Identification

IQ-achievement discrepancy: If a child has a specific disability, performance on general ability (IQ tests) will be significantly higher than achievement tests of the specific impairment

• Discrepancy should be severe or significant
• In practice, often a difference of ≥ 2 SDs is employed 

--> moeilijk om deze manier te gebruiken, omdat je niet weet of een kind slecht presteert of een impairment heeft (misschien is een slim kind wel verveeld)

Below average achievement: 

• Identification of poor achievement by comparing standardised test results with those of peers of the same age 
• Poor achievement of ≥ 1 or 2 SDs is often employed in practice (but varies from country to country) 

Wat deze modellen niet dekken: wat heeft een kind nodig, deze modellen zijn erg zwart-wit

Response to intervention: in hoeverre werkt een interventie

Wat doen kinderen met de uitleg/intervention

Classification of language disabilities

DSM-5: communication disorders

1. Persistent difficulties in the acquisition and use of language across modalities due to deficits in comprehension or production
   
   1. reduced vocabulary 
   2. limited sentence structure 
   3. impairments in discourse 
2. Language abilities are substantially and quantifiably below those expected for age resulting in functional limitations in effective communication, social participation, academic achievement, or occupational performance, individually or in any combination. 
3. Onset of symptoms is in the early developmental period 
4. The difficulties are not attributable to hearing or the other sensory impairment, motor dysfunction, or another medical or neurological condition and are not better explained by intellectual disability (intellectual developmental disorder) or global developmental delay. 

DSM-5: specific learning disorders

1. Difficulty learning and using academic skills in specific areas such as decoding words, reading comprehension, spelling, written expression, or mathematics skills for at least 6 monthsdespite the provision of interventions that target those difficulties.
2. The level of specific academic skill is substantially below what would be expected given the chronological age. This significantly interferes with academic performance or other areas of daily living. 
3. The learning difficulties began during school-age years. 
4. The learning difficulties are not better accounted for by other individual factors such as the presence of an intellectual disability, inadequate exposure to academic instruction in the language of proficiency, psychosocial adversity, or other mental or neurological disorders. 

Language disabilities

Expressive: niet kunnen praten/problemen met praten

Receptieve: niet begrijpen wat anderen zeggen

• Kinderen met SLI gebruiken kortere zinnen, grammaticaal incorrecte zinnen
• Geen duidelijke symptomen van SLI 
• Probleem: de meeste informatie wordt verbaal gegeven, dus als een kind dat niet begrijpt is het moeilijk te testen (ook zo met IQ-testen) 

Speech sound disorder(SSD): niet kunnen produceren van klanken/ problemen met articuleren (developmentally dialect geluiden) 

• Geen fysieke abnormaliteiten (bijv in de tong of mond) 

Language disorders: moeilijkheden in het begrijpen of produceren van vocabulaire, zinnen en spreken

Prevalence: 3-7% (afhankelijk van de studie); hoger voor jongens, dan voor meisjes; hoger voor lage sociale klassen.

Oorzaken:

• Gelimiteerde informatie-processing capaciteit 
• Moeilijkheden in auditory processing: het horen van verschillen tussen woorden (beer-peer)
• Gebrek in hun verbale korte termijn geheugen en fonologisch geheugen 
• Genetische vatbaarheid (erfelijk)

Developmental course

• Improvement to normal range over time is possible 
• Risk for later impairment: 
  
  • Articulation problems < expressive problems < receptive problems
• Especially if at the age of 5-6 the problems have not diminished significantly, there is a risk of continued language impairment:
  
  • Language disabilitiesàreading disabilities, socio-emotional problems etc 

Learning disabilities - 3 types

• Impairments in reading: 
  
  • Word reading accuracy
  • Reading rate or fluency
  • Reading comprehension 
• Impairments in written expression:
  
  • Spelling accuracy
  • Grammar and punctuation accuracy
  • Clarity or organisation of written expression 
• Impairments in mathematics: 
  
  • Number sense
  • Memorisation of arithmetic facts 
  • Accurate or fluent calculation 
  • Accurate maths reasoning 

Reading en writing disabilities (dyslexie)

• International Dyslexia Association: 
  
  • Dyslexia is a neurologically-based, often familial, disorder which interferes with the acquisition and processing of language. Varying in degrees of severity, it is manifested by difficulties in receptive and expressive language, including phonological processing, in reading, writing, spelling, handwriting, and sometimes in arithmetic. 
  • Dyslexia is not the result of lack of motivation, sensory impairment, inadequate instructional or environmental opportunities(RTI), or other limiting conditions (IQ discrepancy). 
  • Although dyslexia is lifelong, individuals with dyslexia frequently respond successfully to timely and appropriate intervention. 

