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									  Bridging linguistic and neurocognitive
     approaches to the acquisition of
   morphosyntax in healthy-developing
   children and children with Specific
         Language Impairment




DOMINIK RUS                 SHAV49 Annual Conference
Department of Linguistics   Speech & Hearing Assoc.
Brain & Language Lab        of Virginia
Georgetown University
dr59@georgetown.edu         Richmond, Virginia
                            March 2, 2007
              Roadmap

(1) Intro: Language – Brief Background
(2)Biolinguistics: Basic Assumptions
(3)Language Development & the
    Acquisition of (Verb) Morphosyntax:
    Major Issues
(4)Early Verb Morphosyntax
(5) Specific Language Impairment (SLI)
(6)SLI & Verb Morphosyntax
(7) Residual Issues & Conclusion
               Language
• Levels of investigation

   Neurochemical
   Cellular
   Functional

• What is Linguistics?

• What is Language?

• Where is Language?
Language




           Miller (2003)
     The scope of biolinguistics

•   Mechanism (Structure + Function)
•   Physical basis
•   Development in an individual
•   Evolution
    (Jenkins 1997, 2004)


Mechanism (Structure + Function)
“Knowledge of language” (Chomsky 1986 ff.)

Phonology, Morphology, Syntax
Semantics, Pragmatics
     The scope of biolinguistics

Physical Basis & Evolution
•   Selection rather than instruction (cf.
    Gazzaniga 1992)

•   Exaptation rather than adaptation (Hauser et
    al. 2002, Fitch et al. 2002 vs. Pinker & Jackendoff 2005;
    Jackendoff & Pinker 2005)

Development in an individual
•   Innateness (UG) rather than emergence
    (Gazzaniga 1992; Chomsky 1981ff. vs. Bates et al. 1996;
    Goldberg 1995 ff.; Tomasello 1992 ff.)

•   Continuity (cf. Carey 1995; Crain et al. 2003)
    The scope of biolinguistics
Theories of language growth
• Describe
• Explain



The “three factors” (Chomsky 2005)
Explain

  INNATE
              EXPERIENCE     COGNITION
PRINCIPLES
                (Input)     COMPUTATION
    (UG)
        Language development

•   Skinner
•   Piaget
•   Chomsky
•   „connectionists‟
    (e.g., MacWhinney)

today: all of the above, plus
• „new connectionists‟
  (e.g., Newport)
• „new nativists‟ (e.g., Yang)
         Language development
Two broader approaches
• Internally-driven (UG) vs. (mainly)
  externally-driven ( input-driven)

Internally-driven (Crain 2003, 2005; Hyams 2003,
    2005; Wexler 1994, 1998, inter alia)
•   angle of projection continuity; „deep‟
    generalizations
•   UG; parametric differences
•   Early Morphosyntactic Convergence
    (EMC) fast
•   effortless learning w/ very few errors
•   errors due to maturation and/or
    performance factors
        Language development
Methodology

Thornton & Tesan‟s videos:
http://www.maccs.mq.edu.au/laboratories/ac
   quisition/languagevideos.htm

CHILDES:
the CHILDES database (TalkBank)
http://childes.psy.cmu.edu/
Director: Brian MacWhinney
http://psyling.psy.cmu.edu/brian/
        Language development
Externally-driven (Goldberg 1995, 2006; Tomasello
  1992, 2003, inter alia)
• input-matching; “cut-and-paste”
  approach
• slow, piecemeal acquisition of
  „constructions‟
• lots of errors & generalizations
• memorization & rote-learning; initially
  item-based, later generalizations
• order of acquisition determined
  (mainly) by frequency & saliency in
  input
• no innate predisposition (input +
  general cognition
  Adult verb morphosyntax
e.g., English present tense & past tense
                 paradigms
              Sg           Pl
    1        play      play
    2        play      play
    3        plays      play


              Sg           Pl
     1      played      played
    2       played      played
    3       played      played
    Adult verb morphosyntax
Theoretical issues

• Lexical vs. functional categories,
  labels
• Computation, features, hierarchy,
  recursion, Merge/Move, locality,
  binarity, other principles
• Here: Tense, Agreement, Aspect
• Syntax vs. morphology (feature-
  based computation vs. feature spell-
  outs)
Adult verb morphosyntax

