Language

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Language

• Does the child come factory equipped with any
  knowledge of the world?
• What is the difference between studying natural
  competences and side-effects?
• What does learning mean?
• How many learning processes are there?
• Is instinct the opposite of learning?
• What is the design of the instinct that causes
  learning in a given domain?

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Communication versus Language

• Communication in other animals
• Sound one meaning
• Small vocabulary
• No rules for combination
• Human language
• Sound meaning arbitrary relationship
• Large vocabulary
• Finite set of symbols ? infinite number of ideas

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What is language? A grammar?Definitions

• A language is a rule-governed system that allows
  one to produce an infinite number of sentences
  from a finite set of symbols
• A grammar is a system that arranges or groups
  words together into meaningful phrases and
  sentences

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Language as a rule-governed system

• Hierarchical structure
• Sounds versus phonemes
• Morphemes content versus function
• Phrases
• Sentences

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Phonemes

• Sounds versus phonemes
• Phoneme a sound distinction that is relevant to
  speech perception
• Bus v. Bussss not phoneme diff
• Bus v. fuss v. but phoneme diffs
• 40 phonenes in English
• Sound distinctions formed by different
  arrangements of the vocal tract
• Pa ta (lips, palatte) ba pa (voice onset time)

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Different languages use different sets of phonemes

• Efharisto !Kung clicks
• Every child starts out able to make all phonemes
• Babies start to lose the ability to make phonemes
  not in their language
• Start losing by 12 months By 20s, lose ability
• We can perceive 6 phonemes / second
• 250 words/ minute
• Even though NO gaps or silences that mark off one
  speech unit from another
• Unlike writing. Jeet?

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Morphemes

• Phonemes combine to form morphemes
• Morpheme the smallest language unit that carries
  a bit of meaning
• Strangers 3 morphemes
• Strange, er (one who is), s (more than one)
• Stranger one who is odd or alien strangers
  ones who are odd or alien
• Content morphemes (strange)
• Function morphemes (er, and)
• Serve grammatical functions

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Language as a rule-governed system

• In English 80,000 morphemes
• Combine to form several hundred thousand words
• Words strung together to form phrases
• Phrases strung together to form sentences

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Language as a rule-governed system

• Sentence
• Mini-drama Doer, act, done-to
• Doer Noun phrase
• Act Verb
• Done-to Object

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Same meaning, different grammatical forms

• Propositions (sentences in the language of
  thought)
• Mental representation of meaning
• Same proposition can be expressed by different
  grammatical forms
• Different surface structure to the sentence
• E.g., active, passive

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Language as a rule-governed system

• Grammatical rules or a system of syntax
• Rules for stringing phonemes, morphemes, words
  together to make meaningful phrases and sentences

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Grammar

• Prescriptive grammar (school)
• Dont end sentence with preposition, dont split
  infinitives
• Psychogrammar (psycholinguists sense)
• Refers to mental structures
• A finite rule system or program or circuit design
  capable of generating and recognizing the
  sentences of a language
• Possessed by every native speaker
• Rules usually implicit

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A Grammar Instinct?

• The grammars of all human languages are slight
  variations on a single underlying system
  psychogrammar
• All human societies have language
• Lang, grammar are universal in humans
• Not a cultural invention (unlike, e.g., computer
  programming, writing)
• Every brain intact person can acquire language
• Does not correlate with IQ, SES, etc
• Intuitively simple sentences (Where did he go?
  The guy I met killed himself) require rule
  systems more complex than any existing computer
  language system can handle

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Grammar instinct (contd)

• No correlation between the complexity of a
  grammar and the degree of technological
  sophistication of a culture
• E.g. English one word for we. Cherokee 4
  words (you I, another person I, several
  other people I, you, one or more other
  persons, I
• Or SES, ethnicity He is working vs. He be
  working (a currently ongoing activity) and He
  working (has a job)
• All human grammars are a subset of all possible
  grammars, and are slight variants on what appears
  to be a universal psychogrammar.

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Language development

• Some milestones

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12 months Gibberish babbling One word utterances
7 months syllable babbling
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2 years, 9 months to 3 years, 6 months all
hell breaks loose stage!
18 months 2 word strings
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Language Acquisition

• By virtue of what cognitive mechanisms do
  children acquire the words of their language and
  its grammar?
• Are the learning mechanisms involved SPECIALIZED
  for language acquisition, or are they designed
  for more general purpose learning?
• Are some features of language acquired via
  language-specific learning mechanisms, and others
  by learning mechanisms with a more general
  function?

