PSY 369: Psycholinguistics

1. PSY 369: Psycholinguistics Language Acquisition

2. Announcements http://www.routledge.com/cw/harley-9781848720893/s1/students/ • Exam 2 moved to March 6th (the Thursday before Spring Break). • Some other due dates have shifted: • Quiz 4, moved back a week (now Feb 28th) • Hmwk 3, moved to (Feb 27th) • Bonus videos (1 hr broken into 6 parts): • Why do we talk? The science of speech: part 1 (language acquisition recording 3 years of language in a household) • Part 2 (chimps & language, language & brain) • Part 3 (language & brain cont., infant speech perception) • Part 4 (language and autism, language innateness [Chomsky], wild children) • Part 5 (language in birds, language in our genes) • Part 6 (language and evolution, learning artificial languages)

3. Overview • General patterns and observations • Learning sounds • Perception (e.g., categorical perception) • Production • Learning words • Meaning • Proposed Strategies • Fast mapping • Whole object • Mutual exclusivity • Learning Syntax • Learning Morphology Today’s focus

4. Language explosion continues • The language explosion is not just the result of simple semantic development; the child is not just adding more words to his/her vocabulary. • Child is mastering basic syntactic and morphological processes.

5. Language explosion continues • Syntax • Mean length of utterance (MLU) in morphemes

6. Language explosion continues • Syntax • Mean length of utterance (MLU) in morphemes • Take 100 utterances and count the number of morphemes per utterance Daddy coming. Hi, car. Daddy car comed. Two car outside. It getting dark. Allgone outside. Bye-bye outside. # morphemes: 3, 2, 4, 3, 4, 2, 2 ‘-ing’ and ‘-ed’ separate morphemes ‘allgone’ treated as a single word MLU = morphemes/utterances = 20/7 = 2.86

7. Language explosion continues • Proto-syntax (??) • Holophrases (around 1-1.5 years) • Single-word utterances may be used to express more than the meaning usually attributed to that single word by adults “dog” might refer to the dog is drinking water • Typically idiosyncratic, but some conventional/common (e.g., indicate the existence of an object, request recurrence of object or event) • Often combined with intonation or gesture • Controversial claim: May reflect a developing sense of syntax, but not yet knowing how to use it (e.g., see Bloom, 1973)

8. Language explosion continues • Syntax • Roger Brown (1973) proposed 5 stages • Stage 1: Telegraphic speech (MLU ~ 1.75; around 24 months) • Children begin to combine words into utterances • Limited to a small set of semantic relations (e.g., nomination, recurrence, attribution, possession [see textbook table 4.5]) • Debate: learning semantic relations or syntactic (position rules) • “baby sleep” agent+action or Noun Verb • Children in telegraphic speech stage are said to leave out the ‘little words’ and inflections: • e.g. Mummy shoe NOT Mummy’s shoe • Two cat NOT two cats

9. Language explosion continues • More than two words • Stages 2 through 5 • Stage 2 (MLU ~2.25) • begin to modulate meaning using word order (syntax) • Modulations for number, time, aspect • Gradual acquisition of grammatical morphemes (“-ing”, “-s” • Later stages reflect generally more complex use of syntax (e.g., questions, negatives) • Syntax • Roger Brown (1973) proposed 5 stages

10. Acquiring Syntax • General Theoretical Approaches • Innateness accounts • Universal grammar, Semantic bootstrapping • Learned accounts • Acquired from the linguistic input from the environment • Need to acquire (at least) two things: • The syntactic categories of the words (nouns, verbs, etc.) • How to order the words (or the syntactic categories)

11. Acquiring Syntax • Innateness account • Chomsky proposed that we have an innate facility for language • Universal grammar: the rules that describe the fundamental properties of all natural human languages • Chomsky’s arguments • The rules that underlie productive language use are highly abstract and largely “unobservable” • We can understand and produce novel utterances (things that we’ve never heard or said before) • Poverty of the stimulus: The gap between what language users know and what they have access to during learning is too broad • Negative evidence: children rarely receive explicit feedback about incorrect grammatical utterances

