The Neuropsychology of Reading Disorders:
Diagnosis and Intervention
Primary Presenter:
Steven G. Feifer, D.Ed., NCSP
School Psychologist
Frederick County Public Schools
Email: Feifer@FrederickMd.com
Presentation Goals:
1. Discuss the pitfalls of relying an IQ/Achievement discrepancy model as
the sole basis for identifying reading disorders in young children.
2. Link brain functions to the reading process and introduce a brain-based
educational model to effectively identify and classify subtypes of
reading disorders.
3. Discuss the various subtypes of reading disabilities from a
neurobehavioral point of view, and tie in appropriate educational
strategies for each subtype.
4. Introduce the 90 minute dyslexia evaluation as a more comprehensive
means to evaluate reading disorders in children and provide
educators with more meaningful information to craft appropriate
intervention techniques.
*Copyright c 2000 by School Neuropsych Press, LLC
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10 Pitfalls of Aptitude/Achievement Discrepancies
1. There is no universal agreement on what the discrepancy should be.
2. It remains unclear as to which IQ score should be used to establish a
discrepancy.
3. A discrepancy model of reading disabilities precludes early identification.
4. Intelligence is more a predictor of school success, and not necessarily a
predictor of successful reading.
5. There is little evidence to suggest that poor readers on the lower end of the
reading distribution differ from individuals classified as dyslexic.
6. It is illogical to utilize just one method to calculate a learning disability
when research from the neuropsychological literature has documented
numerous subtypes of reading disabilities.
7. Discrepancy models are not developmentally sensitive toward different stages
of reading at different age groups.
8. A discrepancy model promotes a wait and fail policy forcing intervention to
come after the fact.
9. Discrepancy formulas often do not detect subtle neurological variations such as
organization and attention problems, poor memory and retrieval skills, and
dyspraxias and dysphasias. In other words, they are too simplistic.
10. It's often used as a political means to regulate funding for special education.
Developmental Dyslexia: The term refers to an inability to acquire functional reading
skills despite the presence of normal intelligence and exposure to adequate
educational opportunities. This term is often synonymous with the term
"learning disabled", and assumed to represent 5 to 10 percent of all school-aged
children.
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ALTERNATIVE ASSESSMENT METHODOLOGIES
Reauthorization of IDEA:
* President Bush signed the IDEA bill into law in December, 2004.
* States may opt out of using a discrepancy model to identify learning
disabilities, and replace by using a Response-to-Intervention model.
* Gives school districts flexibility to craft a policy whereby students who
do not respond to scientifically-based early reading programs may
be considered eligible for special education services.
* Requires districts with significant over-identification of minority
students to consider eliminating IQ testing and establish
procedures to reduce disproportional representation in special ed.
RESPONSE TO INTERVENTION MODEL
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ALTERNATIVE ASSESSMENT METHODOLOGIES
Curriculum-Based Measurement – an assessment of reading fluency by selecting a
random probe is from the student’s basal reader, and the median number of words read
correctly in one minute is recorded. Multiple measures in 3-minute intervals are
administered throughout the year, instead of relying upon lengthy standardized tests.
Advantages: * Better ecological validity than norm referenced testing.
* Quicker and cheaper than norm referenced testing.
* Allows for earlier intervention opportunities.
* Emphasis on discrepancy from peer performance, not IQ.
* Evaluation hi-lights reading, not bureaucratic categories
* Linked to a problem solving model. (Shinn, 2002)
Disadvantages: * Not a diagnostic approach.
* Does not assess many other aspects of reading such as
comprehension.
* Does not answer the most important question: Why?
NEUROPSYCHOLOGY: A BRAIN/BEHAVIORAL
APPROACH
Neuropsychology: A hybrid utilizing both a medical and psychological model of
human functioning which examines brain/behavior relationships. The
underlying assumption is that the brain is the seat of all behavior; therefore
knowledge of cerebral organization should be the key to unlocking the
mystery behind most cognitive tasks.
Evolution of Reading: * Encompassed just the past 5000 to 6000 years
* Approximately 1/3rd of world's population illiterate
* Human beings seem pre-wired to acquire sound/symbol
language code.
* Some estimates suggest 75% of children will learn to read
in spite of methodology (Mather, 1992).
* 20 % of children need a specific method (ie reading recovery)
* 5 % may never acquire this skill at a functional level
Brain:
* Weighs approximately 1400 grams ( 3 pounds)
* 100 billion cells comprised of neurons (gray matter) and glial cells
(white matter)
* Each neuron makes contact with as many as 10,000 other neurons.
