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Explore the pillars of language evolution theory by Brian MacWhinney through cognitive attainments, skill networks, and social influences. Delve into the critical periods and recursive patterns that shaped human communication.
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The Sudden Evolution of Language? -- Pillar #6 Brian MacWhinney Psychology Carnegie Mellon Collaborative Commentary - MacWhinney
The Seven Pillars of UG • Grammar Gene • Speech is Special • Language Organ and Modularity • Critical Periods • Poverty of the Stimulus • Sudden Evolution of Language • Recursion - LND Collaborative Commentary - MacWhinney
Data Sources • Direct Evidence • Genetics • Fossils, reconstructions, comparative physiology • Settlement patterns, habitat range • Tools, artifacts, art • Climactic changes - glaciation, eruptions • Indirect Evidence • Human ontogeny, language acquisition • Neurology • Linguistics -- function, gesture, phonology, recursion • Evolutionary Psychology • All of the above across other primates and other species Collaborative Commentary - MacWhinney
Core Issues • Saltation vs. Coevolution • Developing an account that is consistent with the observed data • Recent focus by Hauser, Chomsky, Fitch on recursion as the core of language • Can we use this account to predict new findings and results in: • Comparative behavior • Comparative neurology • Fossils, tools, settlement, genetics • Evolutionary Neural Networks • Evolutionary Psychology Collaborative Commentary - MacWhinney
Lessons from Child Language Language learning involves linking a series of abilities • Audition • Segmentation • Imitation • Articulation, Timing • Attention • Lexicon • Combination • Recursion • …. Collaborative Commentary - MacWhinney
Lessons from Functional PsychoLinguistics • Language is grounded on cognition in • Direct perception • Space/Time/Aspect deixis • Causal Roles • Social Roles • Each level is organized by perspective • Incremental processing starts from embodied core -- McNeill • Compilation relies on item-based patterns and recursion Collaborative Commentary - MacWhinney
Lessons from Evolutionary Theory • Adaptations must lead to individual reproductive advantage • Group advantages are secondary • Advantages can be linked to disadvantages (sickle cell, autism) • Populations are dynamic • Changes are gradual and emergent - but this is still debated Collaborative Commentary - MacWhinney
Skill Network • Each attainment builds on previous ones. • Each relies on abilities that are found in a more limited form in our primate cousins. • Each ability can in turn be decomposed into subcomponents. • Given this, simple saltation is impossible. • However, some key changes could foster productive co-evolution of the network. • What forces could support continued progress? Collaborative Commentary - MacWhinney
Continued Support • The shift to bipedalism continued across three million years. • The role of the freed hands changed over time, but was a continuing drive. • Social forces exerted continual pressure. • Social forces combined with the role of the hands. Collaborative Commentary - MacWhinney
A Grounded Social Climber • As a bipedal, man is like the kangaroo. • Unlike the kangaroo, hominids were climbers who used their hands. • The hands were then used to control tools, but … • Forced into face to face contact, the hands could also contribute to social interaction. Collaborative Commentary - MacWhinney
Proto-Mimesis • Bipedalism opens up face-to-face contact • The hands operate in the contact area • This produces proto-mimesis (Zlatev) with pointing and teaching • Vocalization locks in attention Collaborative Commentary - MacWhinney
Partial Differences • Some ape lexical learning, but incomplete • Some ape planning abilities (Goodall straws), but incomplete • Some ape intersubjectivity, but incomplete • Some ape pointing, but incomplete Collaborative Commentary - MacWhinney
Sharper Changes • Cortical control of vocalization • Duality of patterning - Recursion? • Brain expansion • Physical changes • Articulation - teeth, mouth • Phonation - vocal cords, bent vocal tract • Thumb • Posture, parturition, neotony Collaborative Commentary - MacWhinney
Problems with Saltationism • Only deals with the last 100,000 years, not the last 6 million years • Ignores 300% increase in brain size • Ignores many morphological changes • Ignores homo erectus expansion. • Fails to deal with gesture • Fails to deal with skill network • Etc… Collaborative Commentary - MacWhinney
Five Periods • Bipedalism 7-4 MYA • Social Cohesion 4-2 MYA • Mimesis 2-.2 MYA • Phonology 300,000 - 50,000 • Creativity 50,000 - now Collaborative Commentary - MacWhinney
Cognitive Attainments • Bipedalism • Basic imagery, tool use, spatial recursion • Social Cohesion • Cortical control of vocal-auditory channel • Mimesis • Gestural item-based pattern, prosody • Phonology • Phonemic system, phonological loop • Creativity • Item-based, perspective Collaborative Commentary - MacWhinney
1. Bipedalism • Coppens East Side Story 10-7 MYA • Jungle -> savannah (lakes?) • Handedness and affordances for arboreal • Deixis for terrestrial • Tool use and locomotion (primary) • Communication (secondary) • Groups needed for protection against predators Collaborative Commentary - MacWhinney
Neuronal Support • Parietal reorganization at 4MYA- Holloway • Body image projection • Navigation and deixis • Spatial images support recursion • Facial recognition (supramarginal) • Tools, navigation, social cohesion Collaborative Commentary - MacWhinney
2. Social Cohesion • Expansion at 4MYA, contraction at 3.5MYA • Habilis/ergaster vs. australopithecus • Competition was won by the most cohesive and planful groups • Good social partners • Sexual arms race • Dominance vs. external aggression • Role of dialect marking • Dunbar, Power, Worden social accounts Collaborative Commentary - MacWhinney
