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Executive functions. 37-975-01 Challenges to Language Acquisition: Bilingualism and Language Impairment Dr. Sharon Armon-Lotem Bar Ilan University. Domain General Accounts (Not language specific. Procedural Deficit Hypothesis (PDH) Processing limitations in Executive Functions (EF).

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Executive functions

Executive functions

37-975-01

Challenges to Language Acquisition: Bilingualism and Language Impairment

Dr. Sharon Armon-Lotem

Bar Ilan University


Domain general accounts not language specific
Domain General Accounts (Not language specific

  • Procedural Deficit Hypothesis (PDH)

  • Processing limitations in Executive Functions (EF)


Procedural deficit hypothesis pdh
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


Procedural memory system definition
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


Procedural system characteristics
Procedural System: Characteristics

  • Gradual acquisition of procedures

  • Learning occurs with practice, over time

  • Rapid, automatic application

  • “Implicit Memory System”


Procedural deficit hypothesis
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


Pdh empirical evidence
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


Pdh behavioral evidence
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


Grammatical profile of sli
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


Processing limitations in executive functions ef
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.


What are executive functions
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



Difficulties in executive function
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


Executive functions are separable but not independent
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


Executive functions

From: Profiles of Executive Function in Developmental and Acquired Disorders: Measurement and Classification, Mariëtte Huizinga, Ph.D., COST Action IS0804


Executive functions

From: Profiles of Executive Function in Developmental and Acquired Disorders: Measurement and Classification, Mariëtte Huizinga, Ph.D., COST Action IS0804


Executive functions

The activatory component or Acquired Disorders: Measurement and Classification, Mariëtte Huizinga, Ph.D., COST Action IS0804

mental attentional capacity (M capacity) is a limited

capacity to boost activation of schemes relevant for

task performance.Mcapacity 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.

Im-Bolter, N., Johnson, J., & Pascual-Leone, J. (2006). Processing limitations in children with specific language impairment: The role of executive function.

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.


Aim hypothesis p 1826
Aim & Hypothesis (p.1826) Acquired Disorders: Measurement and Classification, Mariëtte Huizinga, Ph.D., COST Action IS0804

  • “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).”


Participants
Participants Acquired Disorders: Measurement and Classification, Mariëtte Huizinga, Ph.D., COST Action IS0804


Mental attentional capacity m capacity measures and results
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<0.001, and an interaction, F(2, 174)=3.94, p<0.05, but no main effect for M measure, F(2, 174)=0.28, 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


Executive functions

  • 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.


Executive functions

  • level of language performance is directly related to the amount of M capacity that one can mobilize;

  • recentration (updating) but not decentration (shifting) is related to efficient use of processing resources with respect to language

  • 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.


Executive functions

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


Participants1
Participants ground: Part II. Nonlinguistic performance by linguistically diverse learners


Executive functions

EO=BI ground: Part II. Nonlinguistic performance by linguistically diverse learners

EO=BI

EO=BI

EO=BI

*EO<LI

*EO<LI

EO<LI

*EO<LI

BI<LI

BI<LI

BI<LI

*BI<LI

* p<0.05

Subtle inefficiency in basic non-linguistic processing of children with SLI


Executive functions

  • 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


Language proficiency and executive control in bilingual children with tld and with sli
Language Proficiency and Executive Control in Bilingual Children with TLD and with SLI

Peri Iluz-Cohen

Bar Ilan University

Ramat-Gan, Israel