* The firing rate of a neuron ranges from a few to several hundred per
second.
* Makes up less than 2 percent of body weight, though uses up 25 percent
of oxygen supply and 70 percent of glucose.
* DNA evidence suggests human brain has been evolving for
approximately 5 million years.
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GENERAL BRAIN STRUCTURES
a) Hemispheres - nearly 99 percent of right-handers and 67 percent of left handers of
language housed in left hemisphere. Cerebral dominance usually refers to just language
functions.
Gender Differences: Both hemispheres are not symmetrical, though more asymmetry
noted in males and females. Thus, cortical functions tend to be more lateralized in males
than females. For instance, in males, reading centers located primarily in left
hemisphere, leaving little "back up" if damage occurs to this area. In females, reading
centers may be housed in both hemispheres, leaving a "back up" function if there is
cortical damage (Goldberg, 1981). Explains why only male stroke patients often lose
speech, and perhaps why more boys than girls in special education.
Right hemisphere - dependent upon more white matter than gray matter, and tends to
respond best to novel stimuli. Can comprehend language (mainly nouns) though
cannot generate speech, spell, or decode non-words (Ogden, 1996).
Left hemisphere - dependent upon more gray matter, and tends to be geared toward
over-learned tasks. Possesses a phonological route to reading and can read nonwords.
b) Neocortex:
Frontal Lobes - organizes and arranges information leaving the brain.
Parietal Lobes - responsible for sensory and motor functions.
Temporal Lobes – houses acoustically based information and language
Occipital Lobes - visual processing centers of the brain.
c) Fiber Tracts: 1. Projection Fibers - involved in subcortical connections
from lower brain regions, such as thalamus, to the neocortex.
2. Association Fibers - consist of both long and short fiber
bundles that connect cortical areas to one another.
3. Commissural Fibers - primarily function to connect the
two cerebral hemispheres. The largest of these fibers is the
corpus callosum, a band of approximately 200 million
nerve fibers which connect each hemisphere.
d) Nuclei: Consist of bundles of nerve cells with a common function. For
instance, the thalamus serves as a relay center in the brain to
process all sensory input except for smell.
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4 KEY BRAIN CONCEPTS WITH RESPECT TO READING
(1) At birth, the human brain weighs just 25% of its adult weight, thereby
leaving more room for the environment to shape brain growth more than any
other species (Chase, 1996).
Environmental Learning: (Kotulak, 1997)
* Average number of words spoken daily in a professional household……1500 -2500
3.5 million words by age three
* Average number of words spoken daily in a middle class household …..1000 - 1500
2.0 million words by age three
* Average number of words spoken daily in welfare household…………. 500 -800
1.0 million words by age three
* Furthermore, children in welfare families hear negative remarks twice as often as
positive ones (Kotulak, 1997).
* Human brain volume 95 % of its adult weight by age 5 (Stahl, 2000).
Adapted from Shaywitz (2004).
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4 KEY BRAIN CONCEPTS WITH RESPECT TO READING
(2) Prenatal factors have been linked to brain development, as proteins are
crucial in forming latticework of synaptic connections between brain cells.
Fast Facts: * More synapses present in brain by age 6 than any other time (Stahl,2000).
* 83 percent of dendritic sprouting occurs after birth (Berninger et al, 2002)
* Glial cells guide the migration process by making tracks and pathways to
which neurons attach. Ectopias represent misplaced clusters of neurons
that may be related to prenatal alcohol and nicotine consumption.
* Unlike cells in the PNS, cells in CNS generally do not regenerate (?).
STAGES OF BRAIN DEVELOPMENT:
I. Proliferation - cells proliferate and divide in the developing fetus from
an inside to outside fashion. The cortex overproduces neurons,
maximum growth complete before birth – maybe 1 trillion formed.
II. Migration - cells migrate to appropriate location in the brain.
a) Aggregation - cells cluster into nuclei, like thalamus.
b) Arborization - thickening of dendrites as cells
interconnect.
III. Differentiation - First 2 or 3 years post-natally, neurons continue to
subdivide forming an overabundance of synapses. This
overproduction appears to help children recover from brain
damage more easily than adults (plasticity).
Pruning - many more cells are produced than are needed. For maximum efficiency on a
task, cell death is essential. Neuronal death and the re-organization of axondendritic connections occurs during the first few years. Perhaps 50 to 90%
eventually die (apoptosis) leaving the mature brain with 100 billion neurons.
