Post on 25-Mar-2020
David P. Hurford, Ph.D.Center for Research, Evaluation and Awareness of Dyslexia
Center for READing Pittsburg State University
What do School Counselors Need to Know About Dyslexia?
Characteristics of Dyslexia
• Specific Learning Difference that is neurobiological in origin
• Difficulties with accurate and/or fluent word recognition
• Poor spelling and decoding abilities
• Result from a deficit in the phonological component of language that is often unexpected in relation to other cognitive abilities
• Dyslexia can occur even with effective classroom instruction Secondary consequences may include problems in comprehension
• Reduced reading experience that can impede the growth of vocabulary and background knowledge.
Demographic Characteristics of Children with Dyslexia
• Affects at least 20% of our Nation’s Children• 50% do not Graduate from High School• At Risk for Parental Abuse• More Likely to:
• Have Poor Self-Esteem• Anxiety and Depression• Suicidal Ideation• Substance Abuse• Be involved in the Juvenile Court System• Be involved in the Criminal Court System as Adults• May need Public Assistance
Social as well as Academic Difficulty!
Successful Individuals with Dyslexia
• Dr. Helen Taussig (founded the field of pediatric cardiology)
• Steven Spielberg
• Bella Thorne (actress, singer, model & dancer)
• Henry Winkler
• Jennifer Aniston
• Dav Pilkey (author of Captain Underpants)
• Cher
• Jack Horner (most famous paleontologist)
Common Myths
• Dyslexia affects boys more than girls• Dyslexia is a visual difficulty
• Letter reversing• Individuals who are intelligent do not have dyslexia• People with dyslexia cannot read• Dyslexia will be outgrown• If individuals with dyslexia would try harder, they
would not have dyslexia• Einstein had dyslexia
Speech DevelopmentListening to speech results in similar activation in both adults who are very familiar with their language and two-month-olds who are not.
Dehaene-Lambertz, Dehaene & Hertz-Pannier, Science 2002Dehaene-Lambertz et al., PNAS 2006, Neuron 2015
Speech Developmento Development of phonological processing
o Speech development is natural
o Acoustic Signal is continuous/words are categorical
o Reading development is not
“I like to read.”
Reading Developmento The process of learning to read.
o Begins with speech development
o Phonological processing
o Letter-Sound
o Decoding
o Synthesizing
o Spelling
o Comprehension
Etiology of Reading Difficulties:Phonological Processing Deficits
o Neurological in origin
oNeurodiversity!
o Genetics plays a role
Hypothetical Reading Achievement Mathew Effects (Stanovich)
0
100,000
200,000
300,000
400,000
500,000
600,000
700,000
800,000
900,000
1,000,000
Poor Average
Reading Group
Number of Words Read per Year
Nagy and A
nderson (1984)
0
1000000
2000000
3000000
4000000
5000000
6000000
7000000
8000000
9000000
10000000
Poor Avereage Voracious
Reader Group
Number of Words Read per Year
Mathew Effects (Stanovich)
Attention Deficit Hyperactivity Disorder
Why Assess for ADHD?• Why assess ADHD for children who might have
reading difficulties?
• Thirty percent (30%) to 50% of children who have reading disabilities/dyslexia also have ADHD.
• Nearly all children who have ADHD will have difficulties learning to read
Definition of ADHD
o Refers to Attention Deficit Hyperactivity Disorder
o ADHD is a neurobiologically-based diagnosis applied to children and adults who consistently display certain characteristic behaviors over a period of time.
o The most common core features include:
o Distractibility: poor sustained attention to tasks
o Impulsivity: impaired impulse control and delay of gratification
o Hyperactivity: excessive activity and physical restlessness
Genetic Components of Dyslexia
Genes related to Dyslexia
Locus/Gene LocationDYX1 15q21DYX2 6p22DYX3 2p16‐15DYX4 6q13‐16DYX5 3p12‐q12DYX6 18p11DYX7 11p15DYX8 1p34‐36DYX9 Xq27
DCDC2
o DCDC2 plays an important role in the development of dyslexia (DYX2).
o DCDC2 contains SNPs and a deletion potentially connected to dyslexia.
