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Executive functions 37-975-01 Challenges to Language Acquisition: Bilingualism and Language Impairment Dr. Sharon Armon-Lotem Bar Ilan University.

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Presentation on theme: "Executive functions 37-975-01 Challenges to Language Acquisition: Bilingualism and Language Impairment Dr. Sharon Armon-Lotem Bar Ilan University."— Presentation transcript:

1 Executive functions 37-975-01 Challenges to Language Acquisition: Bilingualism and Language Impairment Dr. Sharon Armon-Lotem Bar Ilan University

2 Domain General Accounts (Not language specific Procedural Deficit Hypothesis (PDH) Processing limitations in Executive Functions (EF)

3 Procedural Deficit Hypothesis (PDH) Ullman, M.T. & Pierpont, E.I. 2005. Specific Language Impairment is not Specific to Language: The Procedural Deficit Hypothesis. Cortex 41, 399-433. "SLI can be largely explained by the abnormal development of brain structures that constitute the procedural memory system.” Procedural memory: “mental grammar”, syntax, some morphology Declarative memory: “mental lexicon”, vocabulary, idioms, irregular past-tense forms

4 Procedural Memory System: Definition Brain system involved in “procedural memory”  Learning new and controlling established motor and cognitive skills, habits, and other procedures E.g. typing, riding a bike, skilled game playing  Aspects of rule-learning  Learning and performing skills involving sequences Includes system involved in learning, representation, and use of procedural memory

5 Procedural System: Characteristics Gradual acquisition of procedures Learning occurs with practice, over time Rapid, automatic application “Implicit Memory System”

6 Procedural Deficit Hypothesis Problems with different structures in the PS will result in different types of impairment Grammatical and lexical retrieval deficits are strongly linked to dysfunctions of the basal ganglia (BG), esp. caudate nucleus, and of the frontal cortex, esp. Broca’s area

7 PDH: Empirical Evidence Studies of neural correlates of SLI  Anatomical studies SLI linked to abnormalities of frontal cortex and basal ganglia SLI linked to abnormal cerebellar structures Atypical asymmetry and other abnormalities of declarative system could reflect connectivity or compensation  Event-related potential studies SLI show atypical ERPs when presented with function words, but not content words Function words elicit ERPs similar to content words, consistent with declarative system compensation

8 PDH: Behavioral Evidence Predictions of PDH  Impairment in rule-governed operations  No impairment in memorized idiosyncratic knowledge (lexicon)  Possible compensation for grammatical/procedural deficit with increased reliance on lexical/declarative memory

9 Grammatical Profile of SLI Compensatory shift between PS and DS  People with SLI use declarative memory to memorize complex forms and/or explicit rules Disproportionate reliance on high-frequency phrases No difference between regular and irregular past- tense forms Impairment in production of past-tense forms, but not judgment

10 Processing limitations in Executive Functions (EF) Im-Bolter, N., Johnson, J., & Pascual-Leone, J. (2006). Processing limitations in children with specific language impairment: The role of executive function. Child Development, 6, 1822- 1841. Kohnert, K., & Windsor, J. (2004). The search for common ground: Part II. Nonlinguistic performance by linguistically diverse learners. Journal of Speech, Language, and Hearing Research, 47, 891-903.

11 What are Executive Functions? Goal-oriented, efficient, and adaptive social behavior. Capacity to think ahead, suppress impulses,temporarily hold information, and think flexibly. Needed in carrying out a task that is complicatedor novel, requiring sustained conscious attention (Miller & Cohen, 2001). Essential in everyday behavior From: Profiles of Executive Function in Developmental and Acquired Disorders: Measurement and Classification, Mariëtte Huizinga, Ph.D., COST Action IS0804

12 Where does it happen?

13 Difficulties in executive function Decision making Planning Cognitive flexibility Inhibition “Monitoring” of one’s own behavior From: Profiles of Executive Function in Developmental and Acquired Disorders: Measurement and Classification, Mariëtte Huizinga, Ph.D., COST Action IS0804