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Privileged hypotheses in word learning

• Infinite of hypotheses a problem!
• Quine On another planet, cannot assume beings
  there carve up the world as you do. Can you
  learn the meaning of words? Point to bear, says
  gavagi
• Bear, bear in hat, fur, bear stuff, Bear, gift,
  classroom display, bear or light bulb, bear or
  chair...
• Even worse whenever pointing to bear, you are
  also pointing to an example of
• undivided bear parts, time slice of bear,
  bearhood...

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Privileged hypotheses in word learning

• Child has same problem! Gavagi?!
• Without privileged hypotheses about what kinds of
  things words are likely to refer to, child would
  not be able to learn language at all!
• Other names for Gavagi problem
• Poverty of the stimulus (Chomsky)
• Stim. does not uniquely determine a response
• Combinatorial explosion (Math)
• Frame problem (Artificial intelligence)
• This problem applies to all learning, not just
  word learning

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Some privileged hypotheses in word learning

• Whole object assumption
• Taxonomic assumption
• Mutual exclusivity assumption
• 2-6 years of age learn new word every 2 hours

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Privileged hypotheses in word learning

• Whole object assumption
• Bear, not bear parts or substance.
• Uses object concept system (cohesive, bounded
  entity that moves as a unit)
• Taxonomic assumption
• Basic level object (not superordinate or
  subordinate category)
• Cup (not dinnerware (superordinate) or this
  particular cup (subordinate)

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Privileged hypotheses in word learning

• Mutual exclusivity assumption
• No synonyms
• If child already has a word for the whole object,
  assumes new word refers to something else e.g.,
  to a part or something it is made of
• Point to pewter cup See this, its pewter!
• What else is pewter? pewter tongs, china cup
• If child already knows cup, she picks pewter
  tongs
• If child does not yet have a word for cup, she
  picks the china cup (applies whole object
  assumption)

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Use theory of mind/ joint attention in word
learning

• Show 2 unfamiliar toys, let play
• Put them back in bucket, then take one out for
  baby to play with
• While baby looking at one, YOU look in bucket and
  say, Oh, here is a Toma!
• Ask baby to show/find the toma
• Uses cues from joint attention to tell when you
  are or are not naming something
• Baby does NOT think toma is what SHE was looking
  at
• 16-17 months at chance
• 18-19 months chooses bucket toy

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Grammar acquisition Privileged hypotheses?

• Grammar is learned
• without any explicit instruction
• even in cultures where adults do not speak to
  children who cannot yet talk
• Even though an infinite number of different
  grammars could have produced any set of sentences
  the child might hear.
• Cat v. Tac Plural as mirror reversed?!
• Gavagai again
• So to learn grammar of native language at all,
  must have privileged hypotheses re possible
  rules i.e., psychogrammar

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Language Acquisition Device?? (LAD)

• LAD programs specialized for learning a language
• Switched on early in life, switched off puberty
• Amodal input can be acoustic or visual
• Deaf speakers of American Sign Language
• Same time course as hearing children
• ASL grammar a variant of universal grammar

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Learnability analysis One source of evidence

• Think like an engineer
• Is the proposed learning mechanism capableeven
  in principleof acquiring language
• Proposal Children learn grammatical rules
  through feedback their parents correct their
  grammar when they make a mistake
• But parents rarely correct grammar
• Proposal Children learn language through operant
  conditioning. (General purpose learning)
• Noam Chomsy finite state grammar (the kind of
  grammar that an associationist mechanism would
  have) cannot produce many grammatical sentences
  and would produce many ungrammatical ones

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Learnability analysis One source of evidence

• Proposal Children learn language through operant
  conditioning. (General purpose learning)
• Noam Chomsy finite state grammar (the kind of
  grammar that an associationist mechanism would
  have) cannot produce many grammatical sentences
  and would produce many ungrammatical ones
• I want neither coffee nor tea.
• felt love Bill
  milk love
• I am food fame cup
  food
• want coffee coffee mocha
  you
• went neither you nor
  tea

