specific language impairment (sli) - introduction

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Specific Language Impairment (SLI) - Introduction 37-924-01 Theoretical Approaches to Specific Language Impairment (SLI) Dr. Sharon Armon-Lotem Bar Ilan University

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Specific Language Impairment (SLI) - Introduction. 37-924-01 Theoretical Approaches to Specific Language Impairment (SLI) Dr. Sharon Armon-Lotem Bar Ilan University. Clip. SLI - Definition. - PowerPoint PPT Presentation

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Page 1: Specific Language Impairment (SLI) - Introduction

Specific Language Impairment (SLI) - Introduction

37-924-01

Theoretical Approaches to Specific Language Impairment (SLI)

Dr. Sharon Armon-LotemBar Ilan University

Page 2: Specific Language Impairment (SLI) - Introduction

Clip

Page 3: Specific Language Impairment (SLI) - Introduction

SLI - Definition

A developmental language disorder characterized by Gleason (2001, p. 504) as involving ‘delayed or deviant language development in a child who exhibits no cognitive, neurological or social impairment’. Children with SLI show impaired language development from birth (with problems which may either disappear during childhood or persist into adulthood) with no hearing loss (no history of otitis media), no emotional and behavioral problems, no below average non-verbal IQ(>=85), no neurological problems, and no oral or facial defects (Tallal & Stark 1981). That is, they are normal in other aspects of their physical, mental and social development (Radford 2006).

Page 4: Specific Language Impairment (SLI) - Introduction

SLI impact on child’s social world

Normative children (NC) prefer talking to other NC rather than SLI children even at preschool level

SLI children prefer to talk with adults SLI children have difficulty performing basic

social tasks (e.g., accessing ongoing interaction) 8-12 year old SLI were rated by teachers as

being less cooperative and less assertive; have fewer peer contact in school environment; and were less satisfied with peer social relationships

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Sample 1

Page 6: Specific Language Impairment (SLI) - Introduction

Sample 2

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Major Issues

Frequency of SLI Genetic basis of SLI Neurological basis of SLI Overall characteristics of SLI

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Frequency

In 5 year olds, SLI affects about 2 children in every classroom (about 7%).

It is more common in boys than girls.

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Genetic basis of SLI

http://www.youtube.com/watch?v=cnlGvcDIiHw

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Neurological basis of SLI

Hugdahl et al. 2004. fMRI Brain Activation in a Finnish Family With Specific Language Impairment Compared With a Normal Control Group. Journal of Speech, Language, and Hearing Research Vol.47 162-172

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From abstract

Functional magnetic resonance imaging (fMRI) was used to monitor changes in neuronal activation in temporal and frontal lobe areas

5 Finnish family members with specific language impairment (SLI) and 6 individuals in an intact control group.

Magnetic resonance (MR) image acquisitions were made while the participants listened to series of isolated vowel sounds, pseudowords, and real words.

The results showed significant differences between the family with SLI and the

intact control group with regard to brain activation in areas in the temporal and frontal lobes.

Temporal lobe activation differences were most pronounced in the middle temporal gyrus bordering the superior temporal sulcus. The control participants

also activated an area in the inferior frontal lobe in BA 44. Individuals with SLI showed reduced activation in brain areas that are critical

for speech processing and phonological awareness. The present functional brain imaging data fit well with other recent imaging data

that also showed structural abnormalities in the same and neighboring areas.

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Sentences produced by children with SLI (Radford 2006)Sentences produced by the SLI children in the Leonard files on the childes data-base.

No Child Child utterance Adult counterpart 1 B Maybe goes on this one Maybe it goes on this one 2 B What say? What did you/d’you say? 3 C Can get us some them? Can you get us some of them? 4 C Do this come out? Does this come out? 5 C Billy wanna has his blocks out Billy wants to have his blocks out 6 C The tree must broken off The tree must have broken off 7 D Superman have him hands up Superman has his hands up 8 D And they’re jump in water And they’re jumping in the water 9 D This is mine daddy’s This is my daddy’s 10 D I will be Chad brother I will be Chad’s brother 11 D Them is boys They are boys 12 D Me don’t know how do it I don’t know how to do it 13 E How you knowed? How did you know? 14 F It cames off It came off 15 G I didn’t sawed you come in I didn’t see you come in 16 G Think her too growed up I think she’s too grown up 17 H What is this is? What is this? 18 H What next one is? What’s the next one?| 19 J Hope him gonna hit him butt I hope he’s gonna hit his butt 20 K Me no like him I don’t like him