    IP   [Inflection: T(ense) & Agr(eement)]


                                V+ -s, -ed, (Ø)
SUBJ      I
                         BE (am, is, are, was, were)
                              HAVE (have, has)
     I            VP   MODALS (can, should, will, etc.)
[+T, + Agr]                   DO (do, does, did)


              V         OBJ
agree
Early verb morphosyntax
     Early verb morphosyntax
Early English

(1) Mumma ride horsie.     (Sarah, 2;6)
                           (Guasti 2002)

(2) Papa have it.          (Eve, 1;6)
                           (Guasti 2002)


(3) Him fall down.         (Nina, 2;3)
                           (Wexler & Schütze 1996)


(4) Cowboy Jesus wear boots.     (Adam)
                           (Brown 1973)
    Early verb morphosyntax
(1) Paula play   ball.     (Paula, 1;6; Radford 1990)


(2) That my briefcase.     (Eve, 1;9; Guasti 2002)

(3) Doggie barking.        (Bethan, 1;9; Radford 1990)

•   omission of T/AGR  BARE VERB STEMS
    (BVs)/INFINITIVES in finite contexts
    (= Root/Optional Infinitives)           [1]
•   omission of Copula BE                   [2]
•   omission of Auxiliary BE                [3]
•   omission of Modals & Auxiliaries DO & HAVE
                 Approaches
   UG      FORMAL        (NEURO)
 MATUR    LINGUISTIC    COGNTIVE GEN COGN
             (FL)          (NC)


                              PROCESSING
                   UNDERSPEC    CONSTRUC
                   TRUNCATION    CONNECT
 STRUCTURAL
      (syn)       NO FUNC MAT    T or AGR
COMPARATIVE        SYNT-PRAGM     T & AGR
  (syn, morph)    TRUNCATION+
    METRIC                        Number
(morph, phon)     VARIATIONAL        Asp
                  (morph, phon)   T/Agr/Asp
  Early verb morphosyntax in
         structural FL
(a) Feature underspecification
        CP                           [+Focus/Topic/wh-]


   C         AgrP                    [+Agreement]


        Agr         TP               [+Tense]


             T           AspP        [+Perfective]


                 Asp            VP


                         V
      Language Development
What is underspecification?
•   Features are missing; syntax is present
•   Features & syntax are missing (“deletion”)
•   Features & syntax are missing (“not developed
    yet”)


What is underspecified?
•   Tense                  (Wexler 1994)
•   Tense or Agreement     (Schütze & Wexler 1999)
•   Number                 (Hoekstra & Hyams 1998)
•   Aspect                 (Gavruseva 2003)
•   Tense, Agreement & Aspect (Salustri & Hyams 2003)
       Language Development
Wexler‟s account (1998, 2000, 2002, 2007)
Deeper/conceptual issues
•   Biology is responsible for OIs/lack of
    finiteness (not “learning”)
    (“maturation”)
•   Kids know morphosyntactic properties
    of target L as early as we can test them
    (age 18 mos.)
•   Kids are “little inflection machines”
•   Stage theories assuming “learning”
    cannot explain the observed data
       Language Development

Wexler‟s account (1994, 1998, 2000, 2002, 2007)
Theoretical issues
•   UCC (Uniqueness Checking Constraint)
•   T feature is optionally missing and T
    morphemes are thus optionally omitted
•   Later (w/ Schütze): T or Agr is missing
•   Interaction btw/ Case & finiteness and
    subjecthood & finiteness
         Language Development
(b)Phrase structure truncation (Rizzi 1993/4)
           CP


     C          AgrP


          Agr          TP


                T           AspP


                Asp            VP


                       V
       Language Development
(b‟) Phrase structure truncation + (Rizzi 2005)
• Truncation but now resorting to
    interaction between UG and
    performance factors
• L development is grammatically based
    but performance-driven
• Non-target consistent properties
    observed in L development correspond
    to genuine UG options, but the factors
    determining their temporary adoption
    by the child lie in the growth of
    performance systems
         Language Development
(c)No early functional representation
   pre-functional  functional
           VP                        CP


     V                           ……
OR
                   MATURATION &/or
           AspP       LEARNING            ……
                                               VP
     Asp          VP


