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transcript

The debate

Sydney University –

5

th

August, 2015

Does

dyslexia

exist?

Poor readers are failed by the establishment

is “…a cruel fiction… no more real than the 19th century scientific construction of ‘the æther’ to explain

how light travels through a vacuum”

“…to label children as because they’re confused by poor

teaching methods is wicked… The sooner it is consigned to the

same dustbin of history, the better”

Graham Stringer MP (2009)

A universal scenario

“A 22 year old woman was condemned to

‘temporary menial tasks’, the High Court heard. P.P. claims that she is of average intelligence but because her learning difficulty was not discovered until two months before she left school, she never learned to read and write properly….. Tests were carried out at infant, junior and comprehensive schools. At the age of 10 she was found to be four years behind in reading and writing skills but the reason was never identified”

(The Guardian, 27.7.97)

A simple definition of

?

is evident when accurate and fluent

word reading and/or spelling develops very

incompletely or with great difficulty

This focuses on literacy learning at the ‘word’

level and implies that the problem is severe

and persistent despite appropriate learning

opportunities

= reading disability

Too inclusive for some; too

exclusive for others

anyone who struggles with

accurate and/or fluent

decoding

those who score at the lower

end of the normal distribution

on an appropriate test of

reading accuracy or fluency

those for whom decoding is

merely one element of a more

pervasive condition

marked by a range of

comorbid features

those whose decoding

problems are biologically

determined

Can genetics and

neuroscience inform

us.... who has

?

The brain does not have “the part(s)” for reading

• Reading in the brain unfolds via a complex

chain of activation of various structures,

which is distributed in space and in time

–There is no brain “locus” for reading, but there is a

“reading brain”

–The “reading brain” is a developmental stage of the

brain –We are born with an “illiterate brain” that has the

capacity to become a “reading/literate brain”

• This chain is malleable

–Developmentally –As a result of interventions

Approaches to studying the brain

• magnetic resonance imaging (MRI)

• functional magnetic resonance imaging (fMRI)

• voxel-based morphometry (VBM)

• diffusion tensor imaging (DTI)

• magnetic resonance spectroscopy (MRS)

• positron emission tomography (PET)

• magnetoencephalography (MEG)

• electroencephalography (EEG)

those whose decoding

difficulties cannot be

explained in alternative ways e.g. because of severe intellectual or sensory impairment, socio-economic disadvantage, poor schooling, or emotional/behavioral difficulty

Emotional/behavioural difficulties

a) Strong association between dyslexia and internalising disorders

b) Link with externalising behaviours (in school and juvenile justice system)

c) Comorbidity with ADHD

(25-40%) with one meet the

criteria for the other

d) Appears to be more related

to inattention than

hyperactivity

those for whom there is a

significant discrepancy

between decoding

performance and IQ

The lazy and the stupid

Don’t believe everything you read in the newspapers!

those whose decoding

difficulty is deemed to be

unexpected

those whose poor decoding

skills contrast with strengths in

other intellectual and

academic domains

Mathematics

RD and MD co-occur in 30-70% of

those with either disorder (others

also report studies ranging widely)

But co-morbidity declines as

selection criteria become more

stringent

those whose decoding

problems are marked by

certain associated cognitive

difficulties

those with a history of very

poor spelling

those poor decoders who also

present with a range of

symptoms commonly found in

those with

e.g. poor motor, arithmetical, or language skills, visual difficulties, and low self-esteem

those who demonstrate a discrepancy between decoding and listening comprehension

those who fail to make

meaningful progress in

decoding even when provided

with high-quality, evidence-

based forms of intervention

A normal distribution of any key cognitive process

0

disabled?

highest achievers

low

achievers

high

achievers

Cognitive level explanations

a) Phonological deficit hypothesis

b) Rapid naming and the DD

c) STM/WM deficits

d) Auditory/speech processing

e) Visual processing/attention

f) Magnocellular problems

g) Scotopic sensitivity

h) Sluggish attentional shifting

i) Visual attention span deficit

j) Abnormal crowding

k) Anchoring deficits

l) Psychomotor processing

Phonological deficit hypothesis Does it include phonological awareness sometimes

used as the superordinate construct), rapid naming and

verbal STM/WM?