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Expressive vs. receptive deficit

SLI children typically show some (or all) of the following types of impairment:

Phonological (e.g. problems with consonant clusters and syllable-final consonants)

Lexical (delayed acquisition of words – e.g. first word appears around 23 months in SLI children, but around 11 months in TD children; SLI children also have word-finding problems)

Semantic (problems in determining the linguistic meaning of words, phrases and sentences, and understanding the meaning of metaphors)

Grammatical (e.g. problems with affixes/inflections and articles/particles, complex syntax)

Pragmatic (e.g. problems in the use of language in appropriate contexts) Reading problems

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Delay versus Deviance

Delay: Protracted acquisition of language, following typical developmental pattern.

Deviance: Different developmental sequences and processes.

Delay Plateau Profile differences Abnormal frequency of errors Qualitative difference

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SLI – Accounts: Competence vs. performance

37-924-01

Theoretical Approaches to Specific Language Impairment (SLI)

Dr. Sharon Armon-LotemBar Ilan University

Page 16: Specific Language Impairment (SLI) - Introduction

Possible accounts

Competence or performance? Impairment in the language mechanism

vs. impairment in language processing aptitude?

Impairment in language processing vs. impairment in processing?

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Domain General Accounts (Not language specific)

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Auditory (temporal processing) deficit hypothesis

Merzenich, M. Jenkins, W., Johnston, P., S., Schreiner, C., Miller, S. L. & Tallal, P., (1996) Temporal Processing Deficits of Language-Learning Impaired Children Ameliorated by Training, Science, v. 271, p. 77-81. (=Fast ForWord)

Task: discriminate between speech stimuli -six syllable contrasts ([ba] versus [da], [da] versus [ta], [ε] versus [ae], [dab] versus [daeb], [sa] versus [sta] and [sa] versus [sha]).

Findings: LI group made most errors discriminating syllables which were

differentiated by consonants and fewest errors on those differentiated by vowels.

The LI group was significantly poorer than the normal in discriminating all syllables that incorporated brief temporal cues followed rapidly in succession by other acoustic cues.

They also were impaired in discriminating [sa] versus [sha]. They were unimpaired discriminating stimuli differentiated by vowels.

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Perceptual Deficit Model

Leonard, L. B.1989. Language learnability and specific language impairment in children. Applied Psycholinguistics 10: 179-202

Following the sonority scale (Srlkirk 1984), Leonard proposes that SLI is an Auditory Perceptual Deficit: Vowels and diphthongs are easier to perceive than consonants

(and consonants are particularly difficult to perceive when occurring in clusters of two or more successive consonants)

Stressed vowels are easier to perceive than unstressed vowels, long vowels and diphthongs are easier than short vowels, and full vowels are easier than reduced vowels

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Percentage correct probes and spontaneous speech (Rice & Wexler 1995)

SLI N3 N5 -ed probe 27 45 92 -ed spontaneous 23 46 90 -s probe 22 44 91 -s spontaneous 37 60 89 BE probe 50 64 95 BE spontaneous 46 71 96 DO probe 30 47 90 plural 88 96 97 Prepositions 96 97 98

What would be the predictions for Hebrew?

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SLI in Hebrew monolinguals Dromi et al. (1993, 1999)

Predictions: With verbal morphology so central in Hebrew, a Semitic language, it was predicted that a very few inflections, if any, would pose a problem for

children with SLI. inflections which carry more features would be more

difficult than those which carry fewer features with errors that show a simpler feature complex.

Method: Hebrew speaking children with SLI, ages 4-6, using a sentence completion task and enactments.

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Findings Sentence completion: while monolingual children with TLD

scored at ceiling, children with SLI showed 80% success when one feature was involved, but hardly ever produce the target morpheme which represented two features (fem. pl.).

Enactment: while monolingual children with TLD scored at ceiling, children with SLI showed 80% success when one feature was involved, but only 60% success when two features (person and gender) were involved.