           V
    Predictions & Explanations
Morphological properties
•   Nonfinite morphology        [all]
•   (Early) aspectual marking   [some UNDERSPEC]
•   Morpheme order (?)          [none]
Syntactic properties
•   no INFL-material            [all]
•   no C-material               [all]
•   V placement                 [some UNDERSPEC]
Semantic properties
•   Eventivity                  [some UNDERSPEC]
•   Modal interpretation        [some UNDERSPEC]
Language Development




  10 Puzzling
  observations
#1: Early RIs cross-linguistically

(1) Mumma ride horsie.                  [English]
                           (from Guasti 2002)



(2) Kisa   finna      dúkkinni.         [Finnish]
   cat     find-inf   the-doll
                           (from Salustri & Hyams 2006)



(3) Payaso       venir.                 [Spanish]
   clown come-inf
                           (from Grinstead 1998)
     #2: High T/Agr omission
 Child     Language     Age      %BVs       Source
 Sarah                 1;8-2;3    90     Poeppel &
                                        Wexler (1993)
 Adam      English     2;3-3;0    81    Sano & Hyams
                                           (1994)

 Child Language           Age   %RIs     Source
Simone German          2;0-2;6   52 Beherens (1993)
Embla  Swedish         1;8-1;10  61  Platzack (1990)
                                     Sigurjónsdóttir
  Eva      Icelandic    1;1-2;4  65
                                     (2004)
 6 kids     Dutch      1;7-2;1   71      Blom (2003)
Nathalie    French     1;7-2;1   76     Rasetti (2000)
         #3: No (apparent) T/Agr
                  omission
 Child    Language      Age      %RIs       Source
 Denis                2;0-2;7    2.8     Leonini (2002)
           Italian                      Salustri & Hyams
Martina               2;1-2;7     0
                                        (2006)
Diana                 2;0-2;7     0
           Catalan
 Pere                 1;9-2;4    3.7    Ezeizabarrena
Maria                 1;7-2;6    1.6    (2002) after Bel
           Spanish                      (1998)
 Juan                 1;7-2;10    3
 Miki                 2;1-2;4     0
          Hungarian                      Londe (2004)
 Andi                 2;1-2;5     1
Addéla      Czech     1;9-2;4    1.5     Smolík (2002)
                                         Rus & Chandra
5 kids    Slovenian   1;5-2;0     1
                                         (2005)
  #4: Other Early Root Nonfinites
               (ERNs)
(5) Odletela.
    flown.sg.fem.perf.
    „It‟s flown away‟ (referring to a bird)
                        (Slovenian; from Rus & Chandra 2005)


(6a) Dady coming.
(6b) Him gone.
(6c) Baby do it.        (English; from Radford 1990)


(7) Pio     vavasi.
    Spiros read-perf
    „Spiros has read‟   (Greek; from Varlokosta et al. 1998)
      ERNs                   Languages
BVs             ENGLISH, INUKTITUT, K‟ICH‟E,
                NAVAJO, QUECHUA, SWAHILI,
                GERMAN
RIs (+)         All Germanic other than ENGLISH,
                FAROESE, FRENCH, HEBREW,
                RUSSIAN, SWEDISH
RIs (+)         BRAZILIAN PORTUGUESE, CZECH,
                POLISH, SPANISH
BarePresParts   ENGLISH, all Romance non-RI Ls
BarePastParts   all Romance non-RI Ls, all Slavic
                (non-RI) Ls
BarePerfectives GREEK
Imperatives     all Romance non-RI Ls, HUNGARIAN,
                all Slavic non-RI Ls
           #5: ERNs not categorical

•    across Ls, w/in L


     Child  Language     Age      %RIs     Source
    Addéla             1;9-2;4     1.5   Smolík (2002)
    Martina  Czech     1;11-3;2    11    Smolík (2002)
                                   19    Moucka (1999)
                                          Tryzna (to
     Kasia    Polish   1;5-1;9     14
                                            appear)
                                           Poeppel&
     Eve               2;3-3;2     97
             English                     Wexler (1993)
     Tom               1;11-2;5    43     Bel (1997)
         #6: Morpheme order