Auditory Pruning - every child is born with the ability to discriminate all sounds.
However, based upon exposure to cultural specific dialects, a child
becomes tuned to only sounds from host language. Explains why
children born in another country continue to have foreign accents if
brought to the United States past age five.
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4 KEY BRAIN CONCEPTS WITH RESPECT TO READING
(3) Wiesel and Hubel won the Nobel Prize for two landmark discoveries about
the brain. (1) Sensory experience remains essential for teaching brain cells their
jobs. (2) After a certain critical period, brain cells lose the opportunity to learn
these jobs and seek out other duties to perform.
SUMMARY: There are certain windows of opportunity for learning based upon the
developing nervous system, brain growth spurts, and subsequent myelination. Sensory
experiences are essential for teaching brain cells their jobs, and after a certain critical
period, brain cells lose their opportunity to learn their jobs (Kotulak, 1997). For instance:
Vision: * If a child does not process visual experiences by age two, the sense of
sight will never develop properly.
Hearing: * If a child does not hear words by age 10, they will have significant
difficulty learning a language.
(4) Educators must synchronize instructional strategies with specific neurodevelopmental windows to determine the most opportune time to offer a reading
intervention.
THE TIMING OF LEARNING
AGE
SKILL
BRAIN REGION
3 -10 months
Attention &
Awareness
Language
Acquisition
Phonemic
Development
Reticular Formation
10 - 12 years
Abstract
Language
Inferior Parietal Lobes
and Frontal Lobes
14 - 16 years
Judgement &
Planning
Frontal Lobes
2 - 4 years
6 - 8 years
Temporal Lobes
Inferior Parietal
and Temporal Lobes
* Increment in brain weight 5-10 percent over each 2 year period.
* Expansion not due to neuronal proliferation, but rather growth in
dendritic processes and myelination.
DEVELOPMENTAL READING MILESTONES:
RED FLAGS FOR DYSLEXIA
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Preschool Years: *
*
*
*
*
Trouble learning nursery rhymes.
Speech and language delays.
Inability to distinguish rhymes.
Frequent ear infections.
Failure to recognize letters in name.
Kindergarten & 1st Grade:
* Inability to generate rhyming words.
* Inability to associate letters with sounds.
* Inability to segment words by syllables.
* Difficulty pulling apart words by segments such as “horseshoe”
can be divided up into “horse” and “shoe”.
* Difficulty recognizing the order of sounds in words. For
instance, “say the word tiger without the g sound”.
* Difficulty reading common one-syllable sight words.
* Frustration in school and complaints about reading.
2nd & 3rd Grades:
* Failure to read at least 40 words per minute.
* Slow progress in acquiring basic reading skills, and working
at least one grade below level.
* Inability to master basic functional sight words such as “that,
is, the, has, etc.”
* Over-reliance on context to derive meaning from print.
* Slower paced and effortful reading.
* Spelling skills which are not phonetically consistent.
* Fear of reading aloud in class.
* Stumbling on multi-syllable words and phonetically irregular
words.
* Oral reading lacks inflection and tendency to read through
punctuation.
* Word retrieval difficulties in class discussions.
* Family history of reading difficulties.
Secondary Grades:
*
*
*
*
*
*
*
Inability to read at least 60 words per minute.
Poor fluency skills.
Unusually long hours spent doing homework.
Disinclination to read for pleasure.
Fatigue quickly when reading.
Mathematics a demonstrative strength.
Tendency to substitute words when confronted with unfamiliar
words in the text.
* Extreme spelling difficulties.
Adapted from Shaywitz, (2003).
HIGHER CORTICAL FUNCTIONING
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Frontal Lobe
Parietal Lobe
Temporal
Lobe
Occipital
Lobe
Occipital Lobes - forms the posterior pole of the brain and processes visual input.
.
* Neurons most affected by environment as early deprivation leads to
fewer synapses.
(Ventral Stream) * Deficits resulting in visual recognition and visual naming reflect
occipital/temporal junctions of left hemisphere (visual agnosia)
and often co-occur with reading difficulties.
(Dorsal Stream) * Deficits in determining where an object is in space reflect
occipital/parietal junctions and result in difficulty with letter
and number recognition as well as reading maps and clocks.
* Also, skilled over-learned movements (handwriting) a function of
occipital/parietal functions (angular gyrus) (Goldberg, 1989).
Temporal Lobes - Very involved in processing language and acoustical information.
Most phonological discrimination tasks primarily take place in the
superior temporal gyrus (plana temporale). This region is critical for
decoding the 44 phonemes which comprise the English language.
