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First steps in Language Acquisition: Evidence from ERPs. Angela D. Friederici. Max Planck Institute for Human Cognitive and Brain Sciences Leipzig, Germany. Method of Event Related Potential (ERP). • High temporal resolution as it measures the brain‘s activity millisecond by millisecond.

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slide1

First steps in Language Acquisition: Evidence from ERPs

Angela D. Friederici

Max Planck Institute for Human Cognitive and Brain Sciences

Leipzig, Germany

slide2

Method of Event Related Potential (ERP)

• High temporal resolution

as it measures the brain‘s activity millisecond by millisecond.

• No behavioral reaction necessary.

erp method
ERP method

ERP method

ONGOING EEG

Amplifier

S

S

S

S

one sec

AUDITORY EVENT-RELATED POTENTIAL

-6 µV

N400

Signal

averager

ELAN

AUDITORY

STIMULUS

(S)

P600

P200

+6 µV

200

400

600

800

1000

STIMULUS

ONSET

Time (ms)

slide4

Infants\' first Steps into Language are Based on Prosodic Information

Theidentification of word boundaries(word onset and offset) is eased by information about word stress. In a language like English or German, in which the stress of two syllable words lies predominantly on the first syllable, stress information can certainly help to identify word onsets.

Theidentification of syntactic phrase boundariesis eased by prosodic information as each intonational phrase boundary is a syntactic phrase boundary.

slide5

Syllable Length and Word Stress Discrimination

• Word stress in German is predominantly (› 90% of two syllable words) on the first syllable.

• Word stress is indicated by a number of acoustic parameters with syllable duration (length) being the most prominent one.

• In order to investigate the infants\' ability to discriminate words stressed on the first syllable versus words stressed on the second syllable we decided to initially investigate the infants\' ability to discriminate between a long and a short syllable. We did so by using the MMN paradigm.

slide6

dev

sta

sta

sta

sta

sta

Mismatch Negativity (MMN)

... is a pre-attentive response.

... is elicited by any discriminable

change in repetitive auditory stimulation (oddball design):

... is the result of deviance detection.

slide7

Experiment 1Discrimination of Syllables of Different Duration

/ba:/ 341 ms

/ba/ 202 ms

Standard 5/6

Deviant 1/6

1. Block baa baa baa baa ba baa baa baa ba ...

2. Block ba ba ba ba baa ba ba ba baa ba ba ...

slide8

250406_130306_ba_long.fh11

The Mismatch Negativity MMN

Adults: Difference wave between Deviant-Standard

Source: Friedrich, Weber & Friederici, Psychophysiology, 2004

slide9

CUNY_2006: 2411_ba_long.fh11

Experiment 1Discrimination of Syllables of Different Duration

ERP and difference waves (Deviant-Standard)

of 2-month-old infants

Source: Friederici, Friedrich & Weber, NeuroReport, 2002

slide10

2203_CUNY_2006: 130306_ba_long.fh11

0705_Trieste_2006: 250406_130306_ba_long.fh11

Experiment 1Discrimination of Syllables of Different Duration

Difference waves for long syllable in 2-month-

old infants and adults

Source: Friederici et al., NeuroReport, 2002; Friederici et al., 2004

slide11

Summary Experiment 1

• Infants by the age of 2 months are able to discriminate long syllables from short syllables.

• Infants more easily discriminate a long syllable in a stream of short syllables than vice versa.

• Infants show a positivity as MMN response.

slide12

Hypothesis for SLI

One of the hypotheses we persued was the notion that a major underlying cause of Specific Language Impairment (SLI) is a deficiency in processing prosodic information.

If so, infants with risk for SLI may be deficient already in discriminating long from short syllables at the age of 2 months.

slide13

0705_Trieste_2006: folie_16.fh11

Experiment 1b

Difference waves for 2-month-olds with and without risk for SLI

Source: Friedrich, Weber & Friederici, Psychophysiology, 2004

slide14

Summary Experiment 1b

Infants with risk for SLI differ from those with no risk already at the age of 2 months in their perceptual ERP parameters for duration discrimination.

slide15

Block baaba baaba baaba babaa baaba baaba

  • Block babaa babaa babaa babaa baaba babaa

Experiment 2Discrimination of Different Stress Patterns

/ba:ba/ 750 ms

/baba:/ 750 ms

Standard 5/6

Deviant 1/6

slide16

MMN

Experiment 2Discrimination of Different Stress Patterns

Difference waves

4- and 5-month-old infants

Source: Weber, Hahne, Friedrich & Friederici, Cognitive Brain Research, 2004

slide17

Summary Experiment 2

• Infants by the age of 5 months are able to discriminate word stress of two syllable words.