         Spontaneous production                  Elicit.
                                                 (imit.)
        BV
-ing    -ing       -ing     -ing       -ing     -ing
-ed     -ed        -ed      -ed        -ed      -ed/-s
-s      -s         -s       -s         -s       -ed/-s
Leopold Menyuk     Brown    De         James    Brown &
(1949)  (1969)     (1973)   Villiers   &        Frazier
                            (1973)     Kahn     (1963)
                                       (1982)

Confirmed by language modeling in Babel (Kazman 1991,
1994, 1999) for early English and Polish: Asp>T>Agr
     No Freq effects in the acq of
     grammatical morphemes 1/2
r = .133 (Eve), r= .521 (Adam), r= .349 (Sarah)
(from Cheng 2004)
No Freq effects in the acq of
grammatical morphemes 2/2
              #7: Gradualness
(adapted from Hulit & Howard 2006)                  English
Morpheme                             Age Range of Mastery
Present Progressive (-ing)           19-28 mos.
Irregular Past Tense                 25-46 mos.
Regular Past Tense (-ed)             26-48 mos.
Regular 3sg (-s)                     26-46 mos.
Irregular 3sg (e.g., “has”)          28-50 mos.

                              Age      %RIs       %Fin Vs
 Simone (German)              2;0       72          28
 (Clahsen & Penke             2;6       32          68
       1992)                  3;0       16          84
                              4;0       4           96
         #8: Hidden errors/ERNs

adapted from Aguado-Orea & Pine (2004, 2005)

 Child     Lang       Age         n        RIs     %
                                                 Error
 Lucía    Spanish    2;2-2-7    1,681      0.5    4.5
 Juan               1;10-2;5    3,098      2.4    4.4

BUT…
                                 Aguado-Orea & Pine (2005)
(8a) Yo      va?
     I       go.3sg.pres
    (Maren – 2;3, Radford & Polennig-Pacheco 1995)

(8b) Yo      quiere              hacerlo.
     I       want.3sg.pres       do.inf-it
    (Eduardo – 3;0, Grinstead 1998)

Cf. Davidson & Goldrick (2003); Davidiak & Grinstead (2004);
Rus (2006)
Suppliance of 3s pres


               Spanish
               Bel (1998)


               Slovenian
               Rus (2006)




               Czech
               Smolík (2002)
    #9: Syntax before morphology
Placement (but generally no/wrong morph)
•  V placement (for reviews, see Wexler 1994 and Lardiere
    2007)
•   Position of (reflex & pron) clitics
    (for reviews, see Guasti 2002 and Stiasny 2006)
•   Syntactic “placeholders” (e.g., Stromswold 1990;
    Crago & Allen 1996; Dye et al. 2004; Dye 2005)


Feature Mismatch (right F, wrong Form)
(10) Da    iser grosser           fisch.
     there is-he big              fish
     „There is a big fish‟         (Clahsen & Penke 1992)
(cf. Lardiere & Schwartz 1997; Lardiere 2000)
               #10: Role of input




from Aguado-Orea & Pine (2005)
 Juan‟s sample:
 quiero    (want.1s pres) 53.7% of all V tokens
 puedo     (can.1s pres)     10.8%
 tengo     (have.1s pres) 8.2%
 pongo     (put.1s pres)     4.4%
  75% of all Vs are highly frequent Vs

Agr in child Slovenian IMPs (Rus & Chandra (2006)

 Total #     679                        other
  IMPs                                  21%


                              get off

AGR corr.   673/679            1%

                               give
            (99.1%)            13%              look
                                                65%

            All 2SG
The errors grow as most frequent Vs are systematically
excluded from the count (in 1s, 2s, 3pl, BUT NOT for
3s!)
The lessons learned
Other Factors???




