Language Development Language Development in Children and Adolescents with Down in Children and Adolescents with Down

SyndromeSyndrome

Robin Chapman, Ph.D.Robin Chapman, Ph.D.

Waisman CenterWaisman Center

University of Wisconsin-MadisonUniversity of Wisconsin-Madison

AcknowledgementsAcknowledgements

Research supported by NIH grant R01-Research supported by NIH grant R01-HD23353 with additional support from HD23353 with additional support from the National Down Syndrome Society. the National Down Syndrome Society. We thank the participants and their We thank the participants and their parents. parents.

Thanks to Colleagues:Thanks to Colleagues:

Dr. Donna BoudreauDr. Donna Boudreau Cynthia BridgeCynthia Bridge Katherine GigsteadKatherine Gigstead Dr. Linda J. HeskethDr. Linda J. Hesketh Dr. Maura JohnsonDr. Maura Johnson Dr. Mina Johnson-Dr. Mina Johnson-

GlenbergGlenberg Dr. Elizabeth Kay-Dr. Elizabeth Kay-

Raining BirdRaining Bird Dr. Doris J. KistlerDr. Doris J. Kistler

Dr. Andrea McDuffieDr. Andrea McDuffie Dr. Sally MilesDr. Sally Miles Dr. Jon MillerDr. Jon Miller Dr. Giuliana MioloDr. Giuliana Miolo Dr. Scott E. SchwartzDr. Scott E. Schwartz Dr. Hye-Kyeung Dr. Hye-Kyeung

SeungSeung Dr. Elin ThordardottirDr. Elin Thordardottir Heidi SindbergHeidi Sindberg Dr. Nadia TeitlerDr. Nadia Teitler Dr. Laura WagnerDr. Laura Wagner

Is language acquisition modular or interactive?Is language acquisition modular or interactive? Is there a specific behavioral phenotype in Is there a specific behavioral phenotype in

children with Down syndrome?children with Down syndrome? What is the developmental trajectory of What is the developmental trajectory of

languagelanguage

skills?skills? What factors predict language production?What factors predict language production? What factors predict language comprehension?What factors predict language comprehension? What factors improve word learning?What factors improve word learning? What factors improve storytelling?What factors improve storytelling?

Questions:Questions:

Modular vs. Interactionist Modular vs. Interactionist TheoryTheory (Chapman, 2000)(Chapman, 2000)

Modular view of language predicts a Modular view of language predicts a specific language deficit in both specific language deficit in both comprehension and productioncomprehension and production

Interactionist view predicts multiple Interactionist view predicts multiple dissociations, including comprehension dissociations, including comprehension and production, arising and production, arising developmentallydevelopmentally

Developmental Emergence of Language in Down Developmental Emergence of Language in Down

Syndrome: Syndrome: Evidence for Interactionist Position (Chapman, 2004) Evidence for Interactionist Position (Chapman, 2004)

I. SOCIAL INTERACTION I. SOCIAL INTERACTION

*slower emergence of emotional affect recognition in *slower emergence of emotional affect recognition in DS (DS (spollak@wisc.eduspollak@wisc.edu) and frequent hearing ) and frequent hearing impairmentimpairment

PersonSoundsHeard

Babble

Action

Object

*

PersonSoundsHeard

Babble

Action

Object

Developmental Emergence of LanguageDevelopmental Emergence of Language

II. OBJECT INTERACTION II. OBJECT INTERACTION

*More prolonged attention to people than objects in DS

*

Developmental Emergence of LanguageDevelopmental Emergence of Language

III. III. CANONICAL BABBLING CANONICAL BABBLING

* Slower Development of Canonical Babbling, & * Slower Development of Canonical Babbling, & Frequent Hearing Impairment, in DSFrequent Hearing Impairment, in DS

PersonSoundsHeard

Babble

Action

Object

*

Developmental Emergence of LanguageDevelopmental Emergence of Language

IV. IV. JOINT ATTENTION JOINT ATTENTION

* Slower Babbling Development & Affective * Slower Babbling Development & Affective Comprehension in Down SyndromeComprehension in Down Syndrome