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Empirical evidence Nim Chimpsky

• Do we learn grammar through operant conditioning?
• If true other animals that can be operantly
  conditioned should learn grammar as easily
• Nim Chimpsky
• No grammar
• Limited vocabulary
• V. smart though

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Empirical evidence Deprivation studies

• What happens if a child is not exposed to a human
  language before puberty?
• Deaf children of hearing parents
• First exposed to ASL (only lang) at different
  ages, tested as adults (30 years of learning)
• Exposed lt 7 ? fine.
• gt 7 many mistakes on function morphemes
  (grammar)
• Other domains (math, biology) longer learning ?
  better performance
• Dont see same effect for grammar

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Is language just the expression of general
ability to manipulate symbols? (i.e., no LAD?)

• Double dissociation between language ability to
  manipulate symbols in other domains
• Stroke damage to Brocas area
• Knock out ability to speak while leaving other
  intellectual abilities intact
• Specific language impairment (SLI)
• Hereditary disorder knock out ability to (e.g.)
  make plurals, past tense (a zag. 2 ___? He
  wugs. Yesterday he ___).
• Can have other functions intact (computer
  programming)
• Williams syndrome. Language fine, but mental
  handicap

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What cues DO children use to acquire their native
grammar?

• Privileged hypotheses ensure they consider only
  some possibilities, not all possibilities
• Of those possibilities, how do they figure out
  which are true of the grammar they are hearing?
• Semantic bootstrapping
• Can word meanings help in grammar learning?
• Syntactic bootstrapping
• Can syntax knowledge help in word learning?

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Semantic Bootstrapping

• Problem How do you learn the syntax of your
  native language? e.g., even if the notion of a
  count noun is grammatically marked in every
  language, how is it grammatically marked in your
  language? (as in a dog.
• Solution Take advantage of a one-way mapping
  from cognition to syntax. For example
• Not all count nouns are objects
• a dog vs a problem, a day
• But all objects are count nouns.
• Not all verbs are actions (kick vs seem)
• But all actions are verbs.

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Syntactic cues to word meaning

• Test 17 month olds, only 2 words in productive
  vocabulary
• Cue Word order
• Big Bird is washing Cookie Monster
• Cookie Monster is washing Big Bird

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Syntactic cues to word meaning

• Cue transitive /intransitive distinction (24
  months)
• Rabbit duck are both moving their arms in
  circles. Rabbit is pushing duck up and down
• Intransitive The rabbit and duck are gorping
• Transitive The rabbit is gorping the duck
• Wheres gorping now? Find gorping!

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Syntax of Verbs, Count Nouns, Mass Nouns

• Picture is of hands in a bowl, kneading confetti
• Verb sytax Do you know what it means to sib?
  In this picture, you can see sibbing.
• Count noun syntax Do you know what a sib is?
  In this paicture, you can see a sib.
• Mass noun syntax Have you seen any sib? In
  this picture, you can see sib.
• Show me another picture of
• Sibbing (choose hands kneading something else)
• A sib (choose bowl)
• Sib (choose confetti)

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Do we learn grammar by word analogy? (i.e.,
ignoring the grammatical category)

• Jane eats chicken
• Jane eats fish
• Jane likes fish (note fish is a noun)
• Jane eats slowly (note slowly is an adverb,
  not a noun)
• Jane might fish (note fish is a verb, might
  is an auxillary)
• WORD analogy would make you think
• eats, likes, might can all go in position 2,
  following subject (Jane)
• chicken, fish, and slowly can all go in position
  3
• (i.e., no distinction between ordinary and
  auxillary verbs in position 2 or between
  adverbs, nouns, and verbs in position 3)
• So you would think the following were
  grammatical
• Jane might slowly WRONG!
• Jane likes slowly WRONG!
• Jane might chicken WRONG!

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Language uses two tricks Words Rules

• Memory Store words
• Regular forms store stems
• Irregular forms store word
• (ran means runpastness)
• Expensive storage, cheap computation
• Use rules
• Add ed to verb stem to make past tense of verb
• Add s to noun stem to make plural
• Requires expensive computation, cheap storage

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Rules applied Evidence from over-regularization
of past tense

• Time course for over-regularization of past tense
• 12 months isolated words
• 18 months 2 word microsentences
• See baby More milk
• 24 months (2 years) Longer, more complex
  sentences, with function morphemes
• -ing, -ed, -s, auxiliaries (have, must)
• After 1.5 and before 3 years Children make
  over-regularization errors
• Goed (went) Runned (ran)
• Mean 4.2, median 2.5

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How does child learn these rules?

