Unified Model

A Unified Model for L1 and L2

Brian MacWhinney

HKIEd, Carnegie Mellon

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Thanks to ...

• Elizabeth Bates Michèle Kail Kerry Kilborn• Csaba Pléh Klaus Köpcke Maryellen MacDonald • Julia Evans Natasha Tokowicz Ovid Tzeng• Ping Li Igor Farkas Arturo Hernandez• Yoshinori SasakiRichard Wong Antonella Devescovi• Reinhold Kliegl Jeff Sokolov Beverly Wulfeck• Vera Kempe Janet McDonald Hasan Taman• Elena Pizzuto Stan Smith Dan Slobin• Roman Taraban Patricia Brooks Zhou Jing• Yuki Yoshimura Melita Kovacevic Joe Stemberger• Chris Jones Jared Leinbach Christophe Parisse• Yvan Rose Kees De Bot Phil Pavlik• Nora Presson Yanping Dong Anat Prior• Yanhui Zhang Sue-mei Wu

• NIMH (25 years) NSF (10 years) MacArthur (3 years)

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Economic Assumptions

• Competence in English is crucial for success in the global economy.

• But most of the population of the world does not speak English as L1. So English is L2. Other L2s have parallel roles.

• It is not enough to restrict L2 competence to the elite, since work is becoming increasingly based on language skills.

• Different social and economic configurations will require differing levels of L2 competence.

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Position 1: Early Immersion

• There is a Critical Period for language learning.

• There is a learning/acquisition dichotomy. Late bilinguals can never achieve full L2 competence.

• Therefore, we must start immersion L2 programs at the pre-primary level.

• And spend billions of dollars in exposure, but not really teaching.

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Position 2: Focus on community

• There is a Critical Period and a learning/acquisition dichotomy.

• However, immersion will not work and can conflict with other goals in early childhood education.

• Pre-college education should be in the native language.

• Full bilingualism is only possible if the community becomes bilingual.

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Position 3: Focus on quality

• There is no critical period for second language learning, although there are important age effects.

• Critical period effects are due to entrenchment and competition.

• What is important is not the timing of learning, but the quality of exposure.

• We may still need billions of dollars, but in teaching, not just exposure.

• Languages can be learnt and taught. There is no real learning/acquisition dichotomy.

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The Positions

• Position 1 -- UG: Chomsky, Lenneberg, Krashen, Long, Hurford, Pinker, Newport, Meisel

• Position 2 -- Sociolinguistics: Fishman, Swain, Ervin-Tripp, Gumperz

• Position 3 -- Emergentism: Bates, Ellis, Bialystok, Snow, MacWhinney, Ringbom

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7 Pillars of UG

1.Critical Period -- today’s focus

2.Grammar Gene

3.Speech is Special

4.Modularity

5.Poverty of the Stimulus

6.Sudden Evolution of Language

7.Centrality of Recursion

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7 pillars of emergentism

1. L1-L2 competition and entrenchment2. Gradual evolution3. Modules are made not born4. Polygenic emergent genome5. Speech relies on mammalian abilities6. Learning on input 7. Emergence of recursion

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Which will stand?

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Entrenchment vs. Critical Periods

• Critical Periods are linked to infancy.• Observed drop is not precipitous.• Lateralization is not linked to CP.• Language is not a unitary ability.• Golf, ballet are also age-related.• No mechanism has been discovered.• UG-related syntactic patterns are not strongly

fossilized - Birdsong

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Critical Periods

• Bee dance, cricket song

• Does the ability need a trigger?

• When does it start and end?

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L1 CP≠ L2 CP

L’enfant Sauvage byFrançois Truffaut

Truffaut as Dr. Jean Itard

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How many CPs?

• 6 mos -- deaf children

• 2 -- Early bilingual impacts

• 5 -- Output phonology Flege

• 8 -- Korean adoptees, literacy, orthography

• 13 -- Hemispherectomies, synaptic pruning

• 15 -- Shift in learning, growth of strategies

• 20 -- Beginning of decline

• 40 -- Social difficulties

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Where is the critical drop?

• Newport & Johnson Hakuta actual

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A real CP - Hubel & Weisel

P E R C E N T L E F T V I S U A L C O R T E X C E L L S

R E S P O N D I N G T O C L O S E D R I G H T E Y E

( N o r m a l > 5 0 % )

A g e a t e y e c l o s u r e ( d a y s )

D u r a t i o n 1 0 2 3 3 0 6 0 1 2 0 1 8 0 A d u l t

( d a y s )

0 8 4

3 3 2

6 0

9 0

2 1 2 6

2 7 1 4

3 0 1 9

3 1 1 2

6 5 1 0

9 0 5 9

1 2 0 1 5 5 3

4 8 0 7 0

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What we know

• Critical periods are basic to embryology.

