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Tense as a clinical marker for SLI. 37-975-01 Challenges to Language Acquisition: Bilingualism and Language Impairment Dr. Sharon Armon-Lotem Bar Ilan University. The phenomenon.
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Tense as a clinical marker for SLI 37-975-01 Challenges to Language Acquisition: Bilingualism and Language Impairment Dr. Sharon Armon-Lotem Bar Ilan University
The phenomenon • Up to the age of three children use the infinitival form of the verbs in indicative matrix clauses in 50% of their verbal utterances in English (Wexler 1994), and to a lesser extent in other languages (Armon-Lotem 1996a, Hyams 1995, Rhee & Wexler 1995, Rizzi 1994a). • Finite sentences are produced at the same time • Children seem to know the grammatical properties of finiteness and non-finiteness (e.g., Deprez & Pierce 1994)
1) a. It only write on the pad b. He bite me c. My finger hurts 2) M: ma at osa? what you do 'what are you doing ? L: tapuaxlishtot(Lior 1;08) apple to-drink 'I drink an apple'
Infinitival forms constitute only 5% of the Italian data. >>> Extensive use of root infinitives correlates with non-null subject languages. • “A language goes through an OI stage if and only if the language isnotan INFL-licensed null-subject language.” (Wexler 1996(
Some of the possible accounts • Finite and non-finite forms are used randomly • Wexler (1994), Harris & Wexler (1996): Children optionally omit tense. The use of root infinitives relates to a defective Tense that has not matured yet. • Rizzi (1994a,b): the use of root infinitives relates to children’s lack of knowledge of the functions of C (e.g. C=ROOT). Truncated trees are not available once CP becomes obligatory both in matrix and embedded contexts • Schutze & Wexler (1996): AGR/TNS omission model (ATOM) - children omit either TNS or AGR or neither • Wexler (1998): Children assume the unique checking hypothesis – The features of a DP can only check against one functional category.
Wexler (1994) • There is a correlation between the use of root infinitives and the use of bare negation. “A child who is optionally “dropping” 3rd [person] singular, will have medial negative sentences [of type I] in which the s does not appear on the verb“ (Wexler, 1994: 331): • Type I: Mary not play baseball • Type II: * Mary not plays baseball. >>> When negation precedes the verb, the verb should not be inflected.
Harris & Wexler (1996) • Bare negation used at the optional infinitive-stage are largely (over 90%) of type I. This proportion is larger than the share of root infinitives. (Table 5) • Do is omitted optionally where required for the same reason that -s is omitted optionally where required. Nevertheless, do-support is used more than Tense in general. (Table 11) • Tensed forms are used almost completely correctly. (Tables 8 & 9) • The bare stem is used both in present (64%) and non present (47%) contexts. (Table 12)
Schutze & Wexler (1996): AGR/TNS omission model (ATOM) • Non-nominative case on subjects used at the optional infinitive-stage will be largely with non-finite verbs • Only 5% of finite verbs take a non-nominative subjects, whereas 46% of non-finite verbs take a non-nominative subject. • Non-nominative is the default case. (Test: “Who wants ice-cream?”)
a) AGR or TNS or both may be deleted b) AGR assigns NOM. If no AGR, subject gets default case c) Default case in English is ACC • AGR checks 3rd person singular morphology Him goes is not attested because there is a contradiction between the verb morphology and the case on the subject.
Armon-Lotem (1996) for Hebrew • There’s a gradual increase in the use of inflected verbs. • Past tense morphology is acquired prior to person morphology, but this does not correlate with a decrease in the use of root infinitives, but rather with a decrease in the use of “stem-like forms”. • The use of root infinitives reduces (from 5% to less than 1%) only when questions (and subordination) are mastered (last stage of Klima & Bellugi 1966).
