cognitive profile of higher education students with dyslexia wim tops maaike callens marc brysbaert

Cognitive profile of higher education students with dyslexia

Wim TopsMaaike CallensMarc Brysbaert

Issue

• An increasing number of postsecondary students start higher education with a diagnosis of dyslexia.

• However, relatively little is known about this group, except for the assumption that they have worse reading and writing skills.

• Is particularly true for non-English speaking countries

Issue

• Great need for clarification, guidelines, and regulations.

• No general standards for compensatory measures based on scientific evidence.

• Clinical experience of the local office of disability services and their considerations tend to prevail.

Issue

• In the absence of theoretical and empirical evidence for the efficacy of the special measures, lecturers object that:– “dyslexic” students may be asking needless exceptions– which create extra work,– and are unfair to the other students.

• Some lecturers even doubt whether students with a diagnosis of dyslexia belong in higher education, questioning their cognitive skills and work attitude.

Issue

• Also for students with reading disabilities the lack of empirical evidence is a problem– there is little solid advice about how to optimize

their studies– manuals based on clinical and educational practice

rather than empirical evidence– nearly all focus on English (orthographic depth,

differences in educational policies)

Cognitive profile of HEstudents with dyslexia in English

• 1990s: studies addressing the question whether individuals with dyslexia continue to have problems with reading and spelling in adulthood, or whether remediation teaching and reading practice in primary and secondary education are able to bridge the initial lag

• Conclusion: reading and writing problems remain

Cognitive profile of HE students with dyslexia in English

• Hatcher, Snowling, and Griffiths (2002)– compared the cognitive skills of 23 university

students with dyslexia and 50 matched controls– participants completed 17 tasks assessing:

• literacy (reading and writing), • processing skills (perceptual speed, memory span, and arithmetic), • phonological skills (spoonerisms and rapid naming), • verbal fluency, • verbal abilities (vocabulary test), • non-verbal abilities (Raven matrices), • self-reported problems in attention and organization.

Cognitive profile of HEstudents with dyslexia in English

• Hatcher, Snowling, and Griffiths (2002)– The dyslexic students performed worse on all but

the two tasks of general cognitive abilities (WAIS vocabulary and Raven matrices).

– Expressed as an effect size

Hatcher et al. (2002)LITERACYWord reading 1.14Now-word reading 1.47Word spelling 1.31Text writing 1.12PROCESSING SKILLSPerceptual speed 0.89Short-term memory span 1.05PHONOLOGICAL SKILLSPhonological processing 1.32Rapid naming 1.19VERBAL FLUENCYSemantic fluency 0.46Rhyme fluency 1.26GENERAL INTELLIGENCEArithmetic 0.58Vocabulary 0.10Problem solving / reasoning -0.01

Hatcher et al. (2002)

• Dyslexic students further reported more problems with– Memory: “I easily forget about what has been

said”, – Attention: “I lose track in required reading”, – Effort: “I do not work to my potential”, – Affect: “I am sensitive to criticism”, – Organizing and activating: “I have difficulty getting

organized and started”

Meta-analysis

• Swanson and Hsieh (2009) – 52 published articles – 776 comparisons

S&H09 HSG02LITERACYReading comprehension 1.20Word reading 1.37 1.14Now-word reading 1.33 1.47Word spelling 1.57 1.31Text writing 0.72 1.12PHONOLOGICAL SKILLSPhonological processing 0.87 1.32Rapid naming 0.96 1.19GENERAL INTELLIGENCEArithmetic 0.75 0.58General intelligence 0.20Verbal intelligence 0.63Vocabulary 0.71 0.10General information 0.47Problem solving / reasoning 0.11 -0.01Verbal memory 0.62

S&H09Visuospatial memory -0.39Cognitive monitoring 0.27Perceptual motor skills -0.13Auditory perceptual -0.18Visual perceptual 0.13Social and personal skills 0.10Personality 0.28Neuropsychological (e.g., EEG) -0.02Ratings by third persons -0.23

Replication Hatcher et al. (2002)

• Other language and educational system (university access regulations)

• A wider range of tasks– Strengths?– Heterogeneity?– L2?