• Critical periods for binocular vision in cats; periods for exposure to song in birds; precocial bird attachment;

• Animals have many instincts; but is language an instinct?

• Kuhl and Werker: brain locks in on early sounds

• Bosch, Juszyck: Auditory system builds early contrasts

• Rosenzweig rats in rich environments get bigger brains.

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A bridge too far

• No evidence for early brain effects

• Mozart for babies

• Linda Acredolo and Baby Signs

• Mobiles, language while you sleep

• Suzuki method

• There is nothing wrong with early L2 learning, but no evidence that it is indispensable

• Early bilingualism ≠ Early L2 learning

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CP for holding pens?

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Chopsticks?

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Multiple language abilities

• Bulgarian grad student who wrote at the top of the class, but had a noticeable accent.

• Hungarian diplomat with perfect English, but nothing to say.

• Japanese grad student with perfect interaction and comprehension, but impossible definite articles and slow test-taking.

• Fossilization for specific German nouns vs. fossilization for some past tenses.

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How can we decide?

• Neurological evidence for a Critical Period• Immigrant studies

Proof of success in native acquisition for age of arrival well past the Critical Period.

Proof of failure after some early age of arrival.

• L2 Classroom studies Big correlational analyses (questionable method) Randomized clinical trials (if we could get funding) Microgenetic method studies (my current preference)

experiments -- can we teach r/l? online methods TalkBank video methods

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Mechanisms of UG

• Genes

• Modules

• Principles, Parameters, Rules

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Mechanisms of Emergence

• Entrainment, physical and social• Adaptation, selection• Competition, strength, reinforcement• Maps, topology, short connections• Self-organized criticality• Resonance• Homeostasis, homeorhesis, feedback

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Why the shift to emergentism?

• Without advanced methods, emergentist cognitive science was not possible

• We didn’t have CHILDES, TalkBank

• Audio, video analysis was primitive

• We couldn’t simulate - PDP, SOM, ART

• We couldn’t image the brain - ERP, fMRI

• We couldn’t study learning in vivo - PSLC.

• With these advances, emergentism is becoming the default stance.

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Unified Competition Model

competition

mapschunking

buffers

codes

resonance

mental models

transfer

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L1 and L2

• The learning goals are the same.

• The available mental processes are the same.

• However, the specific challenges are different.

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L1 Learning Challenges

• Segmenting out words

• Organizing phonological gestures

• Bootstrapping syntax

• Conversational sequencing

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L2 Challenges

• Maximizing positive transfer

• Avoiding negative transfer

• Overcoming age effects Using resonance to overcome entrenchment Proceduralizing declarative structures -

Ullman/Paradis

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Component Theories

1. Competition interactive activation, Bayes

2. Maps SOM, entrenchment

3. Transfer A relation between maps

4. Chunking chunking theory, fluency

5. Buffers processing load, CAPS

6. Resonance memory theory, Pimsleur, coding

7. Mental model perspective, embodiment

8. Codes sociolinguistics, identification

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1. Cue Competition

• Whodunit? The tiger pushes the bear. The bear the tiger pushes. Pushes the tiger the bear. The dogs the eraser push. The dogs the eraser pushes. The cat push the dogs. Il gatto spingono i cani.

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Cues vary across languages

• English: The pig loves the farmer SV > VO > Agreement

• German: Das Schwein liebt den Bauer. Den Bauer liebt das Schwein

Case > Agreement > Animacy>Word Order• Spanish: El cerdo quiere al campesino.

Al campesino le quiere el cerdo. "Case" > Agreement > Clitic > Animacy > Word Order

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Cues

Device ExampleWord Order the dog chases the cat

Function words der - die - das

Affixes was tak-en

Clitics nous, le, ba

Constructions the more -- the merrier

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Central Claim

•Cue validity predicts cue strength

•(Bayesian statistics)[p(function)|form] - comprehension[p(form)|function] - production

Cue validity measured in corporaCue strength measured in experiments

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Cues Compete

“Tigers”-as-Agent “Bear”-as-Agentcompetes

The bear the tigers chases.

preverbal position SV agreement Initial Position

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L1/L2 Competition

Adv + V V + Adv

I often go ... / Je vais souvent ...

competes

Heavy Adv

speaking English:

speaking French:

ADV 1st ADV 2nd

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Strength measured in experiments

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English Children

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Hungarian Children

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Italian Children

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English L1, Dutch L2

Dissertations by Janet McDonald and Kerry Kilborn

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Dutch L1, English L2

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Findings - 22 studies

• Validity predicts Strength.