  O‟Grady et al. (1997)
Utterance-final position: Dutch Infs
Wijnen et al (2001)
•   Frequency
•   Utterance-final (“peripheral) position
•   Semantic transparency

       Lang            % [-T] utterances in
                       sent-final position
     Spanish                    26
     German                   65
      Dutch                   82
                      Freudenthal et al. (2005)
Freudenthal et al. (2005)
AGR errors in pres T Vs       (Rus 2006)




AGR errors in IMPs     (Rus & Chandra 2006)
•   3 incomplete stems (w/ stressed syllables)
•   3 3sg pres ind forms
    Language development cont.
•   Neurolinguistic accounts
    Hierarchy of difficulty w/ respect to
    functional projections (e.g., Friedmann &
    Grodzinsky 1997; Hagiwara 1995)


•   Inflectional Hierarchy Hypothesis
    (IHH) (cf. Izvorski & Ullman 1999)
•   For agrammatic anterior aphasics:
    V > Pres & Past Part (Asp) > T > Agr
•   “Deficit”: more Merge = more computation =
    more difficulty
•   True for development and additional support
    from L modeling
        Language development
A lesson from language modeling (Kazman
    1991a,b)
•   Computational modeling of English
    morphemes (“Babel”)
•   Same results as Brown (1973) and deVilliers‟
    (1973) for English
•   Reports similar results for early Polish
    (confirming Smoczynska 1985)

                               Brown de Villiers‟ Babel
    Present Progressive (-ing) 1          2             1
    Past Regular (-ed)         7          7             7
    3rd Person Regular (-s)    8          8             7
             Solution?
“Mother Nature meets Momma Nurture”
(Rus 2006)



              +
        Variability Model of
       Morphosyntactic Learning
•   Hierarchy of difficulty w/ respect to
    functional projections (e.g., Friedmann &
    Grodzinsky 1997; Hagiwara 1995)


•   Inflectional Hierarchy Hypothesis
    (IHH) (cf. Izvorski & Ullman 1999)
•   for agrammatic anterior aphasics:
    V > Pres & Past Part (Asp) > T > Agr
•   “Deficit”: more Merge = more computation =
    more difficulty
•   true for development and additional support
    from L modeling
       Variability Model of
      Morphosyntactic Learning
 CP
                               IHH as morph-
  AgrP (+ Pers)
                               syntax mapping

Agr       TP                   V Competition
                               Hypothesis
      T        AspP

           Asp AgrP (-Pers)    VBV/3s > VInf
               Agr        VP

                      V
         Variability Model of
        Morphosyntactic Learning
Predictions
•   Syntax before morph
•   Surface morph consistent w/ the IHH
•   If pers/num = Ø  potentially ERN
    (“default) ( errors!)
•   Infs/BVs (=”3s”) competition
•   (-Pers) before (+Pers) agreement
•   Not all-or-nothing

(a) Not all affixes may be in place –
    Segmentation & Learning of exceptions
    (Peters 1982; Pinker 1984, 1999; Blom & Wijnen submitted)
(b) Frequency effects (Aguado-Orea & Pine 2004, 2005)
(c) Cognitive effects??? (Behrens 2001)
          Future Research
“A Case for biology”? YES, but…




                 Miller (2003)
            Language development

Why is interdisciplinary approach difficult?
Different levels of abstraction & granularity

Granularity Mismatch Problem (GMP)
(Poeppel & Embick 2005, Poeppel 2007)


•   Linguistic vs. neuroscientific studies of L
    operating w/ objects of different granularity

•   Linguistic computation involves a number of fine-
    grained distinctions and explicit computational
    operations whereas neuroscientific approaches to L
    operate in terms of broader conceptual distinctions
        Language development
GMP cont.
Fundamental elements of representation (at a
given analytic level)

LINGUISTICS            NEUROSCIENCE
distinctive feature    dendrites, spines
syllable               neuron
morpheme               cell-assembly/ensemble
noun phrase            population
clause                 cortical column
         Language development
GMP cont.
Fundamental operations on primitives (at a
given analytic level)