12. Acquiring Syntax • Innateness account • Semantic bootstrapping – use meaning to help learn syntax • e.g., Pinker (1984, 1989) • Child has innate • knowledge of • syntactic categories • and linking rules: • Nouns, and Verbs • Thematic roles (Agents, • Patients) Child learns the meanings of some content words “Doggie”“eat”“ball” Child constructs some semantic representations of simple sentences “Doggie eats the ball.” Child makes guesses about syntactic structure based on surface form and semantic meaning “Doggie” is N, subject “eats” is V, predicate “ball” is N, object

13. Acquiring Syntax • Some problems with this account (e.g., Bowerman, 1990; Gleitman, 1990) • Do kids really enough utterances with identifiable agents and patients that can be mapped onto nouns and verbs (verbs are especially hard)? • Many words appear as both nouns and verbs (e.g., “go for a walk” & “walk out the door”). • Easier mappings aren’t always learned earliest (e.g., verbs like “fall” and “chase” have themes that map onto the sentence subject. This should be simpler than verbs like “have” and “got” in which the them maps onto the object) • Innateness account • Semantic bootstrapping – use meaning to help learn syntax • e.g., Pinker (1984, 1989)

14. Acquiring Syntax • Learned account • “It is in the stimulus” accounts (e.g. Bates, 1979, Elman, 1993) (Statistical learning, Usage-based approaches) • Speech to children is not impoverished (Snow, 1977) • In all languages there are multiple potential cues indicating semantic/syntactic relations (e.g., word order, case marking) • Similar words occur in similar linguistic contexts • Acoustic information (e.g., prosody) may provide syntactic cues (phonological bootstrapping) • Children do not need innate knowledge to learn grammar (evidence largely from successful computer models)

15. Acquiring Morphology • Morphology • Typically things like inflections and prepositions start around MLU of 2.5 (usually in 2 yr olds) • Remember the Wug experiment (Berko-Gleason, 1958)

16. Acquiring Morphology • Morphology This person knows how to rick. She did the same thing yesterday. Yesterday she ________. Typically children say that she “ricked.”

17. Acquiring Morphology • Morphology: order of acquisition

18. Acquiring Morphology • Children sometimes make mistakes. My teacher holded the baby rabbits. Yes She holded the baby rabbits. No, she holded them loosely. Did you say your teacher held the baby rabbit? What did you say she did? Did you say held them tightly?

19. Acquiring Morphology • Children sometimes make mistakes. • This is ungrammatical in the adult language • Shows that children are not simply imitating • In this case, what they produce something that is not in their input. My teacher holded the baby rabbits.

20. Acquiring Morphology • Children sometimes make mistakes. • Why do they make errors like these? • In the case at hand, we have what is called overregularization • The verb hold has an irregular past tense form, held • Because this form is used, the regular past tense-- that with -ed-- is not found (*hold-ed) My teacher holded the baby rabbits.

21. Acquiring Morphology • Examples: • Horton heared a Who • I finded Renée • The alligator goed kerplunk • The case of verb past tense: • Regular verb forms require no stored knowledge of the past tense form (wug test) • Past tense is accomplished by applying a past tense rule (e.g., add -ed) to the verb stem • With irregular verbs something must be memorized

22. Acquiring Morphology • Stages in the acquisition of irregular inflections • The case of verb past tense: • With regular verbs, the default form -ed is used • With irregulars, lists associating the verb with a particular form of the past tense have to be memorized: • Past tense is -t when attached to leave, keep, etc. • Is -> was • Dig -> dug • Has -> had

23. Acquiring Morphology • Stages in the acquisition of irregular inflections time • On the face of it, learning these morphological quirks follows a peculiar pattern: • Early: correct irregular forms are used • Middle: incorrect regular forms are used • Late: correct forms are used again

24. Memory & Rules • Why do we find this type of pattern? • Memory and rules • The use of overregularized forms starts at around the same that that the child is beginning to apply the default -ed rule successfully • Early: All forms-- whether regular or irregular-- are memorized • Middle: The regular rule is learned, and in some cases overapplied • Late: Irregulars are used based on memory, regulars use the rule (the idea is that if the word can provide its own past tense from memory, then the past tense rule is blocked)

25. Memory & Rules • Why do we find this type of pattern? • Memory and rules • Other accounts • Maratsos (2000) – frequency explanation • It is possible to predict which verbs will be subject to overregularization • The more often an irregular form occurs in the input, the less likely the child is to use it as an overregularization • This is evidence that some part of overregularization occurs because of memory failures • Something about irregulars is unpredictable, hence has to be memorized

26. What kind of “teaching” do kids get? • If language is learned (and not innate), how do kids do it? • What kind of feedback do they get? • Claim: Positive evidence is not sufficient for learning a language.