* There is marked asymmetry in the structure of the temporal lobes,
with the left being larger than the right.
* Damage to Wernicke's area impairs receptive language functioning.
* Acoustic agnosia - inability to give meaning to nonlanguage sounds.
* Very much involved in memory functioning, retrieval of words,
auditory perception, and mood stability due to the many projection
fibers leading to limbic system.
* Right temporal lobes involved with recognizing faces, interpreting
music, rhythm and pitch, and prosody of speech.
* Mediates visual/verbal learning.
HIGHER CORTICAL FUNCTIONING
Parietal Lobes - involved in sensory and tactile functioning as well as visual spatial
Neuropsychology of Reading Disorders
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orientation. The posterior portion of the inferior parietal lobe
represents the interface of occipital, temporal, and parietal lobe
junctions. This is where many higher order or tertiary functions
take place and theoretically the seat of higher level intelligence.
* Damage to left parietal lobe can lead to dyslexia, dysgraphia, and
dyscalculia, whereas damage to the right can lead to deficits
in visual spatial skills and constructional dyspraxia.
* Angular gyrus - interface between occipital and parietal lobes with
deficits involving the visual spatial appreciation of words.
* Insular cortex - buried deep in the folds between parietal and temporal
lobes. Some research has suggested involvement in automatizing
the reading process (Paulesu, Frith, Snowling, Gallagher, Morton,
Frackowiak, & Frith, 1996)
Frontal Lobes - the band conductor of the brain. Organizes and arranges information
leaving the brain. Involved in planning, judgement, impulse
control, cognitive flexibility, and executive functions. Last region
of the brain to become fully myelinated.
* Represents 30 percent of the neocortex.
* Broca's Area - responsible for the production of language. PET scans
have linked Broca's area to performance on rhyming tasks.
Involved in the neurocircuitry of reading.
* Prefrontal Cortex - involved in shifting attention, a pre-requisite for
reading comprehension.
NEUROIMAGING STUDIES OF DYSLEXIA
(Posner & Raichle, 1994)
(1) Reading is clearly a left-hemispheric task..
(2) PET scans demonstrate the capacity of the brain to change areas being used as a
result of instructional strategies.
(3) Well known visual words are not recorded in Wernicke’s area (superior temporal
gyrus). PET scans reveal this area is quiet and increased activation in insular
cortex.
(4) Insular Cortex - buried deep in the folds between in the posterior portion of the brain
and may be responsible for the automaticity of reading (Paulesu, et al, 1996)
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NEUROIMAGING STUDIES OF DYSLEXIA
Shaywitz (2003)
* Nonimpaired readers activate primarily posterior portions of left hemisphere.
* Impaired readers under-activate posterior regions and activate primarily frontal
areas.
THE NEURAL CIRCUITRY OF DYSLEXIA
Phonological Circuit: (Advanced readers skip steps #2 and #3)
Step 1 - the English language is read from left to right. Visual information
projected to extrastriate cortex in right occipital lobe.
Step 2 - Information travels via the corpus callosum to left temporal lobe
for phonemic coding (Grapheme/Phoneme analysis)
Step 3 - Auditory cues used to decipher word from lexicon by way of angular
gyrus and supramarginal gyrus.
Step 4 - Insular cortex automatizes process to allow for rapid and automatic word
recognition. Information then sent to frontal lobes for output.
Step 5 - Whole word recognition travels to Broca's area by way of arcuate
fasciculus. This completes the articulatory loop and word is read
aloud.
3-HEADED MONSTER OF READING
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FLUENCY
COMPREHENSION
DECODING
CHARACTERISTICS OF READING DISABLED CHILDREN:
* Poor decoding skills
* Weak vocabulary development
* Inability to read strategically
* Poor spelling
* Few reading opportunities outside of school
* Poor motivation and confidence
3 WAYS TO IDENTIFY WORDS IN PRINT:
1. Phonological Code - using sound patterns to identify words.
2. Orthographic Code - using visual contour and shapes to identify words
3. Semantic Code- using meaning of text to identify words.
SUBTYPES OF DYSLEXIA
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1. Phonological Subtype - Great difficulty using phonological route in
reading, so visual route to lexicon used. There is little reliance
on letter to letter sound conversion. Instead, an over-reliance
on visual cues to determine meaning from print.
Neuropsychological significance: Left superior temporal gyrus.