Extended optional infinitive in English (Rice & Wexler 1995) • Morphemes checked: 3rd person –s, past tense –ed, copula & auxiliary BE, and DO. • Procedure: natural language samples + probe procedure aimed at elicitation (playing with toys). • Subjects: SLI, N3 (language matched by MLU), N5 (age matched)
Children in the SLI group showed a lower level of use in obligatory context than children in either control groups. • N5 used the morphemes over 90% of the times, while SLI used them in 25%-48% of the time. • N3 where in between (45%-70%) • Error of use are very rare (SLI accuracy of agreement for probe data is like N3: 94% with BE, 82% with DO) • Other morphemes, e.g., plural, are almost at normal level • Prepositions are intact >> Tense marking is optional for a protracted period of time
Inflections in Hebrew speaking children with SLI • Dromi, E. & S. Davidson. 2002. A Clinical Marker for HSLI: from Empirical Findings to Theorizing. Paper presented at Brain and Language: Language Acquisition in Special Populations, Bar Ilan University, June. • Dromi, E., Leonard, L., Adam, G. & Zadunaisky-Ehrlich, S. 1999. Verb Agreement Morphology in Hebrew-Speaking Children with Specific Language Impairment. Journal of Speech, Language and Hearing Research, 42, 1414-1431. • Dromi, E., Leonard, L.B., & Adam, G. 1997. Evaluating the morphological abilities of Hebrew- speaking children with SLI. Amsterdam Series in Child language Development, 6, 65-78, • Dromi, E., L. B. Leonard, and M. Shteiman (1993) The grammatical morphology of Hebrew-speaking children with Specific Language Impairment: some competing hypotheses. Journal of Speech and Hearing Research 36: 760-771
The morphological richness hypothesis • SLI children have a limited processing capacity. They focus on the most salient aspects of the language they acquire. For example, in English they focus on word-order and ignore the morphology, while in German they focus on morphology and ignore the word order. • Subjects: SLI, NDA, NDL (matched by MLU)
Dromi, E., L. B. Leonard, and M. Shteiman (1993) • Findings: “Hebrew speaking children with SLI resembled their MLU controls in their use of both present and past tense inflections requiring agreement with the subject”. • In the nominal system, plural formation, adjectival agreement, and the use of the accusative case marker are all delayed, but not different from language matched controls. >>> SLI is a delay
Dromi, E., Leonard, L., Adam, G. & Zadunaisky-Ehrlich, S. (1999) Method: • Sentence completion for 3rd person. Enactment tasks for 1st and 2nd person. • 4 conjugations: pa'al, piel, hitpael, hif'il. The inflectional paradigm for past and present.
Findings • In present tense, both SLI and NDL used past for preset • In present tense, both SLI and NDL used masculine for feminine in singular and plural. • SLI found Hitpa'el more difficult – using p'iel instead. Simplifying consonants cluster. • SLI found Hif'il more difficult – using present for past and vice versa, using infinitives. • SLI found pi'el more difficult – they used also stripped forms • In past tense, 3rd person singular replaced many of the inflected forms. • SLI used it mostly instead of other singular forms (56/64) – mostly for 2nd person • NDL used it mostly instead of plural forms. • Past tense does pose a problem for Hebrew speaking SLI children, whereas difficulties with present tense are less pronounced. • Most errors were mostly related to the use of tense (60/144)) or person (67/144), but usually not both. • Most errors were different by one feature from the target (77% in the past tense) >>> A limited processing capacity, since more complex structures, which place more demands on the system, seem to be more impaired.
Blass A. 2000. Method: Spontaneous speech samples of the same children Findings: • No difference between SLI and NDL in the level of inflections • No difference between SLI and NDL in the mastery of inflections • Out of all forms in Pa’al (80% of verbs), 90% were tensed. • SLI used more bare (stripped) forms – significant, but the numbers are small. • SLI and NDL had similar errors, but SLI had more. • In natural settings children do what they know and avoid the difficult forms. >>>Delay
Davidson, S. 2002. The Language Profile of Hebrew Speaking Preschoolers with Specific Language Impairement. M.A. Thesis, TAU. Methodology: H-IPSyn Findings: SLI are similar to NDL but for three criteria: • Lexicon - SLI use a smaller variety of verb types than NDL • Mrpho-syntax - SLI make more errors than NDL but of the same kind • Pragmatic (??)- SLI have difficulties with reference not found in the NDL group
Passive Participle vs. Regular Past Tense Laurence B. Leonard, Patricia Deevy, Carol A. Miller, Leila Rauf, Monique Charest, and Robert Kurtz. 2003. Surface Forms and Grammatical Functions: Past Tense and Passive Participle Use by Children with Specific Language Impairment. Journal of Speech, Language, and Hearing Research Vol.46 43-55 The girl pushed the boy. The boy got pushed by the girl. • EOI account: different • The surface account: same
Method Subjects • 12 of the children (aged from 4,6 to 6, 10) with SLI • 12 ND-A • 12 ND-MLU Sentence completion tasks: • the use of past tense verb forms • the use of passive participle verb forms
Summary • The inconsistency with which children with SLI produce past –ed cannot be due to the surface property of this inflection. Its grammatical function probably plays the central role. • Children with SLI have special problems with verb morphology, even when tense is not involved. The passive participle –ed proved to be one such area of weakness.