writing is a region in the back of the brain responsible for word-form memory. This region is "where spoken and written words are coded into memory for further processing . . . Children with and without dyslexia differ not only in phonological coding . . . but also in orthographic coding" (11). In other words, children with dyslexia have weakness in both phonological processing (managing sound) for reading, but also in developing the sound-to-symbol relationship needed for writing, and the word-form memory needed for reading fluency, writing fluency, and spelling. 

One final thought, as this is a lot to take in: There is research supporting the efficacy of multisensory intervention strategies for improving reading and writing, demonstrating that phonics practice is not enough. Reading and writing intervention needs to include phonological processing practice, orthographic (writing) practice, and morphological (word study) practice.

These combined interventions result in "chemical activation in the brain" in the key regions of weakness (12).

You may have noticed that this summary of recent research was only the most salient points through page 12 of Berninger & Wolf's book. Whew! Dyslexia and dysgraphia are complex problems requiring complex intervention. This is why we break our classes into four parts: Phonics & Spelling (where we show you how we support phonological processing), Vocabulary & Word Study (where we demonstrate strategies to improve morphological knowledge), Grammar & Punctuation (where we help kids connect to other language regions on the information highway), and Supported Writing & Editing (where we demonstrate kind and gentle orthographic training).

This is also why, in our Roots Entwined classes, we passionately promote a learning process we call Intentional Copywork and Dictation, in which phonics, spelling, word study, grammar, and comprehension are all taught in mini-lessons, then practiced in writing, week after week. This practice includes all the individual skills of reading/writing (mini lessons) and then works on consolidating them all together (copywork and dictation), which makes for intentional learning.

At Rooted in Language, we believe what the research supports: Strengthening all key areas of weakness, through skill training and consolidation practice (as described above) in reading and writing, is the very best way to help struggling learners progress.

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