Assessment:
Language delays
Difficulty with rapid naming
Trouble detecting rhyming words
History of reading difficulties in family
Inaccurate oral reading
Difficulty decoding nonwords
Dysphonetic spelling
Structural Explanations:
(1) The most compelling evidence that actual structural formations of the dyslexic brain
inhibits phonological processing stems from Geschwind & Galaburda (1985). Deviations
of the plana temporale or superior surface of the temporal lobe may explain deviations
in reading performance.
(2) Asymmetry of the plana temporale is visible already at 31 weeks of fetal age
(Galaburda, Rosen, & Sherman, 1990). Hynd, Marshall, & Clikeman (1991) also
concurred that deviations in the development in the cortex generally occur between the fifth
and seventh month in fetal development, with neuronal abnormalities noted in the left
temporal and bilateral frontal lobes. According to Hynd et al (1991), there is a big spurt in
brain weight between the 24th and 26th prenatal week. This is characterized by the
development of the various gyri and sulci of the brain, and once this general pattern is laid
out, it remains fairly constant. Thus, deviations in the plana temporale are visible at this
time, perhaps derived from neural ectopias, lending credence to the possibility of actually
detecting a learning disability prenatally.
(3) Tallal, Miller & Fitch (1993) attributed phonological deficits to difficulty detecting
rapidly changing acoustic elements of speech. Thus, subtle auditory perceptual deficits,
such as differentiating between a “ba” sound and a “da” sound may be the underlying
deficit in phonological dyslexia. Basic premise behind Fast Forward technique.
PHONOLOGIAL DYSLEXIA INTERVENTIONS
Error Analysis:
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Same sound/Different spelling
aye
buy
by
die
hi
thai
height
guide
Irregular Words
listen
debt
know
psychology
right
sword
bomb
clue
Under Age 7:
Fast Forword (Tallal)
Earobics I
Phono-Graphix
Lindamood Phoneme Sequencing
Program (LIPS)
Ages 7 - 12:
Alphabetic Phonics (OrtonGillingham)
Slingerland
VAKT
LIPS
Project Read
Synthetic Phonics Approach
Over Age 12:
Wilson Reading System
SRA Corrective Reading
SURFACE DYSLEXIA
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2. Surface Dyslexia - sometimes referred to as visual form dyslexia or dyseidetic
dyslexia as characterized by an inability to visualize words in a fashion where the process
of reading becomes automatic. These children tend to over-rely on sound/symbol
relationships as the process of reading never becomes automatic. Words are
painstakingly broken down to individual phonemes and read very slowly and laboriously,
especially where phonemes and graphemes are not in a 1 to 1 correspondence.
Neuropsychological significance: Occipital/parietal junctures of angular gyrus, role of
insular cortex, and corpus callosum deficiencies.
Assessment Techniques:
Jordan Left Right Reversal Test
SB5 (Visual-Spatial Processing)
Beery Visual Motor Integration Test
NEPSY (arrows)
WISC IV (Block Design, Matrix Reasoning)
RIAS (NIX Index)
WJ III (Spatial Relations, Visual Closure)
Structural Explanations:
(1) Goldberg (1989) reasoned that some reading and writing deficits may occur
due to the disintegration of visual and spatial representations in our brains. Areas
of the occipital lobe (processing vision) and the parietal lobe (processing spatial
awareness) intersect in the inferior parietal region known as the angular gyrus
(interface of occipital and parietal lobes). In the left hemisphere, this region of our
brain allows for the visual-spatial appreciation of linguistic information.
(2) Insular Cortex - buried deep in the folds between parietal and temporal
lobes. PET studies have suggested involvement in automatizing
the reading process (Paulesu, et. al, 1996)
(3) Multiple Pathway Model (Shaywitz, 2003) - there are multiple pathways in
the brain which modulate various aspects of the reading process. These consist of
two relatively slow pathways which dyslexic readers over-rely upon, and one
quicker pathway used by normal readers.
(a) Broca’s Area (Inferior frontal gyrus) reads by slowly sounding out words.
The end point of the inner articulation system.
(b) Parietal-Temporal (Supramarginal gyrus) region slowly pulls words apart by
analyzing the spatial arrangement of sounds. Crucial in spelling process.
(c) Occipital-Temporal region automatically recognizes word forms. Dyslexics
tend to under-activate this region.
SURFACE DYSLEXIA INTERVENTIONS
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(4)
Magnocellular pathway deficits have been linked to speed of temporal
lobe processing (Demb, Boynton, & Heeger 1997). Research suggests
that lack of visual motion discrimination, not poor temporal lobe
processing at theroute of dyslexia. .