PersonSoundsHeard

Babble

Action

Object

*

Developmental Emergence of LanguageDevelopmental Emergence of Language

V. COMPREHENSION OF WORDS, COMMUNICATIVE INTENT V. COMPREHENSION OF WORDS, COMMUNICATIVE INTENT

* Slower Development of Communicative * Slower Development of Communicative Requesting in Down SyndromeRequesting in Down Syndrome

PersonSoundsHeard

Words

Action

Object

* *

Developmental Emergence of LanguageDevelopmental Emergence of Language VI. USE OF WORDS VI. USE OF WORDS

* Slower Development of Expressive Vocabulary * Slower Development of Expressive Vocabulary in Down Syndrome, including Signsin Down Syndrome, including Signs

PersonSoundsHeard

Words

Action

Object

**

Developmental Emergence of LanguageDevelopmental Emergence of Language VII. SIMPLE SENTENCES VII. SIMPLE SENTENCES

* Slower Development of Sentence Production in Down * Slower Development of Sentence Production in Down SyndromeSyndrome

PersonSoundsHeard

Words

Action

Object

**

***

Developmental Emergence of LanguageDevelopmental Emergence of Language VIII. COMPLEX SENTENCES VIII. COMPLEX SENTENCES

* Slower Development of Complex Syntax * Slower Development of Complex Syntax Production for Complex Events in Down Production for Complex Events in Down SyndromeSyndrome

PersonSoundsHeard

Words

Action

Object

*

* *

The phenotype in The phenotype in infancyinfancy

Learning delays accelerate at ages 2-4Learning delays accelerate at ages 2-4

Slower transition from babbling to speech; Slower transition from babbling to speech; poorer intelligibilitypoorer intelligibility

Delays relative to cognition in nonverbal Delays relative to cognition in nonverbal requesting, rate of expressive vocabulary requesting, rate of expressive vocabulary development, rate of increase in sentence development, rate of increase in sentence lengthlength

Comprehension comparable to cognitionComprehension comparable to cognition

The phenotype in The phenotype in childhoodchildhood

Selective deficits in verbal short-term Selective deficits in verbal short-term memorymemory

Longer period of phonological errors and Longer period of phonological errors and more variability; poorer intelligibilitymore variability; poorer intelligibility

Expressive language delay relative to Expressive language delay relative to comprehension and cognitioncomprehension and cognition

Grammatical morphology deficit relative to Grammatical morphology deficit relative to sentence length in productionsentence length in production

The phenotype in The phenotype in adolescence adolescence

Deficits in both working verbal memory and Deficits in both working verbal memory and visual short-term memoryvisual short-term memory

Intelligibility problems; more variability in Intelligibility problems; more variability in fundamental frequency, rate, stress placementfundamental frequency, rate, stress placement

Expressive language deficit greatest in Expressive language deficit greatest in grammatical morphemes, least in vocabulary; grammatical morphemes, least in vocabulary; MLU shows longitudinal gainMLU shows longitudinal gain

Sentence comprehension begins to lag Sentence comprehension begins to lag cognition, and shows longitudinal loss; cognition, and shows longitudinal loss; vocabulary comprehension a strength on PPVTvocabulary comprehension a strength on PPVT

The phenotype in The phenotype in young adulthoodyoung adulthood

Continuing auditory short-term memory deficitContinuing auditory short-term memory deficit

Continuing progress in intelligibilityContinuing progress in intelligibility

Continuing progress in expressive syntax: MLU Continuing progress in expressive syntax: MLU increase, complex sentence acquisitionincrease, complex sentence acquisition

Continuing strengths in size of comprehension Continuing strengths in size of comprehension vocabularyvocabulary

Loss of elaborated sentence comprehensionLoss of elaborated sentence comprehension

Predicted Predicted Comprehension Comprehension for Ages 7.5, 12.5 and for Ages 7.5, 12.5 and 17.5 17.5

Predicted Comprehension Predicted Comprehension when when Auditory ST Memory Intercept Auditory ST Memory Intercept is at is at 25%ile, mean, or 75%ile 25%ile, mean, or 75%ile

Predicted Comprehension Predicted Comprehension when when Visual S-T Memory Intercept is Visual S-T Memory Intercept is at at 25%ile, Mean, or 75%ile 25%ile, Mean, or 75%ile