• Discrimination is evident as indicated by MMN for the trochaic pattern (stress on first syllable) which is the predominant pattern in German.

slide18

2203_CUNY_2006: alle_Folie21_weber.fh11

MMN

Experiment 2bDiscrimination of Different Stress Patterns

Difference waves

5-month-old infants

Source: Weber, Hahne, Friedrich & Friederici, Cognitive Brain Research, 2004

slide19

Summary Experiment 2b

Infants with risk for SLI demonstrate a reduced discrimination ability for the language-specific trochaic pattern at the age of 5 months.

slide20

2203_CUNY_2006: alle_Folie23_weber.fh11

MMN

Stress Pattern DiscriminationNovel Analysis: 5-month-olds

At-risk group classification based on word production at 2 years.

Source: Weber, Hahne, Friedrich & Friederici, Cognitive Brain Research, 2004

slide21

Processing Intonational Phrase Boundaries

As each intonational phrase boundary is a syntactic phrase boundary, the identification of an intonational phrase boundary provides an easy entrance into the syntax of a given language.

How can we investigate this identification process using ERPs?

slide22

Experiment 3

Prosodically correct conditions

(A) correct: Late Closure

[IP1 Peter verspricht Anna zu ARBEITEN ] # [IP2 und ...

(\'Peter promises Anna to work and ...

(B) correct: Early Closure

[IP1 Peter verspricht ] # [IP2 ANNA zu entlasten][IP3 und ...

(\'Peter promises to support Anna and ...

Source: Steinhauer, Alter & Friederici, Nature Neuroscience, 1999

slide23

2203_CUNY_2006: PhraseBoundary.fh11

Effect of Intonational Phrase Boundary

Spoken sentences: Adults

Source: Steinhauer, Alter & Friederici, Nature Neuroscience, 1999

slide24

2203_CUNY_2006: PhraseBoundary.fh11

Spoken Sentences: 8-month-old Infants

Source: Pannekamp, Weber & Friederici, NeuroReport, in press

slide25

2203_CUNY_2006: PhraseBoundary.fh11

Summary Experiment 3

Infants by the age of 8 months show a brain response to intonational phrase boundary similar to that of adults.

adults

8-month-old infants

slide26

basic mechanisms underlying the identification of intonational (syntactic) boundaries

sensitivity to intonational phrase boundary

CPS

Development of Prosodic Perception

basic mechanisms underlying the identification of word boundaries

discrimination of syllable duration

discrimination word stress pattern

2

5

8

Birth

Months of age

ERP- correlates

MMN

Source: Friederici, Trends in Cognitive Sciences, 2005

slide27

Processing Lexical-Semantic Information

To understand mechanisms of early word learning, it is important to know whether the infant’s brain acts in an adult-like manner when processing meaningful words in meaningful contexts.

The N400, a negative component in the ERP of adults, reflects neural mechanisms of semantic integration into context.

slide28

Experiment 4: Lexical-Semantic Processing

In the present study, we investigated whether the neural mechanisms observed for adults are already working during early language acquisition when infants know only a few words.

slide29

Experiment 4: Lexical-Semantic Processing

Using a picture-word design we recorded the ERP response of 12-, 14- and 19-month-old infants on slowly spoken basic level words. While infants were looking at sequentially presented pictures they were acoustically presented with words that were either congruous or incongruous to the picture contents.

slide30

Lexical-Semantic Processing Paradigm

“Ente” (duck)

congruous

“Ball” (ball)

incongruous

incongruous

“Lampe” (lamp)

“Schaf” (sheep)

congruous

time

slide31

2203_CUNY_2006: 130306_100106_fig4ausTiCS.fh11

Adults

Adapted from Friederici,Trends in Cognitive Sciences, 2005

slide32

0705_Trieste_2006: 2607_IASCL-Berlin_2005: 19month_Exper4.fh11

N400

Experiment 4: Lexical-Semantic Processing

ERP of 19-month-old infants

Source: Friedrich & Friederici, Journal of Cognitive Neuroscience, 2004

slide33

Experiment 4: Lexical-Semantic Processing

ERP of 19-month-old infants: normals and at risk

(low scores on word & sentence production)