* Some studies have linked deficits in this circuitry affects up to 75 percent
of dyslexics (Ridder, Borting, Coope, McNeel, & Huang, 1997)
* Abnormally small cells presumed to slow processing speed from retinal
ganglion cells projected to lateral geniculate nucleus of thalamus.
This in turn slows processing to primary visual cortex. Therefore,
slower reading due to limited processing by visual cortex (Demb, 1997).
* Hypothesis not well supported in literature. Most agree that reading is a
phonological and linguistic deficit, not a visual one.
Error analysis of Surface Dyslexia:
Word
island ………………………
grind ……………………….
listen ………………………
begin ………………………
lace ………………………..
Remediation Techniques:
Read as:
izland
grinned
liston
beggin
lake
Under Age 7: Analytic or Embedded Phonics Approach
("top down" methodology)
Distar
Reading Recovery
Ages 7 - 12:
Great Leaps program
Neurological Impress method
Over Age 12:…. Neurological Impress method
Wilson Reading System
Laubach Reading Series
MIXED DYSLEXIA
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3. Mixed Dyslexia - severely impaired readers with characteristics of both
phonological deficits as well as visual/spatial deficits. These readers have
no usable key to the reading and spelling code. Very bizarre error patterns
observed.
Error Analysis of Mixed Dyslexics:
Word
Read as:
advice
exvices
correct
corexs
violin
vilen
museum
musune
possession
persessive
material
mitear
Structural Explanations:
(1) The corpus callosum consists of a band of approximately 200 million nerve
fibers connecting the two hemispheres of the brain. Some studies (Hynd, Hall,
Novey, Eliopulos, Black, Gonzalez, & Edmonds, Riccio, & Cohen, 1995) have
suggested that the genu of the corpus callosum is much smaller in dyslexic
individuals.
(2) According to Bakker (1992), reading and spelling are most strongly associated
with right-hemisphere activity during the first two years of initial reading.
However, there is a rapid shift toward left-hemisphere activity after that initial
phase. Therefore, orthographic codes allow beginning readers to detect key
features in words: however, by the end of 1st grade there is a hemispheric shift of
reading mediated primarily by the left hemisphere. Mixed dyslexia may reflect
deficits in the ability of the brain to shift modes of operation.
(3) Human information processing occurs on the order of milliseconds, and is
greatly dependent upon multiple neural networks distributed throughout the brain
and operating in parallel time (Berninger & Richards, 2002). Thus, multiple
breakdowns in both the phonological route (superior temporal gyrus) , the visualspatial route (angular gyrus), and the semantic route (frontal lobes) may lead to
mixed dyslexia.
(4) According to Pennington et al., (1999) the insular cortex, which may be
associated with the automatic retrieval of linguistic codes, is smaller in
dyslexics. Neuroimaging studies have demonstrated that dyslexics do not
activate this brain region when compared to controls (Corina, Richards, Serafini,
Richards, Steury, Abbott, Echelard, Maravilla, & Berninger, 2001).
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READING COMPREHENSION
Comprehension
mmn
Fluency
Phonological
Processing
3 Factors Associated with Reading Comprehension:
(1) Content Affinity – attitude and interest toward specific material.
(2) Working Memory – the ability to temporarily suspend information while
simultaneously learning new information. Working memory is the amount
of memory needed to perform a cognitive task, and hindered most by
anxiety.
(3) Executive Functioning – the ability to self-monitor and guide performance on
a given problem solving task. The strategy a student uses to decode words
as well as to organize information in a meaningful manner.
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READING COMPREHENSION INTERVENTIONS
(a) Stop and Start technique – the student reads a passage out loud, and every
30 seconds the teacher says “stop” and asks questions about the story.
Eventually the time interval is lengthened.
(b) Directional Questions – ask questions at the beginning of the text instead of
the end so students can become more directional readers.
(c) Story Maps – a pre-reading activity where graphic organizers are used to
outline and organize information prior to reading the text.
(d) Narrative retelling – have the child retell the story after reading it aloud.
(e) Read Aloud – reading out loud allows students to hear their own voices and
can facilitate working memory.
(f) Multiple Exposure – encourage students to skim the material upon reading
for the first time, with emphasis on chapter and text headings. Read for detail
on the second exposure of the text.
(g) Active Participation – encourage active reading by getting children in the
habit of note-taking or putting asterisks next to important material in the text.
(h) Create Questions – have students write their own test questions about the
material.
