understanding dyslexia

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Understanding Dyslexia. Ros Lugg. Dyslexia or Specific Learning Disability?. Other Specific Learning Disabilities. ADHD (Attention Deficit Hyperactivity Disorder) Dyspraxia Dysphasia, speech/language delay or deficit Dyscalculia Autism/Aspergers Syndrome/Tourette Syndrome. - PowerPoint PPT Presentation


  • Understanding DyslexiaRos Lugg

  • Dyslexia


    Specific Learning Disability?

  • Other Specific Learning DisabilitiesADHD (Attention Deficit Hyperactivity Disorder)DyspraxiaDysphasia, speech/language delay or deficitDyscalculiaAutism/Aspergers Syndrome/Tourette Syndrome

  • Developing awareness 1898 Pringle Morgan (Percy) 1920s onwards Samuel OrtonStrephosymbolia

    Steinpost-mortem evidence

  • 2007 New Zealand recognises dyslexia!

  • Types of dyslexiaDevelopmental Dyslexia inherited condition from birth. Affects approximately 10% of the population.

    Acquired Dyslexia a result of brain injury

  • Dyslexia is a complex neurological condition which is constitutional in origin. The symptoms may affect many areas of learning and function, and may be described as a specific difficulty in reading, spelling and written language. .oral language may be affected to some degree.

    British Dyslexia Association 1996

  • Neurological and biological basis

  • Brain structure MRI scanning results

    The planum temporale cortical language area, which is normally larger in the left hemisphere than in the right, is symmetrical in most dyslexics.

  • The corpus callosum is physically less well developed in dyslexics than in non-dyslexics.

  • Nutritional aspects Dyslexics are less able to convert EFAs to myelin in the brain

  • Males are more vulnerable than females to EFA deficiencies (Burdge et al 2002 + other studies)

  • Visual and auditory symptoms in dyslexia have been related to physical signs consistent with fatty acid deficiency. (Taylor et al., 2000)

  • In children and adults, the same physical signs suggestive of fatty acid deficiency have also been linked with both dyslexia (Richardson et al., 2000) and autistic spectrum disorders (Bell, Sargent, Tocher & Dick, 2000, 2004).

  • Link between Dyslexia and EFAs Two groups of mothers extensive questionnaire about diet while pregnant (particularly Omega 3 & 6 consumption)

    One group dyslexic sons

    One group non-dyslexic classmates

  • Study found that:

    Mothers of children with dyslexia had consumed significantly less EFA while pregnant than mothers of non-dyslexic children.

  • Supplementation with EFAs can be extremely effective

  • Brain activation fMRI scanning results

    Dyslexics were scanned while doing a simple rhyming task.

    In normal readers, the left frontal cortex lit up, but this does not happen in dyslexics.

  • Graduate dyslexics studyWell-compensated graduate dyslexics studied.

    Equivalent non-dyslexic control group

    Simple rhyming task

  • PET scan findingsBoth groups completed the tasks with no problem.

    Dyslexic group very different pattern of brain activity:

    Less activity in Brocas and Wernickes areas and no activity at all in the insula

  • ConclusionA specific failure in that particular brain system connected with language persists into dyslexics adult lives, although their performance indicates that they were compensating well.

  • Effect of correct remediation Several studies have shown that brain activation patterns can be changed with the right remediation even in adults.

  • Magnocellular pathways Dyslexic brains show abnormalities of the magnocellular component of the visual system, which is specialized for processing fast temporal information.

  • Current conclusions The evidence is consistent with an increasingly sophisticated account of dyslexia that does not single out either phonological or visual or motor deficits. Rather, temporal processing in all three systems seems to be impaired. Dyslexics may be unable to process fast incoming sensory information adequately in any domain.

  • Gene linksChromosome 6 (DCDC2) linked with dyslexia Chromosome 15 (KIAA0319) also implicated

    Genetic abnormalities in Brocas and Wernickes areas (the main language areas in the left hemisphere)

  • HeritabilityDyslexia runs in families!

    If a boys father is dyslexic, he has a 40% chance of being dyslexic.

    If his mother is dyslexic, he has a 50% chance of being dyslexic.

    Boys are 4 times more likely to be dyslexic than girls.