LINGUISTICS             NEUROSCIENCE
Concatenation           Long-term
                        potentiation (LTP)
Linearization           Receptive field
Phrase-structure        Oscillation
generation
Semantic composition    Synchronization
                           SLI
SLI: Quick facts
Disorder: significant limitation in L ability w/ no apparent
  factors that accompany L learning problems (e.g.,
  hearing impairment, low nonverbal intelligence,
  neurological damage) (Leonard 1998)
Onset: at birth
Peak: infanthood & childhood; continues into adulthood
  in a minority of cases (BUT careful testing reveals
  disruptive linguistic knowledge even w/ older adults;
  Leonard 1998)
Prevalence: about 7% (Leonard 1998; Tomblin 1996: 7.4%)
  [“pure SLI” probably much less”; Tower (1979): 1.5%;
  American Psychiatric Association: 5% for production;
  3% production + comprehension]
Sex differences: apparently more prevalent in males (usu
  3:1) (Leonard 1998; Tallal et al. 1989, 2001)
Role of genetics: SLI children more likely to have parents
  and siblings w/ a history of language learning problems
                                      SLI
Areas considered before SLI applies
       FACTOR                           CRITERION
Language ability        Language test scores of -1.25 SD or lower; at risk
                        for social devalue
Nonverbal IQ            Performance IQ of 85 or higher
Hearing                 Pass screening at conventional levels
Otitis media effusion   No recent episodes
Neurological            No evidence of seizure disorders, cerebral palsy,
Dysfunction             brain lesions; not under medication for control of
                        seizures
Oral structure          No structural anomalies
Oral motor function     Pass screening using developmentally
                        appropriate items
Physical and social     No symptoms of impaired reciprocal social
interactions            interaction or restriction of activities
                                                         (Leonard 1998: 10)
                           SLI
Interaction btw/ an adult and an SLI child:

Adult:       This is Jim. Tell me a story about Jim.
Child:       Him going fishing. Jim hold…water.
             And go fish. And [unclear] /…/
Adult:       Ok. How many more do you think we
             have?
Child:       I don‟t know. /…/
Adult:       This is Kathy. Tell me a story.
Child:       Kathy brush teeth. Her eat. And he get
             clothes on.
Adult:       She must be getting ready to go to
             school, right?

(Leonard, Bartolini, Caselli, McGregor & Sabaddini 1992)
                                SLI
PROBLEMS
(a) SLI subsumed under language
    impairment (LI)
(b) Different nature of deficit

(c) Mainly physicians (bias?)

(d) Aphasia/dysphasia – inappropriate term


SLI vs. other LI types
(a) Subtypes of children w/ LIs, possibly also w/in SLI
(cf. van der Lely 1996, 2005)
(b) Overlap w/ deficit motoric in nature
(c) LIs: children who comprehend only single words
vs. complete inability to comprehend L
                     SLI
Terminology: Issues to consider

•   Clinical vs. non-clinical (e.g.,
    educational/research world approach to
    a study of developmental disorders)

•   Expressive vs. receptive vs. expressive
    and receptive disorder

•   “Specificity”

•   “Language”
                           SLI
“Specific language impairment is a condition in which
  language is impaired but other cognitive functions
  are normal.” (Guasti 2002: 376, emphasis mine)

“Children with this condition demonstrate a delayed
  emergence of grammar at the same time that
  prerequisite levels of hearing acuity, general cogntive
  ability, and social development meet normative
  expectations.” (Rice & Wexler 1995: 451, emphasis mine)

“SLI children are characterized by severe problems in
  the development of language comprehension and
  expression but do not have an impairment in
  nonlinguistic cognitive or motor development,
  hearing, or emotional-social behavior…” (van der Lely
  1996; partly citing Benton 1964, emphasis mine)
                             SLI
“I do not claim that Grammatical SLI is,
   necessarily, an autonomous sub-group from all
   other SLI sub-groups, but I propose that the
   Grammatical SLI children are homogeneous
   within the sub-group.” (van der Lely 1996: 189,
   emphasis mine)

  …although poor sensory or non-verbal abilities
  often co-occur with SLI, there is no evidence that
  these impairments cause the grammatical
  deficits found in SLI. Moreover, evidence
  suggests that impairment in at least one
  subgroup is specific to grammar.” (van der Lely
  2005: 53, emphasis mine)
                          SLI
“There are some serious flaws in the argument presented
  by van der Lely and Howard (1993) that children with
  specific language impairment do not have deficits in
  verbal short-term memory, despite earlier evidence that
  they do (Gathercole & Baddeley 1990).” (Gathercole &
  Baddeley 1994, emphasis mine)

“Specific Language Impairment in Children is Not Due to a
  Short-Term Memory Deficit: Response to Gathercole &
  Baddeley” (van der Lely & Howard 1994)

