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EmergentismE 1

The Emergence of Language (from Brain, Body, and Discourse)The Emergence of Language (from Brain, Body, and Discourse)

Brian MacWhinney- CMU

Emergentism2

The Special Gift Paradigm

1. Grammar Gene2. Speech is Special3. Modularity4. Critical Period*5. Poverty of the Stimulus*6. Sudden Evolution of Language*7. Centrality of Recursion*

Emergentism3

Genetic Locus?

Emergentism4

Cortical Module?

Emergentism5

Hard-wired modules?Hard-wired modules?Hard-wired modules?Hard-wired modules?

Emergentism6

Speech is Special?

Emergentism7

Sudden evolution?

• 7 MYA bipedalism• 4 MYA tools, opposing thumb• 3 MYA parietal expansion, TOM• 1.5 MYA general cortical expansion

• .3 MYA expanding pulmonic support• .1 MYA glottal control• 30,000 creativity explosion

Emergentism8

Expiration of the Special Gift

• Wild children are neurologically impaired

• Newport and Johnson show no point of sudden loss

• Recovery of language at 13 after hemispherectomy -- Vargha-Khadem

• L2 age effects not unique to language learning-- ballet, golf, even math

• Entrenchment account of L2

Emergentism9

Logical Problem?

• Mothers speak grammatically - Newport

• Degree-0 learnability - Lightfoot

• Competition provides the negative evidence - MacWhinney

• Error-free learning doesn’t occur - Pullum

• The Stimulus isn’t impoverished after all

Emergentism10

Stipulation and the Gift

• Rules have been the backbone of descriptive linguistics

• Rules can be stipulated• Children learn rules - Brown, Marcus, Pinker

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Big Mean Rules

Emergentism12

Big Mean Flowcharts

Emergentism13

Changing theories …

• Rules are softening• Evolution is stretching out• Modularity is getting plastic• Genome is becoming exaptive

Emergentism14

Kinder, gentler rules

• Pinker (1984) add -ed

• Aslin, Newport, Saffran (1999) golabu, pitaku

• Marcus’s (2000) baby rules S -> A + B +A

ga-ti-gaga-ti-gaga-na-gaga-na-gaga-gi-gaga-gi-gaga-la-gaga-la-gali-na-lili-na-lili-ti-lili-ti-lili-gi-lili-gi-lili-la-lili-la-lini-gi-nini-gi-nini-ti-nini-ti-nini-na-nini-na-nini-la-nini-la-nita-la-tata-la-tata-ti-tata-ti-tata-na-tata-na-tata-gi-tata-gi-ta

Emergentism15

But …

Core: X-bar, Merge,

recursion

Periphery

Lexicon, dialect, collocation, pragmatics, function, ….

Emergentism16

Emergentism

• Not: empiricism vs. nativism

• Instead: emergentism vs. stipulationism

Emergentism17

Emergence vs stipulationEmergence vs stipulation

Emergentism18

Emergent structure in Honeycombs

Emergentism19

Emergent Columns

Emergence of Oriented On-Off Neurons

Emergentism20

Emergent Computation

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Physical emergenceClosures inhibit voicing

Many languages lack /b/, few lack /p/

time 0 time 1 time 2

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Entrainment - Huygens

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Jaw entrains the glottis

Lip-smacking rhythms (Macneilage & Davis, 2001)

Thelen & Iverson, 1998 - jaw entrains glottis

Hippocampal timers (Buzsáki 2004)

Conversational synchrony (Wilson & Wilson 2005)

Emergentism24

Babbling entrains gesture

• Iverson, Thelen• Central role of rhythm• Babbling and gesture both arise from Broca’s area

• McNeill’s theory of growing points with gesture at the root of thought

Emergentism25

Dissipative Systems

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Catalysis

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Deformation

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Emergentist theory asks:

• How did a structure emerge?• Under what time-frame did it emerge?

• What dynamic processes are involved?

• How stable is the structure?• How does removal of supports alter the emergence?

Emergentism29

• Entrainment, physical and social• Adaptation, selection• Competition, strength• Hebbian learning, reinforcement• Topology, short connections• Self-organized criticality, catalysis

• Resonance• Deformation, induction, regulation

Mechanisms of Emergence

Emergentism30

Why now?