• Not through negative evidence e.g., child who
  was unable to talk but was able to understand
  language, could judge perfectly whether a
  sentence was grammatical or not. But he cannot
  have had any negative evidence because he could
  not produce wrong sentences where he could get
  feedback.
• Not imitation or analogy
• Note some verbs are irregular no rule generates
  their past tense form. These are the most common
  verbs (to be, to do, to go, to make, to have, to
  hold...)
• held, went, heard past tense first stored as
  dictionary items, along with regulars played,
  tripped pastness is stored as part of these
  words meaning
• Then the add -ed to stem rule comes on line,
  becomes obligatory

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Why over-regularize?

• Rate of over-regularization very low.
• Sporadic malfunctioning, not qualitative
  difference is system. Same low rate ages 2-5
• Still use irregulars Why not always regularize?
• Blocking rule an irregular idiosyncratic form in
  mental dictionary that corresponds to a
  grammatical modification BLOCKS applicatin of the
  past tense rule
• Memory retrieval the more something is heard,
  easier to retrieve. If slow in retrieving
  irregular form, will sometimes regularize it
• older adults with memory loss over-reg

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Qualitative Change in Learning?

• Are children now learning by analogy on the basis
  of SOUND?
• Test Auxiliary verbs sound like ordinary verb
  forms
• They SOUND identical
• Does child treat them differently even so?
• I.e., Does child respect grammatical category in
  applying rules?

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Qualitative Change?

• e.g., Look what he doed (do ordinary verb)
  but not Look what he doed make (do auxiliary
  form)
• Are children now learning by analogy on the basis
  of sound?
• No.
• Auxiliary ordinary forms SOUND identical, but
  child treats them DIFFERENTLY!
• Past tense rule applied to ordinary verb form
• But not to identical sounding auxiliary verb form
• So what is going on with over-regularization?

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Over-regularization is driving out a different
kind of error bare stem errors

• A bare stem error (no inflection tacked on)
• An over-regularization error
• Note No backsliding or regression
• Over-regularization is replacing another kind of
  error, not correct useage

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Words Rules So why over-regularize?

• Memory retrieval for irregular past tense forms
  not as good when new language learner
• When retrieved, Blocking rule prevents over-reg
• When not, -ed rule applied to bare stem
• Learning by sound analogy not the explanation
• I doed it, not I doed make it
• Creation of new verbs by adults Problem of
  inducing past tense the same as for children
• What happens?

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Words Rules Evidence from adults

• Creation of new verbs by adults
• I wug, I wugged (no irregular form stored)
• What about Verbs derived from a noun stem?
• No past tense for a noun stem
• Hockey stick he was high-sticked (not
  high-stuck)
• It is not a way of getting stuck
• A way of getting hit (by a stick)
• Baseball. A fly. He flied out (not he flew out)
• See same patterns in changes in language over
  time
• As irregular past tense becomes rare, hard to
  retrieve
• Did you chide him? I choad him I chided him

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Language

• Does the child come factory equipped with any
  knowledge of the world?
• What is the difference between studying natural
  competences and side-effects?
• What does learning mean?
• How many learning processes are there?
• Is instinct the opposite of learning?
• What is the design of the instinct that causes
  learning in a given domain?

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Questions to think about throughout 142...

• What does the child know about the world?
• How does the child come to know what she knows?
• Is the childs mind different from the adults
  mind, or does the child just know less?
• Does the child come factory equipped with any
  knowledge of the world?

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Questions to think about throughout 142...

• How does the environment affect development?
• How does maturation affect development?
• Why did scientists underestimate how much infants
  know?
• What is the competence/ performance distinction?
• Can one part of the brain know something that
  another part of the brain does not know?

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Questions to think about throughout 142...

• What is the difference between studying natural
  competences and side-effects?
• What does learning mean?
• How many learning processes are there?
• Is instinct the opposite of learning?
• What is the design of the instinct that causes
  learning in a given domain?