Predicted MLU when SyntaxPredicted MLU when Syntax Comprehension Intercept is at Comprehension Intercept is at 25%ile, Mean or 75%ile 25%ile, Mean or 75%ile

Predicted MLU when SyntaxPredicted MLU when Syntax Comprehension slope is at Comprehension slope is at 25%ile, 25%ile, Mean or 75%ile Mean or 75%ile

Predictors of Predictors of individual individual difference: difference: For Syntax Comprehension: age, auditory For Syntax Comprehension: age, auditory

short-term memory, visual short-term short-term memory, visual short-term memorymemory

For Syntax Production (MLU): syntax For Syntax Production (MLU): syntax comprehensioncomprehension

For Grammatical morpheme comprehension For Grammatical morpheme comprehension and fast mapping of words: hearing and fast mapping of words: hearing

ImplicationsImplications

Evidence is consistent with an Evidence is consistent with an interactionist account of language interactionist account of language learning, learning,

MultipleMultiple targets for early interventiontargets for early intervention

-object play and exploration schemes-object play and exploration schemes -requesting-requesting -babbling/speech motor skills-babbling/speech motor skills

-intelligible communication (signing)-intelligible communication (signing) -affective comprehension-affective comprehension -Hearing!-Hearing!

Implications, Implications, cont’dcont’d Shifting intervention targets with Shifting intervention targets with

developmentdevelopment Need for continuing language Need for continuing language

intervention in adolescence, including intervention in adolescence, including complex syntax & literacycomplex syntax & literacy

Need to target BOTH comprehension Need to target BOTH comprehension and production, at different levelsand production, at different levels

Importance of hearing status for Importance of hearing status for intelligibility & grammatical intelligibility & grammatical morpheme comprehensionmorpheme comprehension

Evidence for specificity of Evidence for specificity of phenotypephenotype in adolescence: DS vs. CI in adolescence: DS vs. CI (Chapman, 2006)(Chapman, 2006) Comprehension deficits in DS vs. CI of unknown origin Comprehension deficits in DS vs. CI of unknown origin (nonverbal MA/CA match)(nonverbal MA/CA match)

Production deficit in DS in adolescence in interview language Production deficit in DS in adolescence in interview language samplesample

Phonological working memory plays an important role in Phonological working memory plays an important role in comprehension and production performance by both groupscomprehension and production performance by both groups

* NRT (long-term knowledge) is more important for DS* NRT (long-term knowledge) is more important for DS * digit span & visual short-term memory more important * digit span & visual short-term memory more important for CIfor CI

Hearing status affects DS grammatical morpheme Hearing status affects DS grammatical morpheme comprehension and interview-MLU comprehension and interview-MLU

Fast mapping of Fast mapping of

novel words novel words DS children & adolescents= MA matchDS children & adolescents= MA match (Chapman, (Chapman,

Kay-Raining Bird & Schwartz, 1990; Kay-Raining Bird, E., Chapman, R.S., & Schwartz, Kay-Raining Bird & Schwartz, 1990; Kay-Raining Bird, E., Chapman, R.S., & Schwartz, S.E. (2004).S.E. (2004).

With multiple words, DS=MA in comprehension but With multiple words, DS=MA in comprehension but DS<MA in production DS<MA in production (Chapman, 2003) (Chapman, 2003)

DS adolescents = syntax comprehension TD match DS adolescents = syntax comprehension TD match in using speaker intent to infer object referentin using speaker intent to infer object referent

McDuffie, A., Sindberg, H., Hesketh, L., & Chapman, R. (in press).McDuffie, A., Sindberg, H., Hesketh, L., & Chapman, R. (in press).

Repeated mention of words speeds access in Repeated mention of words speeds access in comprehension, for DScomprehension, for DS

(Chapman, Sindberg, Bridge, Gigstead, & Hesketh, 2006)(Chapman, Sindberg, Bridge, Gigstead, & Hesketh, 2006)

Narratives in Narratives in children children & adolescents & adolescents • Event content of remembered silent film: Event content of remembered silent film: DS = MA controls despite shorter MLU DS = MA controls despite shorter MLU (Boudreau & Chapman, 2000) (Boudreau & Chapman, 2000)

• Plot line & theme elements of wordless Plot line & theme elements of wordless picturebooks: picturebooks:

