Embed Size (px)
Citation preview
1
HarnessingIndividualVariabilitytoImproveEducationalOutcomes:
CaseStudiesandInterventions
JoannaA.Christodoulou
MGHInstituteofHealthProfessions
2
DefiningDyslexia• What is the basis? Neurobiological in origin• What are the main features? Difficulties in accurate and/or
fluent word recognition and by poor spelling and decoding abilities
• Why? Difficulty with the sounds of language (phonology)• What else? Average or higher cognitive skills• What else? Reading comprehension, reduced reading
experience • What else can contribute to reading issues? Exclusion of
cultural, educational, environmental, or other disabilities• Can you tell from a brain scan? No
(Lyon et al., 2003)
LearningDisabilities
ReadingDisabilities
Dyslexia
ContextualizingReadingDifficulties
ReadingComprehensionImpairment
3
Whystudywhy?
Wolf, M. (2007). Proust and the Squid.
Underlyingcausewilldetermineprognosis
ManypathstoReadingDifficulty
• Decoding
• Fluency
• Strategiesforcomprehension
• Backgroundknowledge
• Multi-LanguageLearners
• Taskdemands
Goal+Learner+Context
4
Fletcher,2007
Spoken&Written LanguageRelationships
Receptive Expressive
Auditory
Visual
Listening Speaking
WritingReading
ModifiedfromDorisJohnson
5
SimpleViewofReading
• DecodingxListeningComprehension=ReadingComprehension
• Linkbetweenreadingcomprehensionanddecodingdecreaseovertime
• Linkbetweenreadingcomprehensionandlisteningcomprehensionincreaseovertime
6
PROCESSES INVOLVED IN WRITTEN LANGUAGE
Word Identification/Spelling
Orthographic Processing Phonological Processing (Letter Processing) (Sound Processing)
Attention Orthographic/Phonological Association Executive Function Visual Motor/ Memory Oral Motor
Automaticity Fluency
Comprehension/Expression
Syntax Morphology Semantics Discourse Pragmatics Literal Conversation Inferential Narrative Applied Expository
Some Other Factors Affecting Reading/Written Expression Intellectual Functioning Background Experience ESL Features of the Text Educational Opportunity Motivation/Emotional Stage of Reading Pamela Hook, Ph.D., 2010
SingleversusMultipleDeficits
• Cognitivesubtypes
• Equifinality andEquipotentiality
• Multi-variate continuum
• Relativeversusabsoluteperformance
(Pennington,2006)
7
MagnocellularCerebellar
Motor Visual
Visual-SpatialAttention
Auditory
Phonology
PhonologicalMemory
PhonologicalAwareness
RhythmicProcessing
RapidTemporalProcessing
Anchoring
PerceptualLearning
ProcessingSpeed?
NamingSpeed
RapidNaming
TheoreticalDeficitFrameworksforDyslexia
SingleWordReadingDifficulty
Level: Neuro
Level: Cognitive
Level:Behavioral
DoubleDeficitHypothesis
(Ramusetal.,2003)
DeficitProfilesAmongAdultswithDyslexia
8
Highlights• Generalreadingdifficultieshavemanycauses
• Thesignatureofspecific readingdifficultiesisthattheyare ‘unexpected�
• ThemostreadilyidentifiableSRDisdyslexia,aspecificdifficultywithphonologicalprocessing
• Sourcesofreadingcomprehensionfailurearemulti-facetedandinteractwiththetextcharacteristicsandcontextforreading
• Caveat:labelsareproductsofcultureandtime
9
The Reading Brain
(Wolf, 2007)
3CoreReadingBrainNetworks
Posterior:VentralNetwork
AnteriorNetwork
Posterior:DorsalNetwork
Motorproduction,processingunfamiliarwords
Supportsdecodingskills
Supportsword
recognition
10
CharacteristicsofDevelopmentalDyslexia
Posterior:VentralNetwork
AnteriorNetwork
Posterior:DorsalNetwork
• Relativelymoreactivationinthefrontal/anteriorsystem
• Relativelyless activationinback/posteriorsystems• Activationofsimilarregionsintherighthemisphere(Brunswick,1999,Paulesu etal.2001;Rumseyetal.,1992,1997;Shaywitz etal.,1998,2002;Simos,Breier,Fletcher,Bergman,&Papanicolaou,2000;Shaywitz etal.,2002;Simos,Papanicolaou,etal.,2000)
Intervention:Brain&BehaviorChanges
• Brainnetworksrecruitedforreadingareadaptableduringdevelopmentandmodifiableinstrugglingreaders
• Plasticityofthereadingbrainacrossreaderages
11
Task: Word repetition or sound deletion
(Eden et al., 2004)
Task: Word repetition or sound deletion
Increased activation in parietal and phonological regions
Increased frontal regions
Decreased activation in left of the occipitotemporalcortex (shift from visual to phonological strategies)
(Eden et al., 2004)
DyslexicInterventionGroup
12
NewResearch:SummerReading&StrugglingReaders
• Whatisthenatureofsummerreadingoutcomesforyoungstrugglingreaders?