While in English most errors are omissions, in Hebrew most errors are substitutions in which a morpheme which marks just one feature was used to replace a morpheme which marks two features

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Verb inflection in Hebrew (Dromi 1999 et al) - present tense agreement items

0%

20%

40%

60%

80%

100%

Fem sing Masc plur Fem plur

SLI TLD - MLU

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Verb inflections in Hebrew - A comparison between the SR and Dromi et al's enactment task

0%

20%

40%

60%

80%

100%

1sg 2sg ms 2sg fm

Enactment task (Dromi et al., 1999) SR

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0 2 4 6 8 10 12 14

2sg ms

2sg fm

Figure 2 - Person errors in the past tenes

1sg 2sg ms 2sg fm 3rd sg 1 pl 2pl

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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

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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

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PROCEDURAL SYSTEM: CHARACTERISTICS

Gradual acquisition of procedures

Learning occurs with practice, over time

Rapid, automatic application

“Implicit Memory System”

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a network of interconnected structures rooted in frontal/basal-ganglia circuits, subserves the learning and execution of motor and cognitive skills.

recent evidence implicates that this system is important for specific aspects of grammar

a significant proportion of individuals with SLI suffer from abnormalities of this brain network, leading to impairments of the linguistic and non-linguistic functions that depend on it

grammatical and lexical retrieval deficits are strongly linked to dysfunctions of the basal ganglia (BG), and of the frontal cortex, esp. Broca’s area

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Domain (Language (Grammar)) Specific Accounts

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Feature Deficit Model

Gopnik, M. 1990. Feature blindness: A case study. Language Acquisition 1: 139-164

Due to a genetic deficit SLI children do not have grammatical (syntactic-semantic) features in their grammar. This is a global deficit.

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Bilingual SLI sample - English

1. *EXP: what’s Maugli doing?2. *YON: walking in in near the trees.3. *EXP: here is a… panther4. *YON: have a doll.5. *EXP: the panther has a … you are right … but the panther has a…6. *YON: a doll7. *EXP: and what’s the panther doing?8. *YON: looking for the wolves.9. *EXP: and then, what is Maugli doing now?10. *YON: playing on stairs. 11. *EXP: what’s he playing with?12. *YON: bears and coconuts.13. *EXP: what’s he doing with the coconuts? 14. *YON: try to get it. 15. *EXP: and who else do we have?16. *YON: a a a tiger and a snake.17. *EXP: oh oh. what’s the panther doing?18. *YON: ask where the kid is. 19. *EXP: you think he is asking them where the kid is.

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20. *EXP: but then what happened to the panther?

21. *YON: asleep.

22. *EXP: and when he was asleep?

23. *YON: he run away.

24. *EXP: he ran away.

25. *EXP: who found him?

26. *YON: the monkeys.

27. *EXP: oh gosh, what are they doing to Maugli?

28. *YON: picking him up.

29. *YON: then they’re almost holding.

30. *EXP: what did he do with these?

31. *YON: throwed him.

32. *EXP: he threw them?

33. *EXP: what are they these?

34. *YON: bananas.

35. *EXP: who eats the bananas?

36. *YON: monkeys.

Page 34: Specific Language Impairment (SLI) - Introduction

37. *YON: the tiger.

38. *EXP: do you think they’re friends?

39. *YON: no.

40. *YON: he plans fire.

41. *EXP: he put fire on him.

42. *EXP: and is he scared?

43. *YON: yeah.

44. *EXP: yeah so what’s he doing?

45. *YON: running away.

46. *EXP: oh gosh he’s running away.

47. *EXP: then he found a girl playing by the water.

48. *YON: yeah.

49. *EXP: and where’s he?

50. *YON: in a tree.

51. *EXP: yeah.

52. *EXP: and now…?

53. *YON: going together.

54. *EXP: they’re going together to…?

55. *YON: the house.

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Rule Deficit Model

Gopnik M & Crago MB. 1991. Familial aggregation of a developmental disorder. Cognition 39: 1-50

Studying three generations of a family in London, Gopnik & Cargo concluded that they have the same syntactic abilities as MLU matched controls, but could not generate morphological rules (due to genetic failure of the dual mechanism of morphological acquisition).

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Bishop (1994) - A study of 12 SLI children ranging in age from 8;2 to 12;11

Took it off (in reply to ‘What did they do with the top part of the pram?’)

It take me a long time (in reply to ‘Did it take you a long time to get better?)

