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Sunday, October 26, 2014

Brain Scans Map a Pathway to Reading and Dyslexia Diagnosis

From the Psychology Today Blog
"Raising Readers, Writers and Spellers"

By J. Richard Gentry, Ph.D.
October 9, 2014

Recent strides in brain imaging to map the pathway to reading and diagnose dyslexia are promising. (1, 2) Scientists are finding “a correlation between poor pre-reading skills in kindergarteners and the size of a brain structure (the arcuate fasciculus) that connects two language processing areas.” (3)

But are the brain and cognitive scientists who are conducting the research asking the wrong question?

Instead of scanning to discover how dyslexic brains in about 10 percent of the population are different shouldn’t they first be scanning to show the trajectory of 90 percent of children whose reading brains develop normally?

The normal trajectory is theoretically predictable through brain scanning as demonstrated below. Demonstrating the normal pathway should foster better beginning reading and writing instruction for all children in kindergarten and first grade, by scientifically providing markers or benchmarks for the minimal expectations on the pathway to reading at beginning, middle, and end of kindergarten and first grade as non-readers learn to read.

Dyslexia—a brain organization that is not optimal for reading—would likely pop up like sun spots once the normal brain scans for readers are clearly established.

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5 Developmental Phases are Easily Observed in the Path to Reading

Educational researchers have identified five developmental phases that are easily observed in beginning writing and in beginning word reading. (4, 5, 6) These phases follow a natural developmental progression in phonological awareness that can be measured with the same tests the brain scan scientists are using to show when children are aware of phonemes, when they segment them, when they identify them in isolation, and when they put them together in new ways to make new words.

In an activity called “phoneme blending” the dyslexia researchers found that children with lower awareness of how to blend sounds together to form a word had a smaller and less well organized arcuate fasciculus. This is theoretically predictable in the normal development of nonreaders who receive formal instruction in kindergarten and first grade as shown below:

Normal Phase Development of Beginning Writing

Look at the writing samples below which show a normal progression of how beginners move from no phonological awareness, to partial phonemic awareness (some letter-sound correspondence), to full letter-sound correspondences for all the sounds in each word, to spelling many words automatically and spelling unknown words in chunks of acceptable English spelling patterns. (7)

Phase 0 (Usually birth to age 3)


Phase 1 (Usually age 3 to 5*)
(Pictured in Phase 1 is a grocery list that says “milk, Raisin Bran, doughnuts.”)


Phase 2 (Usually age 3 to 6*)



Phase 3 (Usually age 4 to 6*)



Phase 4 (Usually age 4 to 7*)



* Age ranges depend on exposure to quality preschool
and/or literacy activity at home.

Normal Phase Development of Beginning Word Reading

The very same 5 Phases were independently discovered by a separate line of research in beginning word reading.8, 9 The word reading phases follow the same phonological development and exactly match the writing phases.

Phase 0 Word Readers:
  • Recognize a few words as wholes.
  • No phonological awareness for blending words.

Expected in preschool. (Example: a child recognizes name and environmental print such as the word STOP.)

Phase 1 Word Readers:
  • Memorize a few more words as wholes.
  • Child sees the word Crest and says “toothpaste;” the sign and the golden arches cue “McDonalds.”
  • No phonological awareness for blending words.

Expected by first half of kindergarten or sooner. (Children go through a phase where they recognize that words are made of letters but they don’t know that letters are pictures of sounds.)

Phase 2 Word Readers:
  • Continues to memorize sight words but also develops knowledge to cue on beginning and prominent letter/sound correspondences.
  • Child may see the word ink and say “ice.” The nonsense word klugmay be read as “king.”
  • Partial phonemic awareness for blending words. More words recognized on sight.

Expected by end of kindergarten or sooner.

Phase 3 Word Readers:
  • Many more words recognized automatically by sight.
  • Child distinguishes similarly spelled words such as king and kick.
  • The child begins to use known-word analogies such as pink to finger out ink.
  • Full phonological awareness for blending words is demonstrated with a letter for each sound.

Expected by first half of first grade or sooner.

Phase 4 Word Readers:
  • Generally one hundred plus words are recognized automatically.
  • The child not only cues on sounds for specific letters but also onc hunks of English spelling patterns. (The letter a may be a picture of /ā / and the chunk 'eigh' in eight is also a picture of /ā/.)
  • The child accurately decodes nonsense-word patterns such as yode, fler, clef, and recognizes syllable units in polysyllabic words such as man in human and command.
  • Phonological awareness for blending words in chunks of spelling patterns is evident.

Expected by end of first grade or sooner.