• Whatistheimpactofsummerinterventionforyoungstrugglingreaders?
Collaborators:JohnGabrieli;JackMurtagh;KellyHalverson;AbigailCyr; PamelaHook; T.Guarino;PatriciaChang
SummerTimeAdventuresinReading&Teaching(STARTStudy)
• Participants:– Ages6-9
– Completinggrade1or2
• Recruitedfromcommunity
• RandomizedControlTrial(RCT)– StrugglingReaders
• InterventionGroup
• WaitingControlGroup
(Christodoulouetal.,2017)
13
SummerTimeAdventuresinReading&Teaching(STARTStudy)
• TreatmentGroup
• Instruction:4hoursx5daysx6weeks– Providedatnocost
– Minimumof100hours
– Academicsummermonths
– Groupsof3-5children
– Lindamood-Bellteachingstaff
• Program:Lindamood-BellSeeingStars
(Christodoulouetal.,2017)
SeeingStars:SymbolImageryforFluency,Orthography,SightWords,andSpelling
• Orthographicandvisualprocessingtraining,andconsequentlyphonologicaltraining
• Visualize:Letters
SyllablesWords
Connectedtext(Semanticinformation)
• Justasthestarsarepartsofthesky,lettersarepartsofwords
14
-10 -8 -6 -4 -2 0
2
4
6
8
10
12
Lindamood-BellSymbolImageryTest
UntimedWordReading(WRMTWordIdentification)
UntimedPseudowordReading(WRMTWord
Attack)
Stan
dardScoreDifferen
ce(P
ost-
Pre)
SummerSlideintheNo-TreatmentGroupSummerGlideintheTreatmentGroup
TreatmentDyslexicDifference
No-TreatmentDyslexicDifference
(Christodoulouetal.,2017)
Intervention-Difference
NoIntervention-Difference
-15
-10
-5
0
5
10
15
Chan
geScores(Po
st-Pre)
InterventionGroup
Non-InterventionGroup
InterventionEffectsExample:Schoolyearvs.Summer
TypicalInterventionStudyOutcomes
SummerStudyOutcomes
15
KeyFindings
• Directevidenceforwideningdifferencesbetweenstudentswithreadingdifficultieswhodoanddonotreceiveintensivesummerreadinginstruction
• Convergencewithstudiesofothervulnerablestudentpopulationsforsummerreadingoutcomes
(Christodoulouetal.,2017)
Implications
• Informourdefinitionofasuccessfulintervention
• Preventionofacademicsummerslide/regression
• Improvementofoutcomes
16
NewResearch:SummerReading&SES
• Howdoessocioeconomicstatusrelatetoliteracyskills&responsetosummerreadingintervention?
Collaborators:RachelRomeo(supportedbyNIH5T32DC000038);JohnGabrieli;KellyHalverson; AbigailCyr; JackMurtagh;PatriciaChang;PamelaHook
SocioeconomicStatus(SES)“Anindividual'saccesstoeconomicandsocialresources,
aswellasthebenefitsandsocialstandingthatcomefromtheseresources;oftenmeasuredbyeducationalattainment, income,and/or
occupation.”
• Strongpredictorofacademicachievementandcognitiveskillinchildhood&throughoutlife(Bradley&Corwyn,2002)
• “Achievementgap”growswithage(Lee&Burkam,2002)
• Disproportionateeffectonlanguageandliteracyskills(Nobleetal.,2005;Nobleetal.,2012)
(Romeo,Christodoulou,etal.,2017)
17
SES&ReadingDisability• Low-incomestudentshaveadisproportionatelyhigherrateofRDdiagnosis(Shifrer etal.,2010;Fluss etal.,2009)
• StudiesofSES&cognitionaretypicallyconductedon“typicallydeveloping”childrenwithscoresintheaveragerange.
• StudiesofRDaretypicallyconductedonmid-to-high-SESconveniencesamples.
50%oflow-SESchildrenreadbelowabasiclevelvs.21%ofhigher-SESchildren(NAEP,2007)
“Decreasedaccesstoresourcesmayamplifycognitiveriskfactorsforpoordecoding”(Nobleetal.,2006)
(Romeo,Christodoulou,etal.,2017)
SocioeconomicStatus&Language
• Strongpredictorofbrainstructure,withadisproportionateeffectonthecanonical“languageareas”(Raizada etal.,2008;Nobleetal.,2012)
– Todate,thesestudieshavelargelybeendonein“typically”developingreaders
(Nobleetal.,2012)
18
ReadingDisability
• Structuralbraindifferencesinclude:– Reducedgreymatterinlefttemporo-parietalcorticalregions(Hoeft etal.,2007;Richlan etal,2012)
– Reducedcerebralwhitematterinthe“readingpathway”(leftarcuatefasciculus) (Vandermosten etal.,2012)
CorticalThickness
pial surface• Shortest distance between
white and pial surfaces.• 1-5mm in healthy subjects
SlidebytheFreesurfer DevelopmentTeamatMGH
19
RelationofSEStoCorticalThicknessatPre-Test
(Romeo,Christodoulou,etal.,2017)
SummaryofResults
• DoesthebrainstructureofstudentswithreadingdisabilityvarybySES?– Yes,SESpredictsthethicknessandvolumeofareasincludingkeyreading
andlanguageregions.