• Samples large enough to detect everything that is interesting (d > .40)

• 100 + 100 controls

2

²² controldyslexic

controldyslexic

SDSD

MeanMeand

A new study

• 200 first bachelor students– Dutch native speakers– Normal or corrected to normal vision

• Allows us to find effect sizes from d = .4• These are effect sizes that start to require

special arrangements

A new study

Participants

• 100 students with assessment of dyslexia– Both university and non-university– Mean age

• Comorbidity was no exclusion

Participants

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Dyscalculia+ASS

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Participants

• Diagnosis of dyslexia based on 3 criteria according to the Dutch Dyslexia Foundation (SDN, 2008)– Clinical scores on word reading and/or spelling– Resistance to instruction– Exclusion

Participants

• 100 controls– With no known neurological or functional

deficiencies– Matched on field of study, age and gender

Participants

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A new study

• Tests– IQ (KAIT: fluid vs. crystallized intelligence)– Speed of processing (selective attention and task

switching)– Word reading (one minute test in Dutch and

English)– Nonword reading (one minute)

Tests

Tests

A new study• Tests– Test for Advanced Reading and Spelling• Various STM spans• Phonological awareness (spoonerism & reversals)• Rapid naming (various stimuli)• Vocabulary• Text reading (aloud)• Text comprehension (visual and auditory presentation)• Word spelling

– English word spelling– Arithmetic (four operations)

Tests

Tests

Tests

Tests

Tests

A new study

• Learning and Study Strategies Inventory (LASSI; Lacante & Lens, 1999)

• Personality Inventory (NEO-PI-R; Hoekstra, Ormel, & de Fruyt, 2007) based on the big five– Extraversion– Neuroticism– Agreeableness– Openness– Conscienciousness

Tests

Tests

Results reading

Word reading Dutch (EMT)

Total number read words 1.87Number of errors 0.67Correctly read words 1.97Word reading English (OMT)Total number read words 1.36Number of errors 0.59Correctly read words 1.40Pseudoword reading (de Klepel)Total number read words 1.50Number of errors 0.44Correctly read words 1.59Reading text aloud (GL&SCHR)Substantial errors 0.98Time consuming errors 0.64Reading time 1.29Silent text reading for comprehension (Tekenbeet)Words per minute 1.13Text comprehension (GL&SCHR) 0,47

Results writing

Word spelling Dutch (GL&SCHR)

Weighted score word spelling 2.28Correct word spelling 2.05Writing speed 0.43Proofreading 1.08Word spelling English (WRAT)

Correctly spelled words 1.50Sentence writing (AT-GSN)

number of errors 2.10Morphology and syntax (GL&SCHR)

Weighted score 0.91Total score 0.87

Results phonological processing

Phonological awareness (GL&SCHR)Number correct spoonerisms 0.70Spoonerisms time 1.42Number correct reversals 1.00Reversals time 1.30

Results rapid naming

Rapid naming (GL&SCHR)

Letters 1.02

Digits 1.05

Colours 0.81

Objects 0.24

Results IQGeneral Intelligence (KAIT) Total IQ 0.38Crystallized IQ 0.55Fluid IQ 0.13

Definitions 0.75Auditory comprehension 0.09

Double meanings 0.43Famous persons 0.35Symbol learning 0.07

Logical reasoning 0.12Secret codes -0.13

Block patterns -0.17Symbol memory 0.03

Auditory memory 0.37

Results attention

Processing speed (CDT)

Working pace 0.90

Concentration 0.67

Number of errors 0.09

Number of missed digits 0.14

Results memory span

Short term memory

STM phonemes 0.71

STM shapes 0.28

STM words 0.30

Memory with sorting 0.45

Results arithmetic

Mental calculation (TTR)