Cortical Control of Vocalization • Primate system links • Arousal (amygdala, brainstem) • Motivation (basal ganglion) • Memory (limbic, hippocampus) • The primate external striatum was absorbed by the neocortex, giving cortical control • Control is now from the supplementary motor and anterior cingulate Collaborative Commentary - MacWhinney
3. Mimesis • Parallel evolution • The gestural channel contained the content • The vocal channel contained the social glue • Disorganized nature of mimetic processes • Inefficient gestalt encoding • Mechanisms: • Imitation • Pointing • Joint attention (Intersubjectivity) • Perspective-taking Collaborative Commentary - MacWhinney
Monkey See, Monkey Do • Whiten 2003 Patteson 1978 Collaborative Commentary - MacWhinney
Early Gestalts • Mimetic patterns do not separate verbs and nouns • Me-hand-grab-axe-up-swing-down-cut-chips-sound • This can be imitated as a Gestalt, but Gestalt storage is expensive • I chop wood. Collaborative Commentary - MacWhinney
Satisfied Preconditions • Hands were free • Hands were controlled by complex plans • Spatial maps had evolved for self and group • The visual system could generate and store images • Visual images encoded hierarchically and open to recursion • Vocalization and eye-gaze controlled attention in face-to-face interaction Collaborative Commentary - MacWhinney
Neuronal Support • Tripling in brain size (some allometric) • Earlier growth was in specific areas • Parietal • Cortical control of vocal channel • New pressures • Need for full simulation of the body for mimesis • Storage of mimetic sequences • Processing of mimetic operators • Teaching of mimetic sequences by mothers • Perspective-switching Collaborative Commentary - MacWhinney
How successful? • Expansion to all of Eurasia • At the expense of other hominids • Big, unorganized brain • No vocal systematization • Climate changes of the Pleistocene led to new pressures Collaborative Commentary - MacWhinney
4. Phonology • Phonological patterning • MacNeilage and vocal gesture • Gupta and MacWhinney and the phonological loop • Making efficient use of lexical storage • Capitalizes on evolution in TOM and perspective Collaborative Commentary - MacWhinney
Vocal Adaptations • Lower larynx and hence larger (and distinct) pharynx • Longer local cords (at least in adult males) • Aerodynamical streamlined conus elasticus (underside of vocal cords • Expanded neuronal control of intercostals at 300,000 These adaptations produce loud, efficient, and low-pitched vocalizations (but not necessarily speech itself). Collaborative Commentary - MacWhinney
Facial Musculature Collaborative Commentary - MacWhinney
Ears, Teeth Collaborative Commentary - MacWhinney
Vocal Cords Collaborative Commentary - MacWhinney
Source-Filter Theory Collaborative Commentary - MacWhinney
Bent Vocal Tract Collaborative Commentary - MacWhinney
Possible Vowels Collaborative Commentary - MacWhinney
Neanderthal and Cro-Magnon Collaborative Commentary - MacWhinney
Neuronal Support • Broca’s for lip-smacking becomes Broca’s for CV syllabic framework • Phonological loop involving superior temporal stores lexical items • Lexical items have access to all of the brain, but not dynamically Collaborative Commentary - MacWhinney
Reuse of earlier mechanisms • Phonological store allows vocal rehearsal • Hippocampus stores the episodic basis of lexical meanings • DLPFC stores plans for tools use and mimesis • Integrated frontal function constructs group relations: kinship, reciprocals, hierarchy Collaborative Commentary - MacWhinney
5. Phoenix • Narrowing of evolutionary window at 70,000 • Computed through females, but males must be similar • Perhaps due to Toba Batak, perhaps to a pandemic • Survivors were an interesting subset of the earlier population • Phoenix from the Ashes Collaborative Commentary - MacWhinney
Creativity Explosion • Artifacts at 50,000 - carved bone, amulets • Cave paintings at 30,000 • Burial at 30,000 • Opposition to Neanderthal • Mithen theory of demodularization Collaborative Commentary - MacWhinney
Suspects • Perspective • Recursion • Priesthood Collaborative Commentary - MacWhinney
Perspective Hypothesis unified embodied image language as a functional neural circuit perspective perspective perspective perspective direct experience space/time deixis plans social Collaborative Commentary - MacWhinney
Evolution and Perspective • The five periods do not match the four cognitive levels • But each level was constructed as a part of this process • Each was progressively refined over time • The phonetic revolution underlies the grammar, but the grammar maps to cognition, not phonology Collaborative Commentary - MacWhinney
But… • TOM is developed in chimps • Perspective was important during mimesis • Imitation was present • Imagery was present • Mirror neurons are in monkeys Collaborative Commentary - MacWhinney
Recursion • Next talk: What Chomsky means by recursion reduces to item-based patterns • Item-based patterns require • Items • Slots • Features • Clustering Collaborative Commentary - MacWhinney
Patterns from Combinations • cookie = “would you please open the cupboard door and bring me down a cookie” • want ##### cookie • want # cookie • want cookie • Nim Chimpsky, Washoe, Sara, Lana Collaborative Commentary - MacWhinney
Item-based Patterns • my + X • Position • Meaning relation • Possible fillers • My little dolly • Where + X • Where the wheel goes? • Where goes the wheel? Collaborative Commentary - MacWhinney
--- breaks __kick __ __ running Throw__ __give__ __ Sockets are action-based Collaborative Commentary - MacWhinney
Feature-based patterns • big + X, nice + X …. • Adj + X • Adj + N • But what about? • Actor + Action • Subject + Verb • Topic + Comment Collaborative Commentary - MacWhinney
Patterns to Creativity • Item-based patterns provided full recursion • Recursion linked dynamically to perspectival systems • Articulate language users became priests • Priests constructed the afterworld and myth Collaborative Commentary - MacWhinney