Reading disorders in Reading disorders in mental retardation. mental retardation.

Dyslexia or not ?Dyslexia or not ?

Annick COMBLAIN, Annick COMBLAIN, University of Liege – FAPSEUniversity of Liege – FAPSE

Department of Cognitive SciencesDepartment of Cognitive SciencesSpeech and language pathology unitSpeech and language pathology unit

Seminar « Cross views on dyslexia »Liège, 20 april 2004

ReadingReading

Complex and composite ability implying several basic Complex and composite ability implying several basic skills such as :skills such as :– Syllabic or rhyme awareness Syllabic or rhyme awareness about 4 y.o. about 4 y.o.– Phonemic awareness Phonemic awareness contemporary with reading contemporary with reading

acquisitionacquisition

In French : discovering the phonemic correspondence In French : discovering the phonemic correspondence is necessary to learn to readis necessary to learn to read

Phonemic awareness Phonemic awareness to explicit learning and to explicit learning and psychological maturational processpsychological maturational process

Positive correlation between :Positive correlation between :– phonological awareness level phonological awareness level – Reading and spelling abilitiesReading and spelling abilities

Reading and phonological Reading and phonological awareness in Down syndrome.awareness in Down syndrome.

DS individuals are able to reach a good level in DS individuals are able to reach a good level in reading reading butbut what about phonological awareness ? what about phonological awareness ? 2 point of view :2 point of view :

Cossu et al. (1990, 1993) Cossu et al. (1990, 1993)

Evans (1994)Evans (1994) DS children are able to read in DS children are able to read in

spite of low performances on spite of low performances on metaphonological tasks.metaphonological tasks.

Morton & Frith (1993)Morton & Frith (1993)

Cupples & Iaconno (2000)Cupples & Iaconno (2000) In DS as in typical children, In DS as in typical children,

reading and phonological reading and phonological awareness are strongly linked.awareness are strongly linked.

Morton & Frith (1993)Morton & Frith (1993) competence ≠ performancecompetence ≠ performance Performance on metaphonological Performance on metaphonological

tasks do not only involve access to tasks do not only involve access to phonological representations phonological representations cognitive level influence ?cognitive level influence ?

Gombert (2002)Gombert (2002) DS children = low DS children = low

metaphonological abilities (< metaphonological abilities (< to TC) but strongly linked with to TC) but strongly linked with their reading leveltheir reading level

≠ ≠ regarding the proposed regarding the proposed tasks tasks

Metaphonological tasks :Metaphonological tasks :DS children ≠ typical childrenDS children ≠ typical children

DS children : no gradual evolution rhyme perception DS children : no gradual evolution rhyme perception phoneme perception (≠ TC) phoneme perception (≠ TC)– DS : initial phoneme detection > rhyme detectionDS : initial phoneme detection > rhyme detection– 2 possible explanations :2 possible explanations :

DS : less exposed to « DS : less exposed to « language games » using language games » using rhyme rhyme

Teaching methods Teaching methods preferentially use preferentially use phonemesphonemes

DS : reading statisticsDS : reading statistics

Pueschel & Hoppmann (1993) – United States :Pueschel & Hoppmann (1993) – United States :

– 7 – 10 y.o. 7 – 10 y.o. 20% 20% – 11 – 16 y.o. 11 – 16 y.o. 47 % 47 %– 17 – 21 y.o. 17 – 21 y.o. 50 % 50 %

– 7 – 10 y.o. 7 – 10 y.o. 47 % 47 %– 11 – 16 y.o. 11 – 16 y.o. 61 % 61 %– 17 – 21 y.o. 17 – 21 y.o. 67 % 67 %

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Cognitive strategies for readingCognitive strategies for readingTChildren = DS children ?TChildren = DS children ?

Very few studiesVery few studies

Buckley, Birds & Byrne (1996) :Buckley, Birds & Byrne (1996) :

– DS children make the same errors than young typical DS children make the same errors than young typical readers :readers :

Visual errorsVisual errors Semantic errorsSemantic errors

– Use of the logographic strategy during a (atypical) long Use of the logographic strategy during a (atypical) long period period hypothesishypothesis : more difficulties than TC with the : more difficulties than TC with the alphabetic strategy acquisitionalphabetic strategy acquisition

Indicate the use of a logographic strategyNo knowledge of grapho-phonological correspondence principles.

Gombert (2002) Gombert (2002) in DS children : in DS children :

– Nonword visually ≠ known word : performance Nonword visually ≠ known word : performance – Nonword visually similar to a known words : Nonword visually similar to a known words :

performance performance

– Use of analogies with wellknown words in nonwords Use of analogies with wellknown words in nonwords readingreading

– difficulty in applying grapho-phonological difficulty in applying grapho-phonological correspondence rules to items without any lexical correspondence rules to items without any lexical relation with a wellknown wordrelation with a wellknown word

– ..

Comprehension and reading in Comprehension and reading in DSDS

reading = decoding x comprehensionreading = decoding x comprehension

Very few studiesVery few studies

The limited oral comprehension seems to limit the The limited oral comprehension seems to limit the development of reading comprehensiondevelopment of reading comprehension

What about this component ?

Observations in DS ChildrenObservations in DS Children

10 DS children aged from 7 à 11 y.o. 10 DS children aged from 7 à 11 y.o. – 5 attending special school and 5 attending normal 5 attending special school and 5 attending normal

schoolschool– Matched on the EVIP (PPVT) level Matched on the EVIP (PPVT) level µ = 6 y.o. µ = 6 y.o.

Assessed domains :Assessed domains :– Single word reading Single word reading BELEC BELEC– Sentences Sentences L2MA et ORLEC L2MA et ORLEC– Metaphonology (including names of letters and sound of Metaphonology (including names of letters and sound of

letters) letters) BELEC + Lecocq BELEC + Lecocq– Memory Memory nonword repetition ( BELEC) nonword repetition ( BELEC)– Oral comprehension Oral comprehension ECOSSE (TROG) ECOSSE (TROG)– Prerequisite for the first school grade Prerequisite for the first school grade NBA-T : spatial NBA-T : spatial

organisation; rhythm, visual discrimination, graphic organisation; rhythm, visual discrimination, graphic skills and memory (visual and auditive)skills and memory (visual and auditive)

0

10

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Lettr

es

Graph

emes

Phon

o.Awar.

Compr

ehen

sion

Rhythm

Discrim

inati

on

Grahic s

kills

Spat.

Org.

Special school

Normal school

Results (%)

0.01

0.05

0.05

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10

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40

50

60

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80

90

100

Subject1

Subject2

Subject3

Subject4

7y.o.

TC

SNW

LNW

SNFW

LNFW

SFW

LFW

Nonwords, non frequent words and frequent words

•No frequency effect frequent words vs non frequent words : p=0.55

•No lexicality effect : •nonwords vs frequent words : p=0.98•nonwords vs non frequent words : p=0.56

•No length effect short words vs long words : p=0.30

•No complexity effect simple words vs complex words : p=0.68

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10

20

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50

60

70

80

90

100

Subject1

Subject2

Subject3

Subject4

Subject5

7y.o.

Regular word

irregular word

Regular and irregular words

• No regularity effect

• Most frequent errors :1. Omission of one or more syllables2. Phoneme omission 3. Confusion of visual similar letters (b/d)4. Confusion of non voicing / voicing consonants (p/b)