27. What kind of “teaching” do kids get? • Are the kids even aware of mistakes? • The children are apparently aware of the fact that their forms are strange: • Parent: Where’s Mommy? • Child: Mommy goed to the store • Parent: Mommy goed to the store? • Child: NO! Daddy, I say it that way, not you

28. Positive and negative evidence • Positive evidence: Kids hear grammatical sentences • Negative evidence: information that a given sentence is ungrammatical • Kids are not told which sentences are ungrammatical(no negativeevidence) • Let’s consider no negative evidence further… • What kind of feedback is available for learning?

29. What kind of “teaching” do kids get? • How much Positive Evidence is there? • Estimated 5000 – 7000 utterances a day • Between ¼ and 1/3 are questions • Over 20% are not “full” adult sentences (typically Noun or prepositional phrases) • Only about 15% have typical English SVO form • Roughly 45% of all maternal utterances began with one of 17 words (e.g., “what”, “that”, “it”, “you”) Cameron-Faulkner, et al (2003) • So what kids do hear may be somewhat limited.

30. Negative evidence • Negative evidence could come in various conceivable forms. • “The sentence Bill a cookie ate is not a sentence in English, Timmy. No sentence with SOV word order is.” • Upon hearing Bill a cookie ate, an adult might • Not understand • Look pained • Rephrase the ungrammatical sentence grammatically

31. Kids resist instruction… McNeill (1966) • Child: Nobody don’t like me. • Adult: No, say ‘nobody likes me.’ • Child: Nobody don’t like me. [repeats eight times] • Adult: No, now listen carefully; say ‘nobody likes me.’ • Child: Oh! Nobody don’t likes me.

32. Kids resist instruction… Cazden (1972) (observation attributed to Jean Berko Gleason) • Child: My teacher holded the baby rabbits and we patted them. • Adult: Did you say your teacher held the baby rabbits? • Child: Yes. • Adult: What did you say she did? • Child: She holded the baby rabbits and we patted them. • Adult: Did you say she held them tightly? • Child: No, she holded them loosely. • So there doesn’t seem to be a lot of explicit negative evidence, and what there is the kids often resist

33. Negative evidence via feedback? • Do kids get “implicit” negative evidence? • Do adults understand grammatical sentences and not understand ungrammatical ones? • Do adults respond positively to grammatical sentences and negatively to ungrammatical ones?

34. Negative evidence via feedback? Brown & Hanlon (1970): Case study of “Adam” - looked at things that were said to him by adults, and what he said to them • Adults understood 42% of the grammatical sentences. • Adults understood 47% of the ungrammatical ones. • Adults expressed approval after 45% of thegrammatical sentences. • Adults expressed approval after 45% of the ungrammatical sentences. Suggests that there isn’t a lot of good negative evidence.

35. In a way, it’s moot anyway… • One of the striking things about child language is how few errors they actually make. • For negative feedback to work, the kids have to make the errors (so that it can get the negative response). • But they don’t make enough relevant kinds of errors to determine the complex grammar. • Pinker, Marcus and others, conclude that much of this stuff must be innate. • But this isn’t the only view. There is an ongoing debate about whether there are rules, or whether these patterns of behavior can be learned based on the language evidence that is available to the kids

36. Critical (sensitive) periods

37. Critical (sensitive) periods • Certain behavior is developed more quickly within a critical period than outside of it. This period is biologically determined. • Examples: • Imprinting in ducks (Lorenz, ; Hess, 1973) • Ducklings will follow the first moving thing they see • Only happens if they see something moving within the first few hours (after 32 hours it won’t happen) of hatching • Binocular cells in humans • Cells in visual system that respond only to input from both eyes. • If these cells don’t get input from both eyes within first year of life, they don’t develop