• Children and L2 learners pick up frequent cues first, then they settle on reliable cues.

• For timed tasks, strong fast cues dominate.

• L2 learners attempt transfer, but then learn cues, as in L1. They gradually reach L1 levels of cue strength.

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2. Maps

• Maps are central to the processing theory. They control transfer, entrenchment, and embodied encoding.

• Maps are emergent:

- Neural systems: Jacobs & Jordan 1992

- Children: Karmiloff-Smith 1997

- Robots: Nolfi 1996, Tani 2002

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Self-organizing lexical maps

Li, Farkas, MacWhinney - Neural network - computer simulation - L1 lexical learning - CHILDES input - no initial organization - short connections

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Gradual Emergence

50, 150, 250, 500 words

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Refining competition

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Bilingual self-organization

ENGLISH SEMANTICS

CHCHINESE SEMANTICS

CHINESE PHONOLOGY

ENGLISH PHONOLOGY

ASSOCIATIVE CONNECTIONS (Hebbian learning)

Self-organization

Self-organization

Word Form

Phonological

Word MeaningCo-occurrence-based

representation(derived from separate component exposed to bilingual

corpus)

Phonological Map

Semantic Map

ChineseSemantics

Chinese Phonology

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Maps implement entrenchment

• Strong items dominate over weak.

• Late L2 items are parasitic on pre-existing L1 forms and maps

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Module Entrenchment

Simultaneous Bilingualism

LX LY

balanced

dominatesL1 L2

Successive Bilingualism

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3. Transfer

• Mapability Item-based (want X) patterns will not transfer Grammatical semantics can be a difficult map Phonology, semantics, pragmatics all map and transfer

• Markedness Unmarked pattern-based will: Adv + V Marked pattern-based is weak: Adv + V + S Semantic/phonological prototypes transfer

• Filtering Japanese r/l second formant transitions. English learners of tones.

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Examples

• taco -> t’aco• wenn (if) -> when • tell me a story -> say me a story• install a new version -> install new version

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The Culprits

• Entrenchment

• Transfer (crosstalk)

• Learning your own errors

• Strategy blockage

• Social culprits

• Aging

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Social Culprits

• Overcommitment too much email, too many committees

• Declining L2 contact environment

• Avoidance of L2 input

• Allegiance to L1

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Aging

• Loss of Auditory Acuity - age effects

• Loss of Motor Control - Parkinsonism

• Cell death -- both cortical and white matter

• Declining transmission speed

• Declining hippocampal storage

• Trauma

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Fighting back

1. Undoing transfer

2. Unblocking social barriers

3. Unblocking strategy barriers

4. Increasing differentiation and resonance

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Overcoming Parasitism

C

L2L1

turtle tortuga

C

L2L1

turtle tortuga

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ERP evidence of transfer - P600

• The cat likes to eat. vs The cat likes to eating.

Plausible (eat)Implausible (eating)P

z

P600

Osterhout & Nicol (1999)

5μV

200 400 600 800

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Su abuela cocina/*cocinando muy bien.Her aunt cooks/*cooking very well.

L1 supports L2

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L1 (English) blocks attention

El/los libros son muy interestantes.The/the books are very interesting.

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L2 cares, L1 oblivious

Ellos fueron a una/*un fiesta.They went to a/a party.

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Behavioral Data

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4. Chunking

•Task: Repeat 坐公共汽車去

•Learn: gōnggòngqìchē “bus” 公共汽車Syllables plus tone encodings fill working memoryChunk: gōnggòng is linked to “public” Chunk: qìchē is linked to “motor car”

Supportive links to charactersCompound is a weak chunk, weak tone sequenceEmbed weak chunk in “sit ___ go” frame 坐 ( 公共汽車 ) 去

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Translation Disfluency

• Do you want to take a bus to Nanjing next week?

• Nǐ xiǎng xià ge xīngqī zuò gōnggòngqìchē qù Nánjīng ma?

• Chinese requires temporal before verb.

• About to say: Nǐ xiǎng zuò

• Pause ….• Insert “xià ge xīngqī”• Continue• Result: Non-fluency

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Chunks mesh into slots

• sit + (vehicle slot) + go

• (adverb slot) + V

• (topic slot) + comment

• Fluent plan emerges from coordination of individual item-based patterns

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PSLC studies of Fluency

• Online Dictation -- French, Chinese

• Yuki Yoshimura’s CMU dissertation on Fluency in Japanese L2 - sentence repetition after reading and listening.