This normal development might account for the very same range of scores that the dyslexia scientists are reporting for arcuate fasciculus development between beginning kindergarten and end of first grade such as the progression of “Blending Word” scores from Blending Word 0, to Blending Word 3, to Blending Word 9, to Blending Word 11. (10)

The scientists should be able to detect dyslexia sooner by finding deviations from the normal trajectory in the expected benchmarks for beginning, middle, and end of kindergarten and beginning middle, and end of first grade. Importantly, by mapping the normal trajectory, scientists could demonstrate expected benchmarks for 90 percent of children who do not have dyslexia.

This post is a call for cognitive and brain scientists to construct the larger picture: fine tune the search for early detection and intervention for dyslexia by mapping the normal pathway to reading. Mapping the normal pathway would provide neurocognitive profiles as additional scientific support to foster benchmarking and appropriate instruction for the 90 percent of children in our schools who are not dyslexic, but whose kindergarten and first grade teachers may not be benchmarking or providing appropriate instruction simply because they have not been well trained to teach beginning reading and writing.

Sadly, I find a lot of kindergarten and first grade teachers who, through no fault of their own, have not been well prepared to teach beginning reading and writing. They march kids through a reading series, flounder with new standards, or teach reading, writing, spelling, and sounds as if they were unrelated skills. First year teachers with little preparation for teaching reading and writing are too often given assignments in poor performing schools.

Many beginning reading teachers do not know the minimally expected beginning, middle, and end of year benchmarks, or how to look at a child’s phase and target instruction.

This is especially egregious in poor schools in urban and rural communities where many children enter kindergarten with low language and vocabulary skills and little exposure to literacy, and where according to research children are less likely to have well-trained teachers.

As researchers follow children as they progress to second grade and evaluate whether a brain measure can predict poor reading skills it’s important to distinguish between children who are dyslexic and children with normal reading brains who have poor reading skills simply because they come to school unprepared and receive poor beginning reading instruction in kindergarten and first grade. Mapping the normal pathway will help scientists better distinguish normal readers from dyslexics and benefit both groups.

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For a superb review of diffusion imaging and biological development of reading circuits along with a call to apply neurobiological measures to individuals in order to understand reading pathways more broadly link here to Brian Wandell (Stanford) and Jason Yeatman’s (University of Washington) “Biological Development of Reading Circuits.”

For an excellent, concise description of the brain scanning research at MIT to help diagnose dyslexia click here. This article links you to an insightful interview with the authors. http://newsoffice.mit.edu/2013/brain-scans-may-help-diagnose-dyslexia-0813

References

[1] Lees, Kathleen (2014) Brain scans help detect early childhood reading problems. Science World Report (September 16, 2014)

http://www.scienceworldreport.com/articles/17205/20140916/brain-scans-help-detect-early-childhood-reading-problems.htm

[2] B.A.Wandell and J.D.Yeatman (2013). Current Opinions in Neurobiology. Vol 23, Issue 2, April 2013, Pages 261–268

[3] Trafton, Anne (2013) Brain scans may help diagnose dyslexia. MIT News Office (August 13, 2013) http://newsoffice.mit.edu/2013/brain-scans-may-help-diagnose-dyslexia-0813

[4] Ehri, L. (1995). Phases of development in learning to read words by sight. Journal of Research in Reading, 18, 116–125.

[5] Ehri, L. (1997). Learning to read and learning to spell are one and the same, almost. In C. Perfetti, L. Rieben, & M. Fayol (Eds.), Learning to spell: Research, theory and practice across languages (pp. 237–269). Mahwah, NJ: Erlbaum.

[6] Gentry, J. R. (2010) Raising Confident Readers: How to Teach Your Child to Read and Write—From Baby to Age 7. Cambridge, MA: Da Capo Lifelong Books.

[7] Gentry, J. R. (2010) Raising Confident Readers: How to Teach Your Child to Read and Write—From Baby to Age 7. Cambridge, MA: Da Capo Lifelong Books.

[8] Ehri, L. (1997). Learning to read and learning to spell are one and the same, almost. In C. Perfetti, L. Rieben, & M. Fayol (Eds.), Learning to spell: Research, theory and practice across languages (pp. 237–269). Mahwah, NJ: Erlbaum.

[9] Gentry, J. R. (2010) Raising Confident Readers: How to Teach Your Child to Read and Write—From Baby to Age 7. Cambridge, MA: Da Capo Lifelong Books.

[10] Trafton, Anne (2013) Brain scans may help diagnose dyslexia. MIT News Office (August 13, 2013) http://newsoffice.mit.edu/2013/brain-scans-may-help-diagnose-dyslexia-0813

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Dr. J. Richard Gentry is the author of Raising Confident Readers: How to Teach Your Child to Read and Write–From Baby to Age 7. Follow him on Facebook, Twitter, and LinkedIn and find out more information about his work on his website.

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