Without advanced methods, emergentist cognitive science was not possible

• We didn’t have CHILDES, TalkBank• Audio, video analysis was primitive - TalkBank

• 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.

Emergentism31

Sources of emergence

• Brain: Neural networks, short connections, area histology, spike propagation

• Body: Embodied cognition, the vocal apparatus

• Society: Discourse, roles, theory of mind

Emergentism32

Time-frames of EmergenceTime-frames of Emergence

1. Archaeogenetic2. Phylogenetic3. Embryological4. Developmental5. Online6. Diachronic

Emergentism33

The Emergence of Language

Lawrence Erlbaum Associates, 1999

Elman, J. et al (1996)

Rethinking Innateness

MIT Press

Books

Emergentism34

Examples

1. Morphological paradigms2. From lexicon to syntax3. Mutual exclusivity4. Perspective flow

Emergentism35

1. Neural Networks for Morphology

units

weights

learning rule

activations

connections

Emergentism36

Summing activation

x1 x2 x3

y1

z1 z2 z3

y2

.54

.22

Emergentism37

Neurons don’t send Morse code

Emergentism38

Memory molecules?

Worm Runners Digest

Training, grinding, feeding planaria

Emergentism39

The architecture

INPUT UNITS

OUTPUT UNITS

168 Left-justified 143 phonological 5 semantic

200 hidden20 gendernumber units

200 hidden7 units

der die das des dem den

17 case cues 11 phono

10 case units

•  •  •  •   •  •

Emergentism40

Networks work

• It worked -- it learned the input

• It generalized as in German and English

• It matched the developmental data

Emergentism41

With Limitations

The homophony problemringed -- rang -- wrung

The masquerading morpheme problem-chen-en in Nacken, Hafen vs -en in Wissen

The “underwent” problemMutter should guarantee die Grossmutter

The zero derivation problem

schlagen should predict der Schlag

The early “went” problem

Emergentism42

2. The answer

• Morphological learning must emerge from a lexical base

• Therefore, we first have to simulate the learning of the lexicon

Self-organizing lexical maps

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

Gradual Emergence

50, 150, 250, 500 words

DevLex Model

Bilingual self-organization

ENGLISH SEMANTICS

CHCHINESE SEMANTICS

CHINESE PHONOLOGY

ENGLISH PHONOLOGY

ASSOCIATIVE CONNECTIONS (Hebbian learning)

Self-organization

Self-organization

Word Form

Phonological

Word Meaning

Co-occurrence-based representation(derived from separate component exposed to

bilingual corpus)

Phonological Map

Semantic Map

ChineseSemantics

Chinese Phonology

Refining competition

Maps implement entrenchment

• Strong items dominate over weak.

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

Module Entrenchment

Simultaneous Bilingualism

LX LYbalanced

dominatesL1 L2

Successive Bilingualism

Parasitism and Transfer

C

L2L1

turtle tortuga

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

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

5. Emergence from Resonance

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

Graduated interval recall

Pimsleur 67

Neural Basis

Wittenburg et al. 2002

Optimization really helps

Chinese Resonance

Consolidation Circuits

Sound Meaning

Basal Ganglia

Hippo

campus

Dynamic

Scaffold

Consolidation

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.

• They are sensitive to: one-trial learning (amygdalal input) local episodic learning (hippocampal input) embodied learning (self-motion) statistical learning (basal ganglia, circuits) strategic resonant learning (frontal input)

Emergentism60

Example 4: Perspective and grammar

• Animal cognition is modular (bees)

• Perspective integrates across modules

• Language expresses perspective and changes in perspective

EmergentismE 61

Perspective

direct experience

deixis rolesplans

perspective perspectiveperspective perspective

language as a functional neural circuit

unified image

Emergentism62

The dorsal and the ventral paths

The dorsal and the ventral paths

enactive

depictive

Emergentism63

Mirror neurons -- Rizzolatti

Mirror neurons -- Rizzolatti

E grabs M grabs E with pliers M grabs

Emergentism64

Monkey grabbing in the dark

Monkey grabbing in the dark

Emergentism65

Perspective shift(MacWhinney y Pléh (1987)Perspective shift(MacWhinney y Pléh (1987)

# cambioSS: The dog that chased the cat bit the horse.

0

OS: The dog chased the cat that bit the horse. 1-

OO: The dog chased the cat the horse bit. 1+

SO: The dog the cat chased bit the horse. 2

SS > OS = OO > SOThe dog the cat the boy liked chased snarled. 4+

(dog -> cat -> boy -> cat -> dog)

Emergentism66

Ambiguity and perspective flow

• John saw the Grand Canyon flying to New York.• The women discussed the dogs on the beach. • Although John always runs, a mile seems like a

long distance to him.

