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

The Emergence of Language ( from Brain, Body, and Discourse ). Brian MacWhinney- CMU. The Special Gift Paradigm. Grammar Gene Speech is Special Modularity Critical Period* Poverty of the Stimulus* Sudden Evolution of Language* Centrality of Recursion*. Genetic Locus?. Cortical Module?.

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

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  1. The Emergence of Language (from Brain, Body, and Discourse) Brian MacWhinney- CMU EmergentismE

  2. The Special Gift Paradigm • Grammar Gene • Speech is Special • Modularity • Critical Period* • Poverty of the Stimulus* • Sudden Evolution of Language* • Centrality of Recursion* Emergentism

  3. Genetic Locus? Emergentism

  4. Cortical Module? Emergentism

  5. Hard-wired modules? Emergentism

  6. Speech is Special? Emergentism

  7. 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 Emergentism

  8. 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 Emergentism

  9. 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 Emergentism

  10. Stipulation and the Gift • Rules have been the backbone of descriptive linguistics • Rules can be stipulated • Children learn rules - Brown, Marcus, Pinker Emergentism

  11. Big Mean Rules Emergentism

  12. Big Mean Flowcharts Emergentism

  13. Changing theories … • Rules are softening • Evolution is stretching out • Modularity is getting plastic • Genome is becoming exaptive Emergentism

  14. Kinder, gentler rules ga-ti-ga ga-na-ga ga-gi-ga ga-la-ga li-na-li li-ti-li li-gi-li li-la-li ni-gi-ni ni-ti-ni ni-na-ni ni-la-ni ta-la-ta ta-ti-ta ta-na-ta ta-gi-ta • Pinker (1984) • add -ed • Aslin, Newport, Saffran (1999) • golabu, pitaku • Marcus’s (2000) baby rules • S -> A + B +A Emergentism

  15. Core: X-bar, Merge, recursion But … Lexicon, dialect, collocation, pragmatics, function, …. Periphery Emergentism

  16. Emergentism • Not: • empiricism vs. nativism • Instead: • emergentism vs. stipulationism Emergentism

  17. Emergence vs stipulation Emergentism

  18. Emergent structure in Honeycombs Emergentism

  19. Emergent Columns Emergence of Oriented On-Off Neurons Emergentism

  20. Emergent Computation Emergentism

  21. Physical emergenceClosures inhibit voicing Many languages lack /b/, few lack /p/ time 2 time 1 time 0 Emergentism

  22. Entrainment - Huygens Emergentism

  23. 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) Emergentism

  24. 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 Emergentism

  25. Dissipative Systems Emergentism

  26. Catalysis Emergentism

  27. Deformation Emergentism

  28. 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? Emergentism

  29. Mechanisms of Emergence • Entrainment, physical and social • Adaptation, selection • Competition, strength • Hebbian learning, reinforcement • Topology, short connections • Self-organized criticality, catalysis • Resonance • Deformation, induction, regulation Emergentism

  30. 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. Emergentism

  31. Sources of emergence • Brain: Neural networks, short connections, area histology, spike propagation • Body: Embodied cognition, the vocal apparatus • Society: Discourse, roles, theory of mind Emergentism

  32. Time-frames of Emergence • Archaeogenetic • Phylogenetic • Embryological • Developmental • Online • Diachronic Emergentism

  33. Books The Emergence of Language Lawrence Erlbaum Associates, 1999 Elman, J. et al (1996) Rethinking Innateness MIT Press Emergentism

  34. Examples 1. Morphological paradigms 2. From lexicon to syntax 3. Mutual exclusivity 4. Perspective flow Emergentism

  35. 1. Neural Networks for Morphology Emergentism

  36. Summing activation Emergentism

  37. Neurons don’t send Morse code Emergentism

  38. Memory molecules? Worm Runners Digest Training, grinding, feeding planaria Emergentism

  39. The architecture Emergentism

  40. Networks work • It worked -- it learned the input • It generalized as in German and English • It matched the developmental data Emergentism

  41. With Limitations The homophony problem ringed -- rang -- wrung The masquerading morpheme problem -chen -en in Nacken, Hafen vs -en in Wissen The “underwent” problem Mutter should guarantee die Grossmutter The zero derivation problem schlagen should predict der Schlag The early “went” problem Emergentism

  42. 2. The answer • Morphological learning must emerge from a lexical base • Therefore, we first have to simulate the learning of the lexicon Emergentism

  43. Self-organizing lexical maps Li, Farkas, MacWhinney - Neural network - computer simulation - L1 lexical learning - CHILDES input - no initial organization - short connections

  44. Gradual Emergence 50, 150, 250, 500 words

  45. DevLex Model

  46. Word Form Phonological Phonological Map ENGLISH PHONOLOGY Self-organization CHINESE PHONOLOGY ASSOCIATIVE CONNECTIONS (Hebbian learning) Word Meaning Co-occurrence-based representation (derived from separate component exposed to bilingual corpus) Self-organization CHCHINESE SEMANTICS ENGLISH SEMANTICS Semantic Map Bilingual self-organization Chinese Phonology Chinese Semantics

  47. Refining competition

  48. Maps implement entrenchment • Strong items dominate over weak. • Late L2 items are parasitic on pre-existing L1 forms and maps

  49. Module Entrenchment Simultaneous Bilingualism LX LY balanced Successive Bilingualism L1 L2 dominates

  50. C L1 L2 Parasitism and Transfer turtle tortuga

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