Total number calculations 1.05

Addition 0.97

Subtraction 0.61

Multiplication 0.90

Division 1.00

Mixed operations 1.12

Results Personality

NEO-PI-R

Neuroticism 0.26

Extraversion 0.19

Openness 0.09

Altruism -0.02

Conscientiousness -0.14

Results study strategies

Learning and study strategies inventory (LASSI)

Attitude -0.02 Motivation 0.31 Time management -0.09 Fear of failure -0.07 Concentration 0.37 Information processing -0.06 Selection of main ideas -0.36 Study competence 0.31 Self evaluation 0.20 Test strategies -0.10

Interim conclusions

• The differences on the IQ test are negligible and particularly caused by definitions to words (d = .6).

• There are no differences in fluid intelligence (d = .1).• Dyslexic students tend to be slower than controls in

processing speed (as measured with the CDT; d = .6), but they do not make more errors (d = .1).

• Except for phonological short-term memory (d = .6), memory spans are quite comparable (d < .4).

Interim conclusions

• There is considerable dyslexia cost for arithmetic (d ≈ 1), which tends to be larger for divisions and multiplications than for subtractions.

• There is a considerable cost (d ≈ 1) for phonological processing due to the speed of processing, not to the accuracy of processing.

• There are no differences in the personality and study strategies inventory.

Optimising assessment protocols

• Two sessions of 3 hours• What’s the minimum we need for good

assessment?• Hatcher et al. (2002): About 95% of the

students could be classified correctly on the basis of four tests only: spelling, word reading, verbal short term memory, and writing speed.

Optimising assessment protocols

• Post-diction vs. prediction (Ockham’s hill; Gauch, 2002)

• Classification with 10-fold cross validation resampling method (Kuhn, 2008)

• 3 variables: 91% prediction – Dutch word reading,– Dutch word spelling– phonological awareness task (reversals time)

Writing skills beyond spelling

• Simple informative text about tick bites (written for 13-year olds)

• Participants were asked to read the text silently and to write a summary (no time limits)

• Summaries blindly scored by teachers:– Handwriting quality– Quality of texts (typed and corrected for spelling

errors)

Writing skills beyond spelling

• Handwriting (Likert-scale 1 – 5)–Dyslexia: 2.63–Control: 2.79–d = .15 (n.s.)

• Text quality:–No significant structural differences (words

used, sentence length, …) except for number of long words used

Writing skills beyond spelling

• Judgment text quality by teachers• General score (Likert 1-7):–4.85 vs. 5.68 (d = .4*)

• No significant differences for conciseness, vocabulary, and sentence structure

• Difference due to text structure and text agreeability

General conclusions

• Despite the differences in language and educational context, our findings are remarkably similar to those in English.

• The pattern of strengths and weaknesses of students with reading disabilities is very much the same in Dutch.

• This is good news, because it indicates that the profile is applicable to most alphabetical languages.

General conclusions

• Our findings are further noteworthy because they agree well with the traditional definition of dyslexia as a combination of normal intelligence with deficient reading and writing.

• This definition has been questioned in the past years, partly because a discrepancy between verbal and general abilities is very difficult to measure reliably at individual level.

General conclusions

• Dyslexic students in higher education particularly fail in processing speed, not in accuracy.

• They did not make many more errors in reading and other tasks, except for writing.

• Also encouraging is the finding that students with dyslexia tended to perform better on the text comprehension test when the text was read out.

General conclusions

• Three tasks captured all systematic variance in our study– Sentence level did not add anything to word

level– L2 processing did not add anything–Nonword naming did not add anything

(language-specific?)

Special arrangements

• Software that helps with reading and writing.• Extra time for exams.• Use of calculator (?)• Training in higher-order writing skills• Better information for students themselves, so

that they can adapt their studies to their weaknesses and strengths.

Thanks for your attention!

Contact w.tops@rug.nl