Child Language Acquisition

Language Acquisition First Language Acquisition: So far we have looked at various ways of accounting for our phonetic, phonological, morphological, syntactic, semantic and pragmatic competence in our language(s). This gives us some idea of what exactly constitutes our linguistic knowledge. Now maybe we can begin to appreciate just what a child does when s/he learns language: What exactly does a child do? Whatever it is, it's universal -it is acquired regardless of culture, language, class, etc. (e.g. Polish case system is easily learned, Hanunoo color terms, Japanese topic- comment structure, etc.) -it's effortless. Language acquisition occurs in stages: 1) BABBLING (+/- 6 months) -child produces the full range of possible speech sounds-even those which do not occur in speech heard in immediate environment, (the TARGET LANGUAGE) and which s/he may later find "impossible" to reproduce when learning a foreign language. 2) HOLOPHRASTIC / ONE-WORD STAGE: (+/- 12-14 months) -the words produced in holophrastic speech are not just any words. For example you get: cookie drink bad fast go yes/no But never: *in *the *and Remember the distinction? It looks again as though the distinction between OPEN CLASS and CLOSED CLASS words comes into play. This, then is further evidence to the PSYCHOLOGICAL REALITY of that division. These single words may even function as illocutionary acts: May ASSERT/COMMAND/QUESTION. 3) TWO-WORD STAGE (+/- 24 months) -still virtually no closed class words -some pronouns, especially ME/YOU. How can you tell the difference between a two-word utterance and two one-word utterances? -intonation -structure (often N V) 4) TELEGRAPHIC SPEECH (e.g. for English) -no 3-word stage -basically English sentences, but still without closed class items. -some affixes (past tense marker, plural) -SVO word order (almost invariable) -constant changing/adding of rules e.g. Labov and Labov studied their daughter Jessie's acquisition of inversion in Wh-questions: Adult rule of inversion: What do you want? Where have you been? Why are you crying? Who did you see? How will you do that? That is, MODAL/HAVE/BE inverts with subject. Child speech is more likely to contain: What you want? Where you have been? Why you are crying? Who you saw/see? How you will do that? JESSIEat age 3.4: NO inversion 3.5 70% How 30% Where 30% What 10% Why 3.7 80% How 50% Where 40% What 5% Why 3.9 95% How 85% Where 70% What 10% Why 4.5 95% How 95% Where 100% What 50% Why 4.9 100% How 100% Where 100% What 80% Why -Looks as though, initially, there is NO RULE OF INVERSION. -Then a rule is hypothesized, but its domain is limited. -Domain of rule gradually enlarges until it is the same as adults'. In the light of these data, let's consider some hypotheses which have been proposed to account for how a child learns language: -Child memorizes sentences (SILLY) -Child learns by uttering random strings and having only the correct ones reinforced. (The 'behaviorist'/Skinnerian view) -Innate programming Let's look at the Reinforcement Hypothesis: -What ways of reinforcement might be used? -parent DOESN'T say: "I'll give you a bowl of ice cream if you invert subjects with auxiliaries in all your WH- questions." -rather, some parents may CORRECT their children by telling them what they should have said: OVERT POSITIVE REINFORCEMENT. -but, since it's pretty clear that children do not memorize sentences, then we can't suppose that the new "correct" version is just being stored away somewhere. -Rather the child has to hypothesize some kind of rule to account for the new sentence, in order for the correction to have any effect. -Otherwise the correction would hold ONLY FOR THAT TOKEN. -Other types of reinforcement: COVERT POSITIVE: child hears only grammatical strings OVERT NEGATIVE: child is told certain strings are wrong: (flip- side of O.P.) COVERT NEGATIVE: child doesn't hear ungrammatical strings. So we get a picture of the child as RULE HYPOTHESIZER: -INPUT = linguistic data i.e. speech heard around child's environment -OUTPUT = rules in child's mind. What must the kid start with to do this? Preprogramming? The observable chain of events is: 1) Child is born: no language. 2) Child receives input/stimuli. 3) Voila! Child acquires language. How much is acquired and how much is preprogrammed? Well, what if the stimuli are varied? Then, if language learning depends solely on environmental input, the learning process should also differ: Method: Find kids who, for some reason or other, lack certain types of input: 1) Blind child: Kelli (Lila Gleitman and Barbara Landau) -Original claim: Blind children are 6 months later (on the average) than seeing children in acquiring language. Kelli: Not late at all, above average, in fact. -only deviation was found in her acquisition of visual terms: COLOR TERMS: she knew that color is a property of concrete objects. e.g. that you can say "red ball" but not "red birthday party" LOOK: has a different semantic range for Kelli: e.g. LOOK UP (reaches up with her hands) vs. SEE Turns out that the reason blind children are on the average 6 months later than sighted children in acquiring language is that the vast majority of blind children at that time were blinded immediately following birth by oxygen administered because they were on the average 3 months premature. If children who were born 3 months prematurely but were not blinded are studied, it turns out that they too are about 6 months late in acquiring language! Thus the lateness seems to be due to the fact that the nervous system is not quite 'done' when the child is born and has nothing to do with blindness. 2) Deaf child, in a signing environment (Laura Petitto) -Child goes through PRECISELY the same stages as a hearing child, except the modality is manual/visual instead of oral/aural. 3) Deaf child, in an oral language environment: severe deficit, irremediable if allowed to persist too long 4) Two deaf children (twins) in an oral environment: invent their own sign language! (Lila Gleitman) 5) Seeing/hearing child deprived of linguistic stimuli: Genie (Vicki Fromkin and her students) Severe deficit, irremediable.