5. EARLY MULTI -WORD SPEECH: NATIVIST APPROACHES Flashcards
nativist approach
assumes that children approach the task of learning language with innate machinery that is specific to language, sometimes described as a language acquisition device or universal grammar
nativists vs constructivists: creativity
N:
Children’s utterances are creative because they have access to innate grammatical rules
C:
Utterances are creative because creativity is based on the use of lexical frames learned from the language children hear, with new items inserted into variable ‘X’ slots
nativists vs constructivists: observation
N:
children observe adult word order because they have an abstract rule
- subject - verb - object
C:
observe adult words order because they pick up high frequency lexical frames from their input
nativists vs constructivists: generalisations
N:
generalisations (adding inflections to words) provide evidence of abstract (innate) rules
C:
generalisations demonstrate that children learn these patterns gradually from distributional analysis of the language they hear
nativist assumptions
- grammar is a symbolic computational system, processing the relationships between abstract variables
- grammatical categories are given apriori in the child’s brain from birth (UG)
- predict that the acquistion of a particular aspect of grammar should have an all or nothing quality (Marcus)
nativist general predictions
Radford:
- once a child able to parse an utterance like “close the door”
- can infer the verb precedes its complement, and the same for others
prediction 1:
children should learn these innately specified aspects of grammar very early on
prediction 2:
children should show consistent treatment of members of a particular grammatical category
principles and paramters of universal grammar (UG)
- all possible rules for languages are innate
- grammar is universal - rules of grammar apply to all languages
- where the rules of grammar differ across languages they do so in highly constrained ways which are encoded by parameters
- children need to work out which parameter settings apply for the lanugage they are learning
examples of parameter settings
word order:
verb - object (Eng), object - verb (Jap)
subject use:
in some languages subjects are obligatory (Eng), in others subjects are optional (Ital)
theoretical advantages of UG
avoids problem of explaining how children acquire complex grammatical rules
allows a unified theory of acquisition across languages whilst explaining how languages differ
empirical evidence for principles & parameters
- children’s early utterances observe adult word order - taken as evidence the relevant paramter is set
- children are productive from early on (allgone sticky)
- children show productive use of some Noun and Verb inflection from age 2.5 and readily combine novel nouns with other words
- some evidence that children understand the role of word order from age 2 years or earlier from preferential looking studies
Preferential looking and poinitng studies
children aged 1;9 can identify the correct picture to match subject-verb-object sentences from a choice of 2 causal actions
(Gertner, Fisher, & Eisengart, 2006)
- taken as evidence for setting the word order parameter
- less clear results for distinguishing non-causal actions described with the intransitive subject-verb construction from causal actions
- disagreement as to what these results mean - comprehension vs. production
theoretical problems for UG
- parameters not clearly specified
- unclear how children avoid setting parameters incorrectly
- bilingualism - how do children set 2 (or more) versions of the same parameters
empirical evidence against principles & parameters
children exhibit limited knowledge of SVO word order in production and act-out studies
naturalistic data studies provide evidence of partial, lexically specific knowledge within a grammatical category - verbs, auxiliaries, determiners
many studies show a close relation between what children hear, how often, and what and when they learn
nativist summary points
- nativist approaches provide an account of children’s early multiword utterances that emphasises their similarity to adult language
- continuity accounts explain dev. in terms of limitations on performance rather than limited knowledge
maturational models
solution to observed ‘development’
- the child has some grammatical knowledge available from birth but other aspects of grammar ‘switch on’ at biologically predetermined points in dev.
- an attempt to explain why children’s early utterances are ungrammatical if children operate with innate grammar
Radford’s (1990) maturational model
at the lexical stage of development (~20m), utterances consist of mainly content words, with other parts of corresponding adult utterance omitted
at the function stage (~24m) the child’s innate grammar ‘matures’, and parts governing the use of more complex grammatical components switch on. e.g., auxiliary verbs, determiners, inflections
Radford, 1990
maturational model advantages + evidence
- explains why early utterances are not fully grammatical
- allows for dev. over time so more likely to fit the empirical data
- fits with possible patterns in other areas of dev. (piaget’s stages of intellectual dev., onset of puberty)
maturational model: theoretical & empirical problems
- difficult to identify precise point in development when functional stage grammatical system comes ‘on-line’
- from earliest stages children show some use of most grammatical functions, although inconsistent
- at around 24 months, children’s use of many ‘functional’ words related to lexical frames (Lieven et al, 1997)
the linking problem
How do children link up their innate knowledge of grammatical categories to the words they are hearing?
- cargegivers dont label words as e.g., nouns
- but UG - what children are hypothesised to have innately - is defined in these terms
semantic bootstrapping
proposed solution to the linking problem
assumes:
- grammatical (syntactic) categories and rules innate
- children use semantics (meaning) to map words in the input onto these innate syntactic categories by using innate linking rules to map semantics onto syntax
can link semantic roles: agent, patient
to syntactic roles
- agent = subject of sentc
- patient = object of sentc
Pinker, 1984; 1989
semantic bootstrapping: distributional analysis
it’s not always easy to work out grammatical categories from meaning
solution:
use a form of distributional analysis to determine word order for the language from proto typical sentences. Then apply knowledge of word order to work out grammatical category of more abstract terms
advantages of semantic bootstrapping
- explains how children break into innate system
- explains why early utterances follow adult word order
- explains how children learn verbs which are not actions, nouns which are not objects etc..
problems for semantic bootstrapping
- many of children’s early lexically- specific utterances are not semantically prototypical, and therefore are unlikley to be based on innate knowledge of semantic linking rules
- in passive sentences, the noun phrase (NP) which is usually the object of an active transitive becomes the subject
passive - the mouse was chased by the cat (opposed to cat chased mouse)
the problem of passives
- if the child hears passive utterances early on, she may use semantic bootstrapping to conclude that her language is object-verb-subject -> problems parsing other utterances
- some nativists propose that the passive ‘parameter’ doesnt mature until later (5y) so passives are learned late
BUT - children do hear and use passive sentences from early on
