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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*
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Genetic Locus?
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Cortical Module?
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Hard-wired modules?Hard-wired modules?Hard-wired modules?Hard-wired modules?
Emergentism6
Speech is Special?
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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
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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
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Big Mean Flowcharts
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Changing theories …
• Rules are softening• Evolution is stretching out• Modularity is getting plastic• Genome is becoming exaptive
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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
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But …
Core: X-bar, Merge,
recursion
Periphery
Lexicon, dialect, collocation, pragmatics, function, ….
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Emergentism
• Not: empiricism vs. nativism
• Instead: emergentism vs. stipulationism
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Emergence vs stipulationEmergence vs stipulation
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Emergent structure in Honeycombs
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Emergent Columns
Emergence of Oriented On-Off Neurons
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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)
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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
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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
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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.
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Sources of emergence
• Brain: Neural networks, short connections, area histology, spike propagation
• Body: Embodied cognition, the vocal apparatus
• Society: Discourse, roles, theory of mind
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Time-frames of EmergenceTime-frames of Emergence
1. Archaeogenetic2. Phylogenetic3. Embryological4. Developmental5. Online6. Diachronic
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The Emergence of Language
Lawrence Erlbaum Associates, 1999
Elman, J. et al (1996)
Rethinking Innateness
MIT Press
Books
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Examples
1. Morphological paradigms2. From lexicon to syntax3. Mutual exclusivity4. Perspective flow
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1. Neural Networks for Morphology
units
weights
learning rule
activations
connections
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Summing activation
x1 x2 x3
y1
z1 z2 z3
y2
.54
.22
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Neurons don’t send Morse code
Emergentism38
Memory molecules?
Worm Runners Digest
Training, grinding, feeding planaria
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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
• • • • • •
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Networks work
• It worked -- it learned the input
• It generalized as in German and English
• It matched the developmental data
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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
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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)
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Example 4: Perspective and grammar
• Animal cognition is modular (bees)
• Perspective integrates across modules
• Language expresses perspective and changes in perspective
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Perspective
direct experience
deixis rolesplans
perspective perspectiveperspective perspective
language as a functional neural circuit
unified image
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The dorsal and the ventral paths
The dorsal and the ventral paths
enactive
depictive
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Mirror neurons -- Rizzolatti
Mirror neurons -- Rizzolatti
E grabs M grabs E with pliers M grabs
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Monkey grabbing in the dark
Monkey grabbing in the dark
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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.
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Constructions that mark perspective shift
Passive AdverbalizationDouble Object BindingInverseDislocation
Obviative CleftingFictive agentTopicalización
Conflation PossessiveComparative EllipsisComplementation Coordination ….
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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.
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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.
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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.
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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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