38. Critical (sensitive) periods • Certain behavior is developed more quickly within a critical period than outside of it. This period is biologically determined. • Some environmental input is necessary for normal development, but biology determines when the organism is responsive to that input. • That “when” is the critical period

39. Critical period for language • Lenneberg (1967) proposed that there is a critical period for human language • It assumes that language acquisition must occur before the end of the critical period • Estimates range from 5 years up to onset of puberty

40. Evidence for critical period for language • Feral Children • Children raised in the wild or with reduced exposure to human language • What is the effect of this lack of exposure on language acquisition? • Two classic cases • Victor, the Wild Boy of Aveyron • Genie

41. Victor, The Wild Boy of Aveyron • Found in 1800 near the outskirts of Aveyron, France • Estimated to be about 7-years-old • Considered by some to be the first documented case of autism • Neither spoke or responded to speech • Taken to and studied by Dr. Jean-Marc-Gaspard Itard, and educator of deaf-mute and retarded children • Never learned to speak and his receptive language ability was limited to a few simple commands. • Described by Itard as “an almost normal boy who could not speak”

42. Genie • Found in Arcadia, California in 1970, was not exposed to human language until age 13.5. • Raised in isolation a situation of extreme abuse • Genie could barely walk and could not talk when found • Dr. Susan Curtiss made great efforts to teach her language, and she did learn how to talk, but her grammar never fully developed. • Only capable of producing telegraphic utterances (e.g. Mike paint or Applesauce buy store) • Used few closed-class morphemes and function words • Speech sounded like that of a 2-year-old

43. Genie • By age of 17 (after 4 years of extensive training) • Vocabulary of a 5 year old • Poor syntax (telegraphic speech mostly) • Examples • Mama wash hair in sink • At school scratch face • I want Curtiss play piano • Like go ride yellow school bus • Father take piece wood. Hit. Cry.

44. What Do These Cases Tell Us? • Suggestive of the position that there is a critical period for first language learning (in particular for syntax and phonological development) • If child is not exposed to language during early childhood (prior to the age of 6 or 7), then the ability to learn syntax will be impaired while other abilities are less strongly affected • Not uncontroversial: Victor and Genie and children like them were deprived in many ways other than not being exposed to language • Genie stopped talking after age 30 and was institutionalized shortly afterward (Rymer, 1993)

45. What Do These Cases Tell Us? • Suggestive of the position that there is a critical period for first language learning (in particular for syntax and phonological development) • Why? • Nativist explanation (see pg 79 of text) • Maturational explanation: “less is more”

46. Second language learning • Learning a new language • What if we already know one language, but want to learn another? • Adults learning another language typically have a persistent foreign accent – perhaps a critical period for phonology (Flege & Hillenbrand, 1984) • Adults typically do better initially at learning a new language compared to kids, but kids typically do better over the long term (Krashen, Long, & Scarcella, 1982)

47. Second language learning • Johnson and Newport (1989) • Native Chinese/Korean speakers moving to US • Task: Listen to sentences and judge whether grammatically correct R = -.87 Test score 2 17 Age of arrival R = -.16 Test score 17 40 Age of arrival

48. Second language learning • Johnson and Newport (1989) • Native Chinese/Korean speakers moving to US • Task: Listen to sentences and judge whether grammatically correct • Concluded that around the age of 16 something happens • Different factors operate on language acquisition before and after the age of 16 • Birdsong and Molis (2001) • Replicated the Johnson and Newport study in Spanish/English speakers. • Did not find a discontinuity around the age of 16

49. Effects of the Critical Period • Learning a language: • Under 7 years: perfect command of the language possible • Ages 8- c.15: Perfect command less possible progressively • Age 15-: Imperfect command possible • But these claims are far from universally accepted

50. Bilinguals & Polyglots • Many people speak more than one language • Tucker (1999) - multilinguals outnumber monolinguals • What is the impact of knowing/using more than one language? • Factors affecting second language acquisition? • What does the lexicon look like? • Interesting effects in bilinguals • Interference • Code switching • Cognitive advantages