DS > MLU comparison group;DS > MLU comparison group; DS = syntax comprehension group DS = syntax comprehension group (Miles & Chapman, 2002)(Miles & Chapman, 2002)

• Presence (vs. absence) of picture support:Presence (vs. absence) of picture support: increases DS MLU to syntax comprehension increases DS MLU to syntax comprehension

group levelgroup level (Seung & Chapman, 2002; Miles, Chapman, & (Seung & Chapman, 2002; Miles, Chapman, &

Sindberg,2006)Sindberg,2006)

Repeated Repeated NarrativesNarratives

Repeated retellings of a wordless picture book lead to Repeated retellings of a wordless picture book lead to increases in plot line/theme expression and MLU increases in plot line/theme expression and MLU (Miles & (Miles & Chapman 2005)Chapman 2005)

Examiner scaffolding with questions yields higher MLU & Examiner scaffolding with questions yields higher MLU & improvesimproves

expression of location setting information expression of location setting information (Miles, Sindberg, (Miles, Sindberg, Bridge &Bridge &

Chapman, 2002)Chapman, 2002) and number of different words used and number of different words used (Miles (Miles 2005)2005)

Storytelling strategies Storytelling strategies (Miles, Chapman & Sindberg, 2004):(Miles, Chapman & Sindberg, 2004): -task approached as retelling of related events-task approached as retelling of related events -evaluations and character speech used by both DS & syntax -evaluations and character speech used by both DS & syntax comprehension controlscomprehension controls -use of inference increased across sessions -use of inference increased across sessions -more multiple utterances in DS group-more multiple utterances in DS group

Plot line/Theme Content of Plot line/Theme Content of Repeated Narratives, Repeated Narratives, DS vs. Syntax comprehension DS vs. Syntax comprehension matched group matched group (Miles & Chapman, (Miles & Chapman, 2005)2005)

(D = DS, T = TD)

MLU of Repeated Narratives,MLU of Repeated Narratives, DS vs. Syntax DS vs. Syntax comprehension comprehension matched group matched group (Miles & Chapman, (Miles & Chapman, 2005)2005)

Answers:Answers:

Language acquisition is interactive, emergent, Language acquisition is interactive, emergent,

non-modularnon-modular Children with Down syndrome show a Specific Children with Down syndrome show a Specific

Language Impairment Language Impairment Trajectory: MLU and complex syntax increase Trajectory: MLU and complex syntax increase

with age: No evidence of a critical periodwith age: No evidence of a critical period Trajectory: Syntax comprehension declines inTrajectory: Syntax comprehension declines in

late adolescence and young adulthoodlate adolescence and young adulthood

Answers, Answers, continuedcontinued Language comprehension Language comprehension

predicts language productionpredicts language production Auditory and visual short-term memory Auditory and visual short-term memory

predict predict

language comprehensionlanguage comprehension hearing also predictshearing also predicts

grammatical morphology & grammatical morphology & intelligibilityintelligibility

Implications forImplications for Language Language InterventionIntervention Need for language intervention in Need for language intervention in

adolescence, including literacyadolescence, including literacy Need to target both comprehension Need to target both comprehension

and production, at different levelsand production, at different levels Repeated mention of novel word in Repeated mention of novel word in

play improves speed of its play improves speed of its comprehensioncomprehension

Implications for Implications for Intervention , Intervention , cont’dcont’d Need to provide hearing support for Need to provide hearing support for

intelligibility and grammatical intelligibility and grammatical morpheme comprehension morpheme comprehension

Helpfulness of picture support for Helpfulness of picture support for narrative content & MLUnarrative content & MLU

Helpfulness of narrative practice for Helpfulness of narrative practice for MLUMLU

Methodological Methodological implications implications Comprehension AssessmentComprehension Assessment -Vocabulary: frequency vs. concept (PPVT vs TACL--Vocabulary: frequency vs. concept (PPVT vs TACL-

voc)voc) -Past use of PPVT as MA match has mismatched TD -Past use of PPVT as MA match has mismatched TD

groupsgroups and overestimated adolescent DS MAand overestimated adolescent DS MA -Syntax: differential effects of hearing on -Syntax: differential effects of hearing on

morphology & morphology & sentence structuresentence structure

Language SamplesLanguage Samples -Conversation vs. narration-Conversation vs. narration -Visual support for narration-Visual support for narration