Normals

At risk

Source: Friedrich & Friederici, Psychophysiology, 2005

slide34

2203_CUNY_2006: 100106_fig4ausTiCS.fh11

19-month-olds

Adults

Adapted from Friederici,Trends in Cognitive Sciences, 2005

slide35

2203_CUNY_2006: 100106_fig4ausTiCS.fh11

14-month-olds

19-month-olds

Adults

Adapted from Friederici,Trends in Cognitive Sciences, 2005

slide36

2203_CUNY_2006: 100106_fig4ausTiCS.fh11

12-month-olds

14-month-olds

19-month-olds

Adults

Adapted from Friederici,Trends in Cognitive Sciences, 2005

slide37

2511_fig4ausTiCS.fh11

bildwort3d.ppt (Maren)

12-month-olds

14-month-olds

19-month-olds

400 – 700 ms

400 – 700 ms

400 – 700 ms

slide38

Con_inc_12_mo_no_fam_risk

early neg.

early neg.

Experiment 4: Lexical-Semantic Processing

ERP of 12-month-old infants

Source: Friedrich & Friederici, Journal of Cognitive Neuroscience, 2005

slide39

Summary Experiment 4

Lexical-Semantic Processing

Early starting ERP differences in the infants’ temporal brain region have previously been linked to processing differences between known and unknown words (Mills et al., 1993).

• In our study, developmental changes in the early time range reflect increased familiarity with the presented words. The early negativity for congruous words in 12-month-old infants is interpreted as facilitation of phonological processing by lexical priming.

• The later centro-parietal negativity for incongruous words in 14- and 19-month-old infants is regarded as infant N400.

slide40

Conclusion Experiment 4

The occurrence of a phonological-lexical priming effect in both age groups implies that not only 14-, but also 12-month-old infants already create lexical expectations from picture contents. This result suggests the existence of some lexical-semantic knowledge even in 12-month-old infants. Infants at that age, however, do not display a N400 semantic incongruity effect that is present in

14-month-old infants. From that we conclude that N400 maturates during the first half of the second year of life.

slide41

Lexical

processing

Lexical

form

Lexical

semantics

12

14

N400

Development of Auditory Language PerceptionBasic stages and ERP correlates

Identification of intonational boundaries

Identification of word

boundaries

Developmental stages

Discrimination

word stress

pattern

Sensitivity to

intonational

phrase boundary

Discrimination

of phonemes

2

3

6

7

8

4

5

Birth

Months of age

ERP correlates

months of age

MMN

CPS

Adapted from Friederici, Trends in Cognitive Sciences, 2005

slide42

Lexical

processing

Sentence processing

Local

phrase

structure

building

Selectional

restriction

of verbs

Lexical

form

Lexical

semantics

12

14

19

32

N400

ELAN-P600

Development of Auditory Language PerceptionBasic stages and ERP correlates

Identification of intonational boundaries

Identification of word

boundaries

Developmental stages

Discrimination

word stress

pattern

Sensitivity to

intonational

phrase boundary

Discrimination

of phonemes

2

3

6

7

8

4

5

Birth

Months of age

ERP correlates

months of age

MMN

CPS

Adapted from Friederici, Trends in Cognitive Sciences, 2005

slide43

MAX

FOR

HUMAN

PLANCK

COGNITIVE AND BRAIN SCIENCES

INSTITUTE

LEIPZIG

Manuela Friedrich

Anja Hahne

Birgit Herold

Claudia Männel

Regine Oberecker

Ann Pannekamp

Christiane Weber

slide44

Experiment 5: Semantic Processes in Sentences

The next question is:

Do infants at that age also process semantic relations in sentential context?

Experiment 5 examines this question.

semantic violation
semantic violation

CZ

Semantic Violation

N400

Cz

-5

µV

correct:

"Das Baby wurde gefüttert"

"The baby was fed"

incorrect:

"Das Lineal wurde gefüttert"

5

"The ruler was fed"

0

0.5

1

sec

correct

incorrect

Source: Hahne & Friederici, Cognitive Brain Research, 2002

slide46

Stimulus Material

correct Die Katze trinkt die Milch.