(i) Reduce Anxiety – anxiety inhibits working memory, and leads to ineffective
recall. Children who are anxious about reading out loud in front of their
classmates should be provided an opportunity to read in a “safety zone” in
class. This may also help to eliminate distractions as well.
(j) Medication Management – often students with attention-deficit-disorder
struggle with passage comprehension skills. Proper medication management
of the disorder can help foster better comprehension.
(k) Practice Terminology – practice defining new terms and concepts prior to
reading material with dense language. Vocabulary enrichment is often the key
to improving comprehension.
(l) Classroom Discussions – introduce new topic areas with general classroom
discussions to capture a student’s attention and interest prior to reading the
material.
(m) Sequencing Tasks – present random words out of sequence and have
children arrange them to make a sentence. Next, present sentences out of
sequence and have children arrange them to make a paragraph. Lastly,
present paragraphs out of sequence, and have children arrange them to make a
story. This type of organization drill will facilitate sequencing linguistic
material.
(n) Increase Fluency – for younger students, greater fluency allows for reading
to become a more automatic process, thereby freeing up cognitive resources to
concentrate on the passage itself, as opposed to mechanically decoding each
word in the passage.
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DEEP DYSLEXIA
4. Deep Dyslexia - a rare form of reading comprehension disorder characterized by
impairments reading words with abstract meanings, but reading more concrete,
easily imagined words are in tact (McCarthy & Warrington,1990). This disorder
may reflect the right hemisphere’s feeble attempt to read, thus explaining why
words that conjour up a visual image are read best. Semantic errors are the
hallmark of this disorder.
This is a double deficit type of reading disability as the child has poor
sound/symbol relationships and often makes semantic substitution errors when
reading aloud. Very poor rapid recognition of words.
Neuropsychological significance: * difficulty activating left hemisphere (right
hemisphere reading)
* damage to supramarginal gyrus or angular gyrus
* subcortical damage such as to the thalamus
Error Patterns of Deep Dyslexics:
Semantic Miscues
dinner……… food
occasion…… event
cemetery ….. burial
watch …….. .clock
giggle ……. . laugh
Visual Miscues
stock…….. shock
crowd …… crown
grew …….. green
saucer …… sausage
bead …….. .bread
Remediation Techniques for Mixed and Deep Dyslexia: An eclectic
approach capitalizing on the particular strengths of the child. Use multisensory of Orton-Gillingham program, Great Leaps program, and
Neurological Impress method depending upon the age, skill level, and
neurodevelopemental profile of the child.
Neuropsychology of Reading Disorders
Page 22
SUBTYPES OF DYSLEXIA
Low Incidence Types of Dyslexias:
a) Hyperlexia - the uncanny ability to decode words despite significant
cognitive deficiencies. Comprehension often very poor, though
decoding and spelling skills well developed.
Anatomical Explanation - phonological loop in tact or
preserved in spite of damage to other brain regions.
b) DeJerine Syndrome - Dyslexia without dysgraphia. The child has little
difficulty writing, though cannot read. Also known as
word form dyslexia, as child can identify words if letters
are spelled aloud (auditory input) as opposed to identifying
words from print.
Anatomical Explanation - Disconnection of visual to auditory
system via corpus callosum.
c) Neglect Dyslexia - inability to read words on left side of a page. Usually not
a developmental dyslexia, but can occur from head injury.
Anatomical Explanation - Often lesion to right parietal lobe
disrupts brain's ability to perceive and identify information
from contralateral side (left side).
d) Wernicke's Dyslexia - the inability to comprehend written material despite
adequate intelligence and word identification skills.
.
Anatomical Explanation – Damage to Wernicke’s area in
temporal lobes produces receptive aphaasia.