Some Thoughts Some Thoughts about about Future Research Future Research Importance of modeling individual Importance of modeling individual

differences in studying DD differences in studying DD populationspopulations

Imaging: to illuminate short-term Imaging: to illuminate short-term memory contributionsmemory contributions

Genome variation: to predict IDs in Genome variation: to predict IDs in longitudinal language & cognitive longitudinal language & cognitive trajectoriestrajectories

Genetic dissection of learning will Genetic dissection of learning will remap our dissection of phenotyperemap our dissection of phenotype

ReferencesReferences

Abbeduto, L. & Chapman, R.S. (2005). Language and Abbeduto, L. & Chapman, R.S. (2005). Language and communication skills in children with Down syndrome and communication skills in children with Down syndrome and Fragile x. In P. Fletcher & J. Miller, Eds., Fragile x. In P. Fletcher & J. Miller, Eds., Trends in language Trends in language acquisition research, vol 4: Developmental theory and acquisition research, vol 4: Developmental theory and language disorders. language disorders. Amsterdam, NL: John Benjamins. Amsterdam, NL: John Benjamins.

Boudreau, D. & Chapman, R.S. (2000).The relationship between Boudreau, D. & Chapman, R.S. (2000).The relationship between event representation and linguistic skill in narratives of event representation and linguistic skill in narratives of children and adolescents with Down syndrome. children and adolescents with Down syndrome. Journal of Journal of Speech, Language, and Hearing Research, 43,Speech, Language, and Hearing Research, 43, 1146-1159. 1146-1159.

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References, ctd.References, ctd.

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McDuffie, A., Sindberg, H., Hesketh, L., & Chapman, R. (in McDuffie, A., Sindberg, H., Hesketh, L., & Chapman, R. (in press). Use of speaker intent and grammatical cues in fast-press). Use of speaker intent and grammatical cues in fast-mapping by adolescents with DS. mapping by adolescents with DS. Journal of Speech, Journal of Speech, Language, and Hearing Research.Language, and Hearing Research.

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Miles, S. & Chapman, R.S. (2002). Narrative content as Miles, S. & Chapman, R.S. (2002). Narrative content as described by individuals with Down syndrome and typically described by individuals with Down syndrome and typically developing children. developing children. Journal of Speech, Language, and Journal of Speech, Language, and Hearing ResearchHearing Research, , 4545, 175-189. , 175-189.

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Miles, S., Chapman, R.S. & Sindberg, H. (2006). Sampling Miles, S., Chapman, R.S. & Sindberg, H. (2006). Sampling context affects MLU in the language of adolescents with Down context affects MLU in the language of adolescents with Down syndrome.syndrome.Journal of Speech, Language, and Hearing Research, 49Journal of Speech, Language, and Hearing Research, 49, 325-, 325-227. 227.

Miolo, G., Chapman, R.S., & Sindberg, H. (2005). Sentence Miolo, G., Chapman, R.S., & Sindberg, H. (2005). Sentence comprehension in adolescents with Down syndrome and typically comprehension in adolescents with Down syndrome and typically developing children: Role of sentence voice, visual context, and developing children: Role of sentence voice, visual context, and auditory-verbal short-term memory. auditory-verbal short-term memory. Journal of Speech, Journal of Speech, Language, and Hearing Research, 48,Language, and Hearing Research, 48, 172-188. 172-188.

Seung, H-K. & Chapman, R.S. (2000). Digit span in individuals Seung, H-K. & Chapman, R.S. (2000). Digit span in individuals with Down syndrome and typically developing children: with Down syndrome and typically developing children: Temporal aspects. Temporal aspects. Journal of Speech, Language, and Hearing Journal of Speech, Language, and Hearing ResearchResearch, , 4343, 609-620.., 609-620..

Seung, H.K., & Chapman, R. S. (2003). The effect of story Seung, H.K., & Chapman, R. S. (2003). The effect of story presentation rates on story retelling by individuals with Down presentation rates on story retelling by individuals with Down syndrome. syndrome. Applied PsycholinguisticsApplied Psycholinguistics, 24, 601-618., 24, 601-618.

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