The cat drinks the milk.

semantically incorrect Die Katze trinkt den Ball.

The cat drinks the ball.

Source: Friedrich & Friederici, NeuroReport, 2005

slide47

N400

Experiment 5: ERP of 24-month-olds

Source: Friedrich & Friederici, Journal of Cognitive Neuroscience, 2004

slide48

2607 Berlin IACL 2005

N400

Experiment 5: ERP of 19-month-olds

Source: Friedrich & Friederici, Journal of Cognitive Neuroscience, 2004

slide49

Conclusion Experiment 5

The data show that children at the age of 19 months can process semantic relations between words in a sentence quite similar to adults.

The N400 effect, however, is longer lasting than in adults. As the N400 is taken to reflect integration difficulties, these data suggest that integration processes take longer in young children compared to adults.

slide50

Processing Syntactic Information

In adult syntactic processing ERP studies, the ELAN has been interpreted to reflect highly automatic phrase structure building processes, whereas the P600 is taken to reflect processes of syntactic integration (e.g. Hahne & Friederici, 1999).

If so, the P600 should be present earlier than the ELAN which was shown in 6- to 13-year-old children for syntactic violations in passive sentences (Hahne, Eckstein & Friederici, 2003).

slide51

Syntactic Violation

F7

ELAN

-5

µV

correct:

"Das Hemd wurde gebügelt."

"The shirt was ironed."

5

incorrect:

0

0.5

1

sec

Pz

"Die Bluse wurde am gebügelt."

-5

µV

"The blouse was on ironed."

F7

correct

5

incorrect

PZ

0

0.5

1

sec

P600

Source: Hahne & Friederici, Cognitive Brain Research, 2002

slide52

Experiment 6: Syntactic Processing

Experiment 6 investigates at what age we can detect syntax-related ERP components. In this experiment syntactic violations were realized in simple active sentences.

slide53

Stimulus Material

correct Der Löwe brüllt.

The lion roars.

syntactically incorrect Der Löwe im brüllt.

The lion in the roars.

correct filler item Der Löwe im Zoo brüllt.

The lion in the zoo roars.

Source: Oberecker, Friedrich & Friederici, Journal of Cognitive Neuroscience, 2005

slide54

ELAN

P600

Experiment 6: Syntax adults

Source: Oberecker, Friedrich & Friederici, Journal of Cognitive Neuroscience, 2005

slide55

2411_Folie46+47.fh11

ELAN

P600

Experiment 6: Syntax 32-month-old children

Source: Oberecker, Friedrich & Friederici, Journal of Cognitive Neuroscience, 2005

slide56

0612_24month.fh11

P600

Experiment 6: Syntax 24-month-old children

Source: Oberecker & Friederici, submitted

slide57

-10

µV

s

0.8

1.6

correct

incorrect

correct

incorrect

correct

incorrect

10

24-month-old

children

32-month-old

children

Adults

ELAN

ELAN

-5

µV

-10

µV

s

s

0.8

1.6

0.8

1.6

5

10

P600

P600

P600

slide58

Conclusion Experiment 6

The data presented show for the first time that the infant‘s brain is sensitive to phrase structure violations in auditorily presented sentences already at the age of 2.5 years. Their ERP pattern reflects initial processes of structure building (ELAN) as well as late processes of syntactic integration difficulty (P600).

slide59

Experiment 7: Syntax 32-month-olds at risk

Source: Oberecker & Friederici, in preparation

slide60

Leipzig240206 & Leipzig GK II Ok 2005

-10

µV

s

0.8

1.6

correct

incorrect

correct

incorrect

correct

incorrect

10

No risk

24-month-olds

No risk

32-month-olds

Risk

32-month-olds

ELAN

µV

-15

-10

µV

s

s

0.8

1.6

0.8

1.6

15

10

P600

P600

slide61

Conclusion Experiment 7

Children with risk for SLI do not demonstrate an ELAN-P600 pattern at the age of 32 months.

This suggests that children classified at risk for SLI are delayed in their syntactic processing abilities, not only with respect to initial on-line syntactic structure building, but also with respect to late processes of syntactic integration.

slide62

Processing Phonotactically legal and illegal Pseudowords

ERP of 19-month-old infants: normals and at risk

(low scores on word & sentence production)

Normals

At risk

Source: Friedrich & Friederici, Psychophysiology, 2005

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