Neuropsychology of Reading Disorders
Page 23
90 MINUTE DYSLEXIA EVALUATION
1. Cognitive Functioning :
* WISC IV
* WJ-III
* Cognitive Assessment System
* Stanford-Binet Intelligence Scale V
* RIAS
2. Phonological Awareness:
* DIBELS
* NEPSY (Phonological Processing)
* WJ III (Sound Blending, Word Attack)
* Phonological Awareness Test (Robertson & Satter)
* Comprehensive Test of Phonological Processing (C-TOPP)
* Process Assessment of the Learner (PAL)
* Lindamood Auditory Conceptualization Test (LAC)
3. Rapid Naming Tests:
* DIBELS (Letter Naming)
* NEPSY (Verbal Fluency & Speeded Naming)
* Controlled Oral Word Association (COWA) "FAS" test
* Process Assessment of the Learner (PAL)
* Rapid Automatized Naming Tests (Denckla)
* Comprehensive Test of Phonological Processing (C-TOPP)
4. Verbal Memory Tests:
* Test of Memory and Learning (TOMAL)
* Children's Memory Scales (CMS)
* California Verbal Learning Test-Children's Version
* Rey Auditory Verbal Learning Test
* NEPSY (Comprehension of Instructions)
* WRAML-II
5. Reading Fluency Measures:
* Gray-Oral Reading Test –Fourth Edition (GORT-4)
* Woodcock-Johnson III
* WIAT II
* Curriculum Based Measurement
* Informal Reading Inventories
6. Visual Spatial Skills:
* NEPSY (Arrows)
* Jordan Left Right Reversal Test
* Bender Gestalt II
* Beery Visual Motor Integration Test
* RIAS (NIX Index)
* Rey-Osterrieth Complex Figure Test
* WJ III (Spatial Relations, Visual Matching)
* SB V (Visual-Spatial Processing)
Neuropsychology of Reading Disorders
Page 24
90 MINUTE DYSLEXIA EVALUATION
7. Executive Functioning:
* BRIEF
* Wisconsin Card Sort Test
* Delis-Kaplan Executive Functioning Scale
* NEPSY (Tower)
* Category Test
* Stroop Test
8. Family History:
KEYS TO ASSESSMENT
Under Age 7: Intelligence tests should not be interpreted solely from a level of
performance perspective, but rather should be used as a tool to determine how young
children process information. According to Lyon (1996), an early screening battery should
include specific measures of:
(1) Phonological Awareness
(2) Rapid Naming Skills
(3) History of reading difficulty in family
Ages 7 - 12: Aptitude/Achievement discrepancies certainly have some merit at this age,
but should not be used as a necessary or sufficient condition for a child to be labeled as
learning disabled. When evaluating these students, emphasis should be placed on exposure
to reading instruction as well as the aforementioned processing deficits. In addition, fluency
is an important factor as well, and can easily be ascertained by curriculum based
measurement.
Over Age 12: The primary emphasis when evaluating secondary students should be on
reading fluency and comprehension. Attentional and emotional issues can severely impact
comprehension, in addition to memory and metacognitive deficits. As stated previously,
students who have not mastered the phonological code at this age may never do so.
Particular emphasis should be placed on executive function types of issues.
Neuropsychology of Reading Disorders
Page 25
SUMMARY OF READING DEVELOPMENT
AND INSTRUCTIONAL APPROACHES
(Beitchman & Young, 1997)
Skills to Be Learned
Reading Stage
Prereading
(preschool age)


Decoding Stage (beginning
grades 1 and 2)


Transitional Reader
(beginning in grades 2 and
3)



Fluent, Independent,
Functional Reading


Deficits Associated with
RD
Recognition of letter
names and some words
(e.g., own name)
Beginning of phonological awareness (e.g.,
awareness of
similarities/ differences
between phonemes,
nursery rhyme
knowledge

Use of letter cues to
decode words
Basic correspondences
between letters or letter
combinations and
sounds

Gain fluency
Integrate decoding and
context cues
Decode automatically
and with less conscious
effort so that resources
can be allocated to
comprehension of text

Oral reading is fluent
and expressive
Silent reading for
comprehension or
information makes up
the majority of reading
activity





Instructional Approaches
Limited knowledge of
rhyme, letter names
Slowness in naming
highly familiar visual
stimuli (e.g., objects,
colors, numbers)
Training in phonemic
awareness (programs that
draw attention to sound
patterns in words), training
in the alphabet—letter
names and corresponding
sounds.
Limited phonological
processing skills
Few words recognized
by “sight”
Sounding out of
words is often
inaccurate, as is
spelling
Phonics programs that
emphasize letter-sound
correspondences, whether
in isolation or in the context
of words
Reading lacks fluency
and expressives,
although generally
accurate
Reading
comprehension is
limited
Repeated reading of
slightly challenging text to
improve fluency and
comprehension
Comprehension
problems due to poor
comprehensionmonitoring, working
memory limitations,
and limited domain
knowledge
Teaching of reading
comprehension,
metacognitive and
memory-enhancing
strategies (e.g., selfinterrogation, use of
rehearsal and elaboration),
use of advance organizers
to access background
knowledge and organize
information
Neuropsychology of Reading Disorders
Page 26
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