…despite the standard use of exclusionary criteria to
 diagnose SLI, the disorder is clearly not limited to
 language.” (Ullman & Pierpont 2005: 399, emphasis mine)

POTENTIAL MISINTERPRETATION: cause vs.
  comorbidity
                    SLI
Why study SLI?
• clinical concerns (intervention)
• educational concerns (assistance;
  special programs, etc.)
• providing a type of baseline of LI
• theories of language

•   “knowledge of L”
•   acquisition/development
•   L organization (domain-specificity;
    modularity; compensation; critical
    periods; maturation)
                      SLI
Methodology

L tests…do not do justice to SLI children‟s
language problems (Muma 1986), but are a
good starting point in the diagnostic
procedure

different modalities (comprehension vs.
production); different areas/domains of L;
serve only as the starting point; different
criteria modality- & score-wise; MLU
(morphemes – norm: Miller & Chapman 1981;
words – norm: Templin 1957)
      SLI & Verb Morphosyntax
Usual methodology
• 2 control groups: age-matched + L matched
  (=MLU-matched)
• Usual lag of 2 years (e.g., SLI5, N5, N3: 5 year-
  old SLI kids vs. 5 year-old normals matched on
  age + 3 year-old MLU-matched normals)
• Spontaneous speech + probe (elicitation tasks)


Example of PROBES:
This is Mary. She sings. /…/ What did she do
yesterday?
Every day I spling around London. Just like every
day, yesterday I _________around London
(van der Lely & Ullman 1996)
    SLI & Verb Morphosyntax
SLI: Common linguistic features
“IMPAIRED”
• L emerges late(r)
• L shows unexpected patterns of phonology,
  morphology, and syntax, remaining below age
  expectations
• the most affected domain - verbal inflectional
  morphology (specifically 3 SG PRES TNS –s
  and PAST TNS –ed forms)
• L impairments usually continue well into
  elementary school years and even persist into
  adulthood
    SLI & Verb Morphosyntax
“SPARED”
• pluralization of nouns (accuracy 90% and
  above, Oetting & Rice 1993) [interestingly, SLI
  subjects overregularize regular –s (*foots,
  *mans) evidence contra rote
  learning/memorization; Oetting & Rice 1993]

BUT Leonard et al. (1992): mean correct use of
 plural –s 68.6% only (WHY? Statistical
 analysis with SD: 34%?, different
 population?)

• prepositions (Rice & Wexler 1996)
• when morphemes are supplied, they show
  correct forms (features) (*She are here)
       SLI & Verb Morphosyntax
(WITHIN & ACROSS SUBJECTS)

•   not every aspect of inflectional morphology is
    equally impaired
•   areas other than inflectional morphology may be
    impaired (e.g., passive voice, etc.) (van der Lely 1996,
    1998; van der Lely & Harris 1990)
•   the acquisition of words (esp. verbs) is
    vulnerable (Rice et al. 1994; Oetting, Rice & Swank 1995)
•   word retrieval problem sometimes occurs w/ SLI
    (Leonard 1998)
•   (mild) phonological deficits can be observed in
    some subjects
•   the disorder may be receptive and/or expressive
•   in some cases language impairments disappear
    in elementary school years or not before
    adulthood
     SLI & Verb Morphosyntax
Major explanations for lack of “finiteness”
in SLI kids

•   Deficit alters local aspects of grammar
    Deficit in establishing agreement relations
    (particularly, subject-verb agreement
    relation)
•   Deficit in computing structure-dependent
    relations
•   Deficit targets only particular grammatical
    (morphosyntactic) features, such as [TNS]
    and [AGR] or [PLURAL])
•   The Surface Hypothesis
     SLI & Verb Morphosyntax
Deficit alters local aspects of grammar
(Wexler & Rice)


•   Underspecification

•   EOI (Extended Optional Infinitive)

•   Grammar is globally intact; same
    categories & principles

•   Principles are not missing or
    dysfunctional, but are biologically not
    instantiated yet/inoperative (maturation)
     SLI & Verb Morphosyntax
EOI cont.