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Repetition and WM

C o m p a r i s o n b e t w e e n r e a d - a l o u d a n d p r o d u c t i o n t i m e

C o m p l e x i t y = s i m p l e

0

2

4

6

8

1 0

1 2

1 4

1 6

4 6 8 1 0

r e a d - a l o u d

p r o d u c t i o n

Length of utterance (sec)

S e n t e n c e L e n g t h

C o m p a r i s o n b e t w e e n r e a d - a l o u d a n d p r o d u c t i o n t i m e

C o m p l e x i t y = c o m p l e x

0

2

4

6

8

1 0

1 2

1 4

1 6

4 6 8 1 0

r e a d - a l o u d

p r o d u c t i o n

Length of utterance (sec)

S e n t e n c e L e n g t h

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Omissions

E r r o r A n a l y s i s b y t y p e

c o m p l e x i t y = c o m p l e x

S e n t e n c e L e n g t h

Number of errors in production

0

0 .2

0 .4

0 .6

0 .8

1

4 6 8 1 0

o m i s s i o n

r e t r a c e

g r a m m a t i c a l

e r r o r

s u b s t i t u t i o n

a d d i t i o n

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Adding Novel Words

E f f e c t o f n o v e l w o r d s

L i s t e n i n g g r o u p x R e a d i n g g r o u p

6 0 0 0

8 0 0 0

1 0 0 0 0

1 2 0 0 0

1 4 0 0 0

1 6 0 0 0

z e r o 1 2

L i s t e n i n g

R e a d i n g

Length of utterance (ms)

N u m b e r o f n o v e l w o r d s i n e a c h s e n t e n c e

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Friederici

• German Natives show for semantic violations: N400 for syntactic violations: ELAN & P600

• L2 Russian natives - 5 years in Germany for semantic violations: N400 for syntactic violations: no ELAN, but P600

• Brocanto and mini-Nihongo Learners: ELAN and P600

• fMRI Conclusion: L1 and L2 use same areas, but L2 relies more on Broca’s

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5. Buffers

• Competition occurs in buffers

• Incrementalism, role-slot filling

• This is developed in MacWhinney (1987) Kempen & Hoenkamp (1987) Levelt (1990) O’Grady (2006)

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6. Resonance

• Graduated interval recall• Multimodal consolidation • Self-organized criticality

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Graduated interval recall

•Pimsleur 67

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Neural Basis

Wittenburg et al. 2002

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Consolidation Circuits

Sound Meaning

Basal Ganglia

Hippo

campus

Dynamic

Scaffold

Consolidation

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Chinese Resonance

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Consolidation and Time

• Bones, muscles, cell walls, mitochondria, and immune system becomes stronger after periods of use and breakage.

• These systems respond to pressures across time frames. (slow muscles, fast muscles)

• Neurons work the same way.

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Math Models: Pavlik 2006

t=time from practiced=decay raten=number of presentationsm=memory activationa=base decay ratec=scales effect of activation on decayu=maximal study benefitv=rise to asymptote speed

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Four Pools

• Pool 1 – item is strong, then wait• Pool 2 – item is weak enough to make practice efficient but

strong enough to make drilling more efficient• Pool 3 – item is weak and retrieval will fail, so study

practice is more efficient• Pool 4 – unpracticed items• Algorithm selects items in this order: 2, 3, 4, 1• Learned items are removed from pools

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Optimization really helps

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7. Mental models

• We build up mental models through perspective-taking.

• Comprehensible input -- L2 speaker can construct a coherent mental model.

• L2 conversation-based teaching has to make sure the mental model is on track.

• Frames, scaffolds, can support this.

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8. Codes

• Code-switching

• L2 is a code choice

• Codes involve perspective taking in mental models

• Role of video in learning, identification

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The Unified Model

• Competition is central. • Both L1 and L2 are emergent.• Item-based constructions compete in L1 and L2

learning.• Transfer arises from entrenchment in maps.• Fluency develops through chunk meshing.• Resonance and spacing produce robust learning.• Conversation supports perspective switching and

model construction.

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Conclusions

• The Unified Model integrates our understanding of first and second language acquisition.

• Language learning relies on emergentist processes.

• Language can be taught and learned.• Age-related effects arise from entrenchment

and social commitment, not UG.

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Links

• http://psyling.psy.cmu.edu/papers

• http://psyling.psy.cmu.edu/talks

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Aphasics - Word Order

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Aphasics - Agreement