  • Links with other conditionsLeft-handednessEczemaAllergiesSchizophreniaDyspraxiaADHDGlue earIrlen Syndrome

  • Dyslexia and behaviour Internationally, 60 80% of prison populations are dyslexic

    Dyslexia causes huge anxiety and self-esteem problems, particularly with brighter pupils. This magnifies behavioural issues at school age and beyond.

  • Fallacies about dyslexia

    Hes not ready for reading yet. Wait until hes ready and hell be fine.

    Dyslexia doesnt exist. Its just a middle-class parents excuse for a thick child.

  • Possible IndicatorsObvious good or bad days with no reasonConfusion between directional wordsDifficulties with sequences, days, months, tablesFamily historyDiscrepancy between oral and written languageReversals/mis-sequencing letters

  • Poor concentrationForgets or misunderstands instructionsHas difficulty understanding what has been readTakes longer to do written workSlow processorProblems copying, particularly from the boardProblems planning essays

  • Poor confidence or self-esteemPoor social skillsCan appear awkward or clumsyVery inconsistent abilitiesUnexpected difficulties with certain tasksSometimes tongue-tiedAnxious about answering questions in class

  • Home and social implicationsFatigueHomeworkOrganisationSocial isolation

  • Possible strengthsInnovative thinkersExcellent trouble shootersIntuitive problem solvingCreative arts, architecture, design, engineeringLateral thinkersOften excellent with computersOften brilliant higher level mathematicians

  • Famous dyslexicsAlexander Graham Bell Nelson RockefellerJohn Britten Henry FordThomas Edison Walt DisneyMichael Faraday CherErin Brockovich John LennonGeorge Patton Auguste RodinOrlando Bloom Nigel KennedyTom Cruise Henry Winkler

  • Whoopi Goldberg Jackie StewartSusan Hampshire Muhammed AliKeanu Reeves Thomas JeffersonKiera Knightly Winston ChurchillOliver Reed J F KennedyRobin Williams George WashingtonLeonardo da Vinci Agatha ChristiePicasso W B YeatsAndy Warhol Terry Goodkind

  • Patterns of difficulty One feature of dyslexia is that there is no link between dyslexia and intelligence.

    There are typical patterns, but huge variability between individual difficulties.

  • Perception and Processing

  • Perception and Processing Model

    Output Retrieval/planning/expressionInput Reception v. PerceptionComprehension, organization, retention

  • Processing skills(The big 5)Motor development (fine and gross) SequencingPhonological awarenessVisual perception (Visual discrimination)Memory (working)

  • Memory implicationsA non-dyslexic child takes between 4 and 10 exposures to a word to fix it in long-term memory.

    A dyslexic child can take anything between 500 and 1300 exposures.

    Therefore: teaching needs to incorporate huge amounts of overlearning

  • Understanding MemoryShort v long-term memory

    Visual memoryAuditory memoryKinaesthetic memory

    Working memory

  • L Z T B W H S B

  • L Z T B W H S B

  • The furniture was highly polished

  • Common language problemsInterpretation very literal, dont understand figures of speech

    Language of mathematics 70% of dyslexics experience difficulty with number language words (sum, total, odd, take away) Chasty 1985

    Comprehension reading and oral

  • Other learning disabilities:

    Sensory Integration deficits

    Central Auditory Processing Disorder (CAPD)

    Global Learning Difficulty

  • Dyslexic or low ability?

  • Low ability profile

  • Typical dyslexic profile

  • More extreme dyslexic profile very able but indicators of dyspraxia

  • Dyslexic profile

  • Low ability profile

  • Low ability

  • Very able, but major perceptual difficulties

  • Assessment optionsSpecialist assessment centresSPELDStep by Step Centre

    Assessment software available in schools

  • Teaching methods and resourcesAll teaching needs to be:

    Highly structuredCumulativeMulti-sensory

  • Teaching needs to incorporate:

    Huge amounts of reinforcement/overlearning

    Activities to develop transfer

  • Remediation or support?In-class support v. withdrawalReader-writer/extra timeWriting or word-processing/dictating

  • Assistive TechnologyReading PenHand-held scanner (wand)Flatbed scannerDictaphone/PDALaptopSpell checker (Franklin)Tape recorder

  • Assistive SoftwareTextHelpDragon Naturally SpeakingThinksheet

  • Remedial UnitExperienced teacher v teacher aide?ComputersAdequate resourcing (including structured literacy scheme)Identify early and then blitz problems dont trickle-fee