•   Emergence from the OI stage is a
    maturational process, guided by a genetic
    program (Wexler 1992; 1994; 1996)

•   ATOM as a clinical marker for SLI

    “We are not aware of any competing models that
    can explain the interacting empirical properties
    that we have discussed, especially models that do
    not incorporate as part of their explanation the
    existence of particular grammatical principles
    and their development.” (Wexler & Schutze 1999)
     SLI & Verb Morphosyntax
Deficit in establishing agreement relations
(particularly, subject-verb agreement relation)

Predictions:
(a)  SLI children have trouble with AGR morphemes
(b) SLI children do not have trouble w/ other
     infl morphemes (Clahsen 1986, 1991; Rothweiler &
      Clahsen 1993; Clahsen, Bartke & Göllner 1997)

German-speaking SLI children are proficient in using
TNS morphemes, but not AGR morphemes (Rothweiler &
Clahsen 1993)

TNS is supplied perfectly (99% corr on lex Vs & 100%
on SEIN), but AGR is not (67% on lex Vs & 93% corr. on
SEIN) (Clahsen, Bartke & Göllner 1997)
      SLI & Verb Morphosyntax
Deficit targets only particular grammatical
   (morphosyntactic) features
•   Missing features (e.g., [+PLURAL] or [+PAST])
•   Children cannot construct implicit rules (Gopnik et
    al. 1997)
•   Children cannot see the internal structure of
    inflected words & are not able to build implicit
    rules for handling inflectional morphology (even
    regular morphology is rote-learned & stored in the
    lexicon as unanalyzed chunks (Gopnik et al. 1997)

Predictions:
•   Frequency effects for regular & irregular words
•   Difficulties w/ the inflection of novel words
•   Incorrect segmental & prosodic features of
    inflected words
    SLI & Verb Morphosyntax
SLI children
• Are bad on the wug test (usually /wags/)

•   Search for phonologically similar item w/
    novel Vs (brom-?: /branz/)

•   Generally 30-50% correct on regular infl
    morphology (rote-learning, apparently)

•   Retrieval of irregular Vs subject to frequency
    effects

BUT Rice & Oetting (1993): SLI kids process
  regular & irregular plurals distinctively
    SLI & Verb Morphosyntax
Shortcomings of empirical studies

• SLI subjects of different ages
• Different methodology
• Spontaneous speech data reported
  generally from the same corpus (e.g., the
  Kansas Language Database)
• Vs not controlled for freq
• Usually no intra-subject data (i.e.,
  performance on each morpheme w/in the
  subject)
• Very few reports on all morphemes w/in the
  same data corpus
     SLI & Verb Morphosyntax
Future directions
• Neurocognitive accounts (the brain has
  been largely ignored) (Ullman & Pierpont 2005)

• Cross-linguistic evidence (part.
  morphologically complex languages)

• Bridging linguistics and
  neuropsychology/neuroscience (e.g., the
  Inflectional Hierarchy Hypothesis)
Future directions
Several factors have complicated efforts to provide a unified
theory:
      1) Disorder is not limited to language
      2) Neural bases of disorder have been largely
      ignored
      3) Disorder is highly heterogeneous
(Ullman & Pierpont 2004)


Procedural Deficit Hypothesis (PDH): SLI largely explained
by abnormalities of brain structures of the procedural
memory system (Ullman & Gopnik, 1999; Ullman & Pierpont,
2004)
Future directions
PROCEDURAL system
Brain system implicated in the learning of new, and
control of established, motor and cognitive skills,
especially those involving sequences (e.g., riding a bike)
(Ullman 2004)

• Composed of a network of brain structures:
Rooted in frontal/basal-ganglia circuits (frontal: SMA
and Broca‟s area)
• Basal ganglia: subcortical structures projecting to
frontal
Cortex in parallel channels
Also: cerebellum, inferior parietal, and superior
temporal cortex
(Schacter & Tulving, 1994; Ullman, 2004)
Future directions
• PDH: Many if not most SLI individuals are afflicted
with procedural system brain abnormalities that result
in grammatical and/or lexical retrieval deficits.

• These individuals may be characterized as having
Procedural Language Disorder (PLD).

• Such individuals should show impairments of the non-
linguistic functions that also depend on the affected
brain structures of the procedural system.


(Ullman & Pierpont 2004)
  Future directions
BUT again…

Bridging evidence
from
linguistics and
neuropsychology/ne
uroscience
THANK YOU

								
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