And then Mummy taked to the garage to xxx He falled in (in reply to ‘What did Andrew do when

the ice gave way?’) He sawed mine brother (in reply to ‘Has the doctor

ever been to see you?’) The car has broked down

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Agreement Deficit Model Clahsen H, Bartke S and Göllner S. 1997. Formal features in impaired grammars: a comparison of English and German SLI children. Journal of Neurolinguistics 10: 151-171

Findings: Past tense - 76% of main verbs and 89% of auxiliaries 3Sg present tense - 49% of main verbs and 35% of auxiliaries

SLI children have problems with acquiring uninterpretable features, which make no contribution to the meaning of the sentence (semantically redundant), e.g., agreement features.

>> Tsimpli and Stavrakaki (1999) and Tsimpli (2001) - Uninterpretable Feature Deficit Model

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Contexts for 3rd person auxiliaries in the corpus of Clahsen, Bartke and Göllner (from Radford 2006) -

how do these examples support their claim?Contexts where adults would use a third person singular present form of the progressive auxiliary be

22. And boy picking ’em up (JW 11;03)

23. He jumping over a gate (WL 11;05).

24. Apples fallen out on the boy who pinching them (JW 11;03)

25. The man taking the cat down on the ground (AZ11 12;03)

26. The dog taking slipper off him (AZ11 12;03)

27. Her hugging it (CT 13;11)

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Contexts where adults would use a third person singular present form of the perfect auxiliary have

35. She sometimes buy stuff and then paint it what haven’t got coat of paint on it (RJ 11;11)

36. He been tied on (AZ12 13;0)

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Contexts where adults would use a third person singular present form of the tense auxiliary do

37. He don’t know (JW 10;3)

38. He don’t get hungry (JW 10;03)

39. What, when he don’t go to work? (JW 10;03)

40. And the bus don’t take no notice (AZ11 10;3)

41. And he don’t know how to (RJ 10;11)

42. He don’t know how to put his brakes on (AZ12 11;0)

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Agreement-and-Tense-Omission Model (Extended Optional Infinitives)

Wexler K, Schütze C & Rice M (1998) ‘Subject case in children with SLI and unaffected controls: Evidence for the Agr/Tns Omission Model’, Language Acquisition 7: 317-344

TD children omit either TNS or AGR or neither up to the age of 3. In SLI children this is extended until the age of 7-8.

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Schutze & Wexler (1996): AGR/TNS omission model (ATOM)

Finite Non-finite Nominative Subject + (he goes) + (he go) Non-Nom Subject - (him goes) + (him go)

•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?”)

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a) AGR or TNS or both may be deletedb) AGR assigns NOM. If no AGR, subject gets default casec) Default case in English is ACCd) 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.

+TNS -TNS +AGR + (he goes) + (he go) -AGR + (him go) + (go)

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Agreement-and-Tense-Omission Model (Extended Optional Infinitives)

6:3אורית רותי: פעם אחת....1.הילד אכל והילדה אכלה ואמא שטפה את הכלים והחתול 2.

הוא ישן. את קם וראהופתאום שאמא שטפה את הכלים החתולה 3.

רצה לאכול את הדבורה.הואהדבורה ו הלך לאכול את הדבורה והדבורה באואחרי זה החתולה4.

אחריו. רץכי החתולהוהם שטפו את החתולה במים באמבטיה.5.ואחר כך [טעם על המילה "אחר"] הם שמו לחתולה 6.

אה.... (רותי: סרט).

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6:7דודי רותי: פעם אחת....1. ילד וילדה אוכליםהיה2. דבורההיהו3.ואז החתול הלך לדבורה4.ופתאום החתול הלך על המרק5.את החתול באמבטיה מנקות ואמא והילד והילדה הם6.והם שמו לחתול סרט.7.

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Is the sensitivity of the tense and agreement unique to SLI?

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Agrammatism - Fridemann & Grodzinsky (1997)"This paper discusses the description of agrammatic

production focusing on the verbal inflectional morphology. Agrammatism in Hebrew is investigated through an experiment with a patient who displays a highly selective impairment: agreement inflection is completely intact, but tense inflection, use of copula, and embedded structures are severely impaired. A retrospective examination of the literature shows that our findings are corroborated by others. A selective account of the agrammatic production deficiency is proposed, according to which only a subclass of the functional syntactic categories is impaired in this syndrome. The consequence of this deficit is the pruning of the syntactic phrase marker of agrammatic patients, which impairs performance from the impaired node and higher. These findings also bear upon central issues in linguistic theories, particularly that of Pollock (1989), regarding split inflection."