14 Executive functions are separable (but not independent) Three ‘core’ executive functions (Miyake et al. 2000): Updating and monitoring of working memoryrepresentations; Shifting between tasks or mental sets; Inhibition of dominant or pre-potent responses. From: Profiles of Executive Function in Developmental and Acquired Disorders: Measurement and Classification, Mariëtte Huizinga, Ph.D., COST Action IS0804

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17 Im-Bolter, N., Johnson, J., & Pascual-Leone, J. (2006). Processing limitations in children with specific language impairment: The role of executive function. The activatory component or mental attentional capacity (M capacity) is a limited capacity to boost activation of schemes relevant for task performance.Mca pacity is measured in terms of the maximal number of mental schemesFnot directly activated by the here-and-now situationFthat a person can actively hold in mind (i.e., within mental attention) at any one time. M capacity - Mental attentional capacity. The maximal number of mental schemes, not directly activated by the here-and-now situation, that a person can actively hold in mind at any one time.

18 Aim & Hypothesis (p.1826) “To investigate M capacity and executive function in children with and without SLI to determine whether children with SLI have a general processing deficit or deficits in certain executive processes, and the extent to which these processes are related to language competence”. “To examine whether potential impairments in general executive processes mediated the relationship between activatory (M) and inhibitory (I) processing resources and language competence”. “If children with SLI truly have limited processing capacity that is domain general, compared with their chronological age peers, they should perform at a lower stage on all M-measures, regardless of specific domain (i.e., visual vs. verbal).”

19 Participants

20 Mental Attentional Capacity (M capacity) - Measures and results A 2 X 3 (M measure) ANOVA with repeated measures on the second factor indicated a main effect for group, F(1, 87)=63.67, p 0.50. A 2 X 3 (MAM subtest) ANOVA with repeated measures on the second factor results in main effects for group, F(1, 87)=40.82, p<0.0001, and MAM subtest, F(2, 174)=250.97, p<0.0001, but no interaction, F(2, 174)=0.76, p>0.45. Performance for all children decreased as interference increased

21 The SLI group had lower scores on all three M measures compared with the NL group. The SLI group performed at a similar level across all three M measures. >> children with SLI have limited processing capacity that is domain general rather than domain specific. The strength of the group effect was greater for the language/verbal M measures, however, and this suggests that there may be some domain-specific factors (e.g., linguistic executives) that affect verbal processing to a greater degree. The SLI group performed more poorly than the NL group on tasks of updating and inhibition The two groups did not differ on tasks of shifting, however.

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23 (a) level of language performance is directly related to the amount of M capacity that one can mobilize; (b) recentration (updating) but not decentration (shifting) is related to efficient use of processing resources with respect to language (c) interruption (inhibition) does not have a direct relationship with language competence, but may be related to language performance via its dialectical relationship with M capacity. These results provide evidence for the hypothesis that deficits in updating and inhibition ability affect efficient use of resources for activating relevant information in language tasks.

24 Kohnert, K., & Windsor, J. (2004). The search for common ground: Part II. Nonlinguistic performance by linguistically diverse learners

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26 Participants AgeN 10;7 (1;10)50EO 10;6 (1;7)26LI 9;9 (1;5)22BI

27 *EO<LI EO<LI BI<LI *BI<LIBI<LI EO=BI *EO<LI * p<0.05 Subtle inefficiency in basic non-linguistic processing of children with SLI

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29 Bialystok, E., & Martin, M. (2004). Attention and inhibition in bilingual children: Evidence from the dimensional change card sort task. Developmental Science, 7, 325-339. HEBA 10/1 Prior, A., & MacWhinney, B. (2010). A bilingual advantage in task-switching. Bilingualism: Language and Cognition, 00(0), 1-10. DANIEL 10/1

30 Language Proficiency and Executive Control in Bilingual Children with TLD and with SLI Peri Iluz-Cohen Bar Ilan University Ramat-Gan, Israel


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