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How DCDC2 Works
Radial Glia
4 days
Neuronal Progenitor
developing gray matter (cortex)
developing white matter (projection tracts)
stem / progenitor cell reservoir in fetal brain (subventricular zone)
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DCDC2 SNP Removed In Mice
Giraud, A. L., & Ramus, F. (2013). Neurogenetics and auditory processing in developmental dyslexia. Current Opinion in Neurobiology, 23, 37-42.
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Neurological Correlates of Dyslexia
Simplistic Depiction of Brain Initial Reading Process
Simplistic Depiction of Brain Brain is complicated!
o Although the brain is lateralized for certain functions, information is processed by neural circuits that cross hemispheres.
o Information is shared between hemispheres.
o Each is likely responsible for different bits of processing
o Specific locations responsible for aspects of reading are interconnected with many other brain areas.
Axonal Connectionso What reading is really like!
www.humanconnectomeproject.org/
Early IdentificationWhy is early identification important?
Reading Acquisition• Linking graphemes with phonemes is difficult
and takes a tremendous amount of effort• This must be explicitly taught• Teachers must initially focus on the “yellow”
route• As reading become automated, the reader moves from
graphemes to meaning• The “green” route develops
from practice and effort
Stanislas Dehaene, 2017
Visual Word Form AreaEvidence that left fusiform gyrus (VWFA):
• Reorganizes as a function of reading
• Some neurons are not dedicated to specific processing tasks for some time
• At some point, those neurons that could be processing letters and words are released to engage in facial recognition.
Visual Word Form Area (VWFA)
• Development of reading skills in the VWFA
Stanislas Dehaene, 2017
Remediation Effects (Initial Reading)
Individuals without Dyslexia
Individuals with DyslexiaPre Post
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Why is Learning to Read so Difficult?
Writing Systems
Writing SystemsAlphabetic Principle
• Understanding that letters represent speech sounds
• Understanding that there is a predictable relationship between these letters and sounds/phonemes
• This knowledge is critical to reading acquisition
Transparent Writing Systems
• There is a one-to-one relationship between the letters and the sounds that they represent
• Each letter represents ONLY one sound• Each sound is represented by ONLY one letter• Examples: Spanish, German, Scandinavian
Languages, etc.• Children learning to read transparent writing
systems:• Begin later than children learning to read English• Are finished sooner
Opaque Writing Systems
• There may not be a consistent one-to-one relationship between the letters and the sounds that they represent
• There are approximately 44 phonemes in English
• Only 26 letters
• Some letters, therefore, represent several sounds
The Problem RevisitedOpaque Writing Systems• One sound might be represented by several different
letters (spellings):• For example:
• /ē/ sound:
• /k/: “c,” “k,” “ck, ” “ch” and “qu”• /g/: “g” and “j”
“e (meter)” “ee (street)” “ea (heat)”
“e-e (athlete)” “y (silly)” “ie (believe)”
“ei (receive)” “ey (money)” “i (piano)”
The Problem RevisitedOpaque Writing Systems
• Some phonemes are represented by two letters (digraphs):
• For example:
“sh” Voiced “th” Voiceless “th”
“ow” “au” “aw”
“oi” “oy” “ch”
“ng” “zh” “oo”
“hw”
The Problem Revisited
• Opaque Writing Systems
• R-Controlled vowel digraphs:• For example:
“ar (car)” “ar (care)” “or (author)”
“er (her)” “ir (fir)” “ur (turn)”
Writing Systems• Opaque Writing Systems• Once all of the letter-sound correspondences have
been acquired:• Then there is the issue of alternative spellings• French, German, Latin, Greek, and Danish
contributed to English• The English writing system retained the spelling
systems of these languages
• As a result, there can be several spellings for homophonic words:
• e.g., “two,” “too” and “to;” “threw and through,” etc.
Questions?
www.pittstate.edu/READing
www.facebook.com/Center.for.READing
For More Information
David P. Hurford, Ph.D.Center for READing
Pittsburg State University
dphurford@pittstate.edu