– ThisextendstraditionalSESbrainstructureresultstoaclinicalpopulation(withdeficitsintheneurocognitiveareasmostaffectedbySES).
(Romeo,Christodoulou,etal.,2017)
20
DifferencesBetweenChildrenWhoRespondedMoreorLesstoIntervention
• LowerSESandlowerreadingpredictedgreaterimprovement(controllingforpre-test)
(Romeo,Christodoulou,etal.,2017)
DifferencesBetweenChildrenWhoRespondedMoreorLesstoIntervention
• Nosignificantdifferencesinthicknesschangesbetweentheinterventionandwaitingcontrolgroups,*only*withininterventiongroup
• Respondersexhibitedsignificantlygreaterthickeningthannon-responders
• Leftmiddletemporalcluster
– responders’corticesthickened (1%gain)– non-responders’corticesthinned (0.37%loss)– waitingcontrolgrouponaveragethinned(0.26%loss)
(Romeo,Christodoulou,etal.,2017)
21
SummaryofResults
• ArethereSES-relateddifferencesinchildren’sresponsetoreadinginterventionatthelevelofbehaviorand/orbrain?– Yes,morelower-SESchildrenexhibitedimprovementthanhigher-SESpeers,evenwhencontrollingforinitialscores.
– Lower-SESchildrenalsoexhibitedgreatercorticalthicknessgrowthinanauditoryprocessingareanearWernicke’sarea.
– Thissuggeststhatintensivereadinginterventionmightbeevenmoreeffectivefortheseduallyat-riskchildren(especiallyinthesummer).
(Romeo,Christodoulou,etal.,2017)
SummaryofFindings
• NoveldemonstrationthatamongagroupofchildrenwithRD,higherSESwasassociatedwiththickercortexinmultipleneocorticalregionsassociatedwithlanguageandreading
• Despitenooverallcorticaldifferencesbetweeninterventionvs non,childrenwhorespondedtointerventionexhibitedpre-to-postthickeningofcorticalareas
• Childrenfromlower-SESfamiliesandchildrenwithmoresevereRDweremorelikelytobenefitfromintervention,bothbehaviorallyandneurally.
22
PredictingReadingOutcomeswithNeuroimaging
• 25childrenwithdyslexia• 20typicalreaders
• Predictreadingovertime:age14à16.5
• fMRIRhymetask
(Hoeft et al., 2010, PNAS)
baitgate
pricemiss
PredictingReadingOutcomeswithNeuroimaging
• Neuroimaging(70-90%)vs.Behavioral(@chance,50%)
– Greateractivationattime1intherightfrontalregionpredicted
readingimprovement2.5yearslater
• MoreactivationofRightIFGattime1predictedbetterreading
outcomes
(Hoeft et al., 2010, PNAS)
23
ContributionsofNeuroscience
• Brainimagingcancurrently:– Continuetoinformourunderstandingofbrainplasticityinresponsetointervention
– Revealmechanismsunderlyingbehavioraltrajectories
– Demonstratebraincorrelatesforbehavioralchanges
• Brainimaginghasthepotentialto:– Anticipatewhowillbenefitfromwhichintervention
– Identifybehavioralandbraincharacteristicspredictingresponsetointervention
ParticipantsandtheirfamiliesNationalInstitutesofHealth/NationalInstituteofChildHealthandHuman
DevelopmentFacultyResearchFellowship,MGHInstituteofHealthProfessions
ThePeterandElizabethC.TowerFoundationGeorgeE.BurchFellowship,SmithsonianInstitutionWilliamF.MiltonFund,HarvardMedicalSchool
PrivateDonors
Acknowledgements
Contact:[email protected]
24
Wherecanyoulearnmore?
• BEAMwebsite:www.mghihp.edu/BEAM
• http://scholar.harvard.edu/joanna/pages/resources
• InternationalDyslexiaAssociation:www.eida.org
• MAIDABranch:www.ma.dyslexiaida.org
• www.Understood.org
JoinourresearchattheBEAMLab
• Emailus:[email protected]
• FindusonFaceBook:www.facebook.com/BEAMChristodoulou
• Enrollinourstudies:http://bit.ly/BEAMstudies