Processes involved

• Phonological processing
  
  • Using the sound structure of language to process written material 
• Phonological awareness --> begrijp dat woorden bestaan uit verschillende klanken (foneem)
  
  • Understanding that words are composed of separate sounds (phonemes)
• Phonological decoding --> begrijp dat relatie tussen geluiden en letters 
  
  • Relationship between phonemes (=sounds, auditory) and graphemes (=written letters) 

Letter-sound intergration heeft invloed op reading and writing en phonological processing en phonological processing heeft invloed op letter-sound intergration.

Specific impairments

• Reading:
  
  • Word-level reading (phonological decoding) - Fluency
  • Comprehension 
• Writing
  
  • Transcription (punctuation, capitalisation, complex words, handwriting) = de basis
  • Text generation (Sentence construction, planning, linking ideas, discourse) 

Hoe zit het in het brein?

• Disruptions in posterior perisylvian areas in the left hemisphere - Both at the neurofunctional and anatomical level 
• Important for processing of speech sounds • Fusiform word form area 
  
  • In left hemisphere.
  • Underdeveloped.
  • Specialises in fast recognition of letter combinations 

Mensen met dyslexie gebruiken anderen pathways in de hersenen. Je hoeft niet te weten waar de gebieden zitten.

Oorzaken

• Genetic predisposition
  
  • 30-50% of child who has a parent with reading disability will develop the same disability - 85% concordance in monozygotic, 50% in dizygotic twins
  • High genetic correlation between different learning disorders, high co-occurrence 
• Niet meer bekend 

Early signs of reading and writing problems --> zie boek

(Contributing factors uitwerken)

Prevalence

• 4-10% van de kinderen
• Verschillende per taal

Orthografische transparantie: hoe verhouden dezelfde letters zich in verschillende woorden.

Course

• Reading and writing disabilities persist into adulthood
  
  • Compensatory skills --> komen er op een andere manier
  • Some children catch up, as a result of intensive intervention in primary school
  • Socio-emotional and motivational characteristics 
• Matthew effect: Gap between high and poor performing readers becomes wider over time --> het verschil wordt steeds groter 
  
  • Waarom: difficulty in reading and writing à avoidance à intensification of problems 

Mathematical disabilities (discalculie)

• Severe difficulty in mathematics, not explained by general cognitive difficulties or educational opportunities 
• Prevalence: 5-8% 
• Has genetic component (runs in families) 
• Understudied compared to reading and writing disabilities 
• Many brain regions involved
  
  • Frontal: strategy choice and planning
  • Parietal: representation of quantity
  • Occipital: visual identification of numbers
  • Temporal: verbal processing and memory of arithmetic facts 

Developmental symptoms

Achterlopen in het verkrijgen van tellen en optel-strategieën; maar ook: het herinneren van numerieke feiten en problemen met woorden.

Core cognitive symptoms

• Difficulty representing quantity (“number sense”) 
  
  • Slow to compare numbers 
  • Slow to enumerate 1-3 objects (“subitising”) 
  • Slower counting speed 
• Number symbols processed less automatically 
  
  • Number stroop task
• Memory retrieval of number facts is disturbed 

Likely other symptoms

Difficulty with:

• Using finger counting (slow, inaccurate, trouble recognising finger configurations
• Decomposing numbers (e.g. recognising that 10 is made up of 4 and 6)
• Understanding place value (number sense) 
• Learning/understanding multi-step calculation procedures and problem-solving 
• Anxiety about or negative attitude towards maths 

Causes

• Genetic predisposition 
• Quality of instruction? 
• Anxiety? 

• Visual-spatial difficulties
  
  • Trouble processing what the eye sees 
• Weakness in visual processing of numbers and mathematical situations 
• Auditory processing difficulties 
  
  • trouble processing and making sense of what the ear hears. 
• Attention deficits 
• Memory problems 
• Information processing deficits 
• Motor disabilities 
• Problems with sequencing, organising information 
• Problems with understanding concepts and symbols 

Course

• With remedial teaching and/or therapy some problems can be alleviated 
• However, most children with severe MD will remain problems into adulthood 
• In adulthood: 
  
  • Blocked from certain professions (lower salary)
  • Difficulty managing money
  • Difficulty understanding statistics/numbers (influence on decision making), but also reading the time 
  • Low self-esteem, anxiety, avoidance 

Zie het schema aan het einde van de slides!