• I ordered her pancakes.• Visiting relatives can be a nuisance.• The horse raced past the barn fell.

Emergentism67

Constructions that mark perspective shift

Passive AdverbalizationDouble Object BindingInverseDislocation

Obviative CleftingFictive agentTopicalización

Conflation PossessiveComparative EllipsisComplementation Coordination ….

Emergentism68

Other sample topics: the emergence of X from Y

• CV syllable from lip-smacking• Final devoicing from syllable structure

• Ergativity from subject omission

• Locatives from body parts• Superordinates from most frequent subordinates

• Use of Broca’s for ASL

Emergentism69

Getting it wrong

QuickTime™ and aMotion JPEG A decompressor

are needed to see this picture.

Emergentism70

Falsifiability of Emergentism?

• Core claim : all processes arise from dynamic interactions

• Core claim: Language arises from external pressures

• Conceptualization cannot be falsified, but specific implementations can.

• Specific implementations must be described mechanistically. This is really difficult.

Emergentism71

Summary

• Emergentism vs. Stipulationism• Emergence on five time-frames• Emergence from Brain, Body, and Society

• Four examples: morphology, syntax, ME, perspective

• Emergentist accounts can be wrong.• But emergentism cannot be falsified, it can only be implemented. This is really difficult.

Emergentism72

Elman, J. (1990). Finding structure in time. Cognitive Science, 14, 179-212.Elman, J. L. (1999). The emergence of language: A conspiracy theory. In B. MacWhinney (Ed.), The emergence of language (pp. 1-28). Mahwah, NJ: Lawrence Erlbaum Associates.Farkas, I., & Li, P. (2001). Modeling the development of lexicon with a growing self-organizing map. NIPS.Li, P., & MacWhinney, B. (1996). Cryptotype, overgeneralization, and competition: A connectionist model of the learning of English reversive prefixes. Connection Science, 8, 3-30.MacWhinney, B. (1977). Starting points. Language, 53, 152-168.MacWhinney, B. (1978). The acquisition of morphophonology. Monographs of the Society for Research in Child Development, 43, Whole no. 1, pp. 1-123.MacWhinney, B. (1993a). Connections and symbols: Closing the gap. Cognition, 49, 291-296.MacWhinney, B. (1993b). Is there a logical problem of language acquisition? In C. Smith (Ed.), Early Cognition and the Transition to Language. Austin, TX: University of Texas Press.MacWhinney, B. (1999). The emergence of language from embodiment. In B. MacWhinney (Ed.), The emergence of language (pp. 213-256). Mahwah, NJ: Lawrence Erlbaum.MacWhinney, B. (2000). Lexicalist connectionism. In P. Broeder & J. Murre (Eds.), Models of language acquisition: Inductive and deductive approaches (pp. 9-32). Cambridge, MA: MIT Press.MacWhinney, B., & Leinbach, J. (1991). Implementations are not conceptualizations: Revising the verb learning model. Cognition, 29, 121-157.MacWhinney, B. J., Leinbach, J., Taraban, R., & McDonald, J. L. (1989). Language learning: Cues or rules? Journal of Memory and Language, 28, 255-277.Miikkulainen, R. (1993). Subsymbolic natural language processing. Cambridge, MA: MIT Press.Miikkulainen, R., & Mayberry, M. R. (1999). Disambiguation and grammar as emergent soft constraints. In B. MacWhinney (Ed.), The emergence of language (pp. 153-176). Mahwah, NJ: Lawrence Erlbaum Associates.Rumelhart, D. E., & McClelland, J. L. (1986). On learning the past tense of English verbs. In J. L. McClelland & D. E. Rumelhart (Eds.), Parallel distributed processing: Explorations in the microstructure of cognition (pp. 216-271). Cambridge: MIT Press.

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