Phonol. Aw = the ability to detect and manipulate

the sounds of spoken language (phoneme and syllable

levels)

Phonemic Aw = the ability to segment

spoken words into phonemic elements

Phonological deficit hypothesis Phonemic awareness is the strongest predictor of

children’s word reading skills

But…

Prediction strongest in the early years

May be less important for transparent languages

Weaknesses do not always result in RD, and not all

those with RD demonstrate a Phon. difficulty

Continuing lack of theoretical clarity

Question mark over relevance for intervention

Rapid automatized naming (RAN)

and the double deficit Predictive power is greater for poorer readers

Better predictor for younger readers

Predictive importance is greater in transparent

languages

Ltd evidence of poor RN but no Phonol deficits

Theoretical uncertainties about what RAN actually is

Doubts as to whether naming speed can be

improved and, if so, whether this can improve

reading performance

Working Memory Children with WM difficulties tend to perform poorly on

a range of academic tasks

Significant proportion of poor readers do not evidence

memory problems (large variation across studies)

Prediction typically weaker than for phonemic

awareness or RAN

May not add much when other phonological processes

are considered in multivariate studies

Does not inform intervention beyond teacher

sensitivity

Cognitive level explanations

a) Phonological deficit hypothesis

b) Rapid naming and the DD

c) STM/WM deficits

d) Auditory/speech processing

e) Visual processing

f) Magnocellular problems

g) Scotopic sensitivity

h) Sluggish attentional shifting

i) Visual attention span deficit

j) Abnormal crowding

k) Anchoring deficits

l) Psychomotor processing

Auditory processing

Continuing doubt as to:

The proportion of poor readers who encounter

such difficulties

The developmental trajectory of A.P. skills

Whether there is a causal relationship with RD

How this work can inform intervention

Visual attention

Concerns the ability to select rapidly

the most relevant visual information.

Psychomotor difficulties

Estimates of motor impairments in

RD/dyslexic samples range from 30-65%

Evidence for a causal relationship is weak Argued by Nicholson that but both reflect an underlying cerebellar impairment Ltd role for intervention

To what

extent does a

diagnosis of

guide the

educator in

devising

appropriate

forms of

treatment?

Forms of training

• Cognitive

• Auditory

• Visual

• Motor

The American Academy of Pediatrics' joint technical report

(Handler, et al., 2011).

"Scientific evidence does not support the claims that visual

training, muscle exercises, ocular pursuit-and tracking exercises,

behavioral/perceptual vision therapy, training glasses, prisms,

and colored lenses and filters are effective direct or indirect

treatments for learning disabilities. There is no evidence that

children who participate in vision therapy are more responsive

to educational instruction than those who do not participate.

The reported benefits of vision therapy, including nonspecific

gains in reading ability, can often be explained by the placebo

effect, increased time and attention given to students who are

poor readers, maturation changes, or the traditional remedial

techniques with which they are usually combined” (p. e847).

The Royal College of Opthalmologists

argues that “…manipulation of the

visual system using colour to facilitate

reading lacks scientific support”.

In consequence, a recent editorial in

the BMJ (Aug, 2014) has called upon

dyslexia charities to desist in providing

an inaccurate view of the evidence

Forms of training

• Motor

"Process training has always made the

phoenix look like a bedraggled sparrow. You

cannot kill it. It simply bides its time in exile

after being dislodged by one of history's

periodic attacks upon it, and then returns,

wearing disguises or carrying new noms de

plume, as it were, but consisting of the same

old ideas, doing business much in the same

old way (Mann, 1979, p.539).

Practitioners should:

“…shift the focus of their

clinical activities away from

emphasis on psychometric

assessment to detect cognitive

and biological causes of a

child’s reading difficulties for

purposes of categorical

labelling

.... in favour of assessment

that would eventuate

educational and remedial

activities tailored to the child’s

individual needs”

Vellutino et al. ( 2004 )

Multisensory teaching?

RTI and the question of the

equitable use of resources

Some RTI issues:

• When should screening take place?

• Should it be multistage

• What are the best predictors?

• How stable are problems/progress?

• Should intervention be standardized?

• Should Tier 2 always precede Tier 3?

• What are the needs of the older child

• Why are standardized measures necessary?

• How can programs be rendered more

powerful?

The way forward

for H.E.?

The Conversation : Elliott, J.

( June 18th , 2015 ) . Special exam arrangements for

dyslexia veering out of control.

The era of applying the label 'dyslexic 'is rapidly

drawing to a close. The label has served its function

in drawing attention to children who have great

difficulty in mastering the arts of reading, writing

and spelling but its continued use invokes emotions

which often prevent rational discussion and

scientific investigation (Yule, 1976, p. 166).

(Mum)… had paid around £2,000 on commissioning five independent reports showing how bright and

intelligent Alex was despite his condition – and how

Maple Hayes was the perfect place for his

secondary education, with its specialist programmes

and intensive teaching.

“Alex is not stupid, he is dyslexic,” she had said.

“Every child is entitled to the education they need. This is

clearly not being met in Alex’s case. He needs

specialist dyslexia tutoring before it is too late. My son

is being let down severely by

the school system.’’

The dyslexia meme The power of the dyslexia label is

rooted in

a) our natural desire to have a

diagnostic term for our

difficulties

b) its ability to foster a more

positive conception of self

c) its leverage with teachers and

the gatekeepers to educational

resources

d) its ability to gain public

attention and concern for the

need to address a range of very

real and often severely

distressing difficulties

Words of counsel…

“Maybe you are still too young, or unworldly to understand some things in life.

In my experience, many things are better kept quiet, or left unsaid.”

Lipstick and Kisses