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(1) ha’ish roce levashel, az hu lokeax sir ve bishel.the-man wants to-cook, so he takes(3sg-M-pr.) pot and cooked(3sg-Mpast)

(2) axshav ata holex. etmol ata telex.Now you(2sg-M) go(2sg-M-pr.). Yesterday you will-go(2sg-M-fut.)

(3) Maxar dani haya ba-yamTomorrow Danny was in-the-sea

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Is SLI only about tense and agreement?

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Scheaffer at al 2003 In children with SLI (14 Subjects: 3;11-4;10),

pragmatic principles develop normally as a function of age, rather than as a function of grammar developmental stage.

Grammatically, 4-year old children with SLI make errors comparable to younger normally developing children.

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Mabel L. Rice, Kenneth Wexler, & Jennifer Francois (2001)

Passive Comprehension: Identification of Agent

0

0.15

0.3

0.45

0.6

0.75

0.9

SLI Lexically Matched Age Matched

Per

cen

t C

orre

ct

At 5 years of age, children in the SLI group were below age peers in their comprehension of reversible full verbal passives, and similar to their younger lexically-equivalent peers

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Van der Lely HKJ and Battell J (2003)(a) Who Miss Scarlett saw somebody? (Response to ‘Miss

Scarlet saw someone in the lounge. Ask me who’ – the target response being Who did Miss Scarlet see in the lounge?)

(b) Which Reverend Green open a door? (Response to ‘Reverend Green opened a door. Ask me which one’ – the target response being Which door did Rev. Green open?).

(c) What did Colonel Mustard had something in his pocket? (Response to ‘Something was in Colonel Mustard’s pocket. Ask me what’ – the target response being What was in Colonel Mustard’s pocket?).

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Sample narrative (MoSLI)

אכלו ואכלואמא הכינה לילדים שלה אוכל ואח"כ בא לו זבוב.

אח"כ הוא כעס לה בייגלה בזנבשמו אח"כ לה בשערות משהו חםשמו אח"כ. אותה וזהוניקו אח"כ

Mom prepared food for her children and pro ate.pl and pro ate.pl Then, came a fly .

Then, he was angryThen, pro put.pl a pretzel on her tail.

Then, pro put.pl something hot in her hairThen, pro cleaned.pl her and that’s it

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Representational Deficit For Dependent Relations (RDDR)

Van der Lely HKJ and Battell J (2003) ‘Wh-movement in children with grammatical SLI: A test of the RDDR hypothesis’, Language 79: 153-181

"SLI children have problems in handling non-local dependencies (between pairs of constituents which are not immediately adjacent) such as those involved in tense marking (which involves a T-V dependency both in the agreement-based analysis of Adger 2003 and in the Affix Hopping analysis of Radford 2004), agreement (which involves a subject-verb dependency), determining pronominal reference (which involves a pronoun-antecedent dependency), and movement (which involves a dependency between two constituents, one of which attracts the other)."

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Deficit in Computational Grammatical Complexity (CGC) Marinis, T. & van der Lely, H. K. J. (2007).

On-line processing of wh-questions in children with G-SLI and typically developing children. International Journal of Language & Communication Disorders 42(5), 557-582.

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“The CGC Hypothesis claims that the core deficit in some but not all forms of SLI is in the representation and/or mechanisms underlying the construction of hierarchical grammatical structures. For G-SLI children their grammar is characterized by Grammatical Structural Economy in syntax, morphology and for most phonology too. Thus, the least complex structure will surface. Within the syntactic component, the core deficit is in computing syntactic dependencies between constituents. Within Chomsky’s Minimalist Program (Chomsky 1995), this can be implemented as optionality of the operation Move, which is not ‘automatic’ and ‘compulsory’. Further, complexity is defined as the number of movement operations, thus subject questions are predicted to be less problematic than object questions because the former has one less movement operation (van der Lely and Battell 2003). van der Lely and colleagues demonstrated that the CGC hypothesis accounts for a wide range of phenomena in English G-SLI children”

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Is it only about the functional system?

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Deficits were found for: Lexical access NWR SR Narratives Executive functions