phonological$processing$ thisweek$ …creel/cogs156/cogs156_files/lectures7-9.pdf ·...

4/11/11

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Phonological processing

At school, where every teacher was a poten8al spy, I tried to avoid an s sound whenever possible. "Yes," became "correct," or a military "affirma8ve." … ACer a few weeks of what she called "endless pestering" and what I called "repeated badgering," my mother bought me a pocket thesaurus, which provided me with s-‐free alterna8ves to just about everything. …

Plurals presented a considerable problem, but I worked around them as best I could; "rivers," for example, became either "a river or two" or "many a river." Possessives were a similar headache, and it was easier to say nothing than to announce that the leC-‐hand and the right-‐hand glove of Janet had fallen to the floor.

-‐-‐David Sedaris, Me Talk Pre*y One Day

This week

•  More about what kids perceive •  Then, back to what they produce

Suprasegmental proper8es

•  Stress – Melon vs balloon-‐-‐applies to whole syllable, not segment (phone)

•  Intona8on – Applies over mul8ple words

-‐20 0 20 40 60 80

Voiced Voiceless

VOT (ms)

English speakers can dis8nguish synthesized b/p sounds differing only in VOT, if tested using 20 and 40 msec.

But they can’t (or perform poorly) if tested using 0 and 20 or 40 and 60.

Categorical percep<on (strict defini8on): listeners can only discriminate sound pairs they can give different labels.

Categorical percep<on (loose defini8on): listeners are much be_er at discrimina8ng between categories than within categories.

-‐20 0 20 40 60 80

Voiced Voiceless

VOT (ms) * *

√

* *

X

* *

X

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How do infants perceive speech sounds? Eimas et al.: 1-‐ and 4-‐month-‐olds; habitua8on procedure.

+20/+40 (ba/pa)

0/+20, +60/+80

Control (ba…ba…ba…ba…)

VOT:

√ X

Property of auditory system[s] to pick up on this boundary

chinchilla macaque J. quail

Basic auditory ability

Further study: replica8ons tes8ng discrimina8on of many speech sounds.

Under ideal condi8ons, young infants can tell apart any two speech sounds that are used in any language for conveying different meanings.

big/pig

shed/said

dumb/numb

ñora/nora

some contrasts some contrasts infants discriminated in studies

b/p b/d r/l b/w b/m w/j

s/z s/0 f/0 d/g

a/i u/y a/ã E/æ i/I

-‐ -‐

language-‐specific refinement

Werker & Tees 1984: test discrimina8on of Hindi dental and retroflex /t/, and discrimina8on of Nthlakampx velar and uvular consonants [k’] and [q’], using CHT.

Canadian babies: discriminated at 6-‐8 months only some did at 8-‐10 months almost none at 10-‐12 months

Infants get worse at discrimina:ng sounds that aren’t contras:ve in their language.

velar uvular

language-‐specific refinement: vowels

similar results, perhaps even earlier development

Polka & Werker 1994, using visual habitua8on procedure

German /u/ vs /y/ 4 months discriminate 6 months don’t 1 12 months don’t

Catalan and Spanish

Catalan: has /e/ and /E/ (like “bait” and “bet”) Spanish: just something in between, near /e/

Bosch & Sebas8an-‐Gallés, using habitua8on procedure:

all 4.5 month olds discriminate /e/ and /E/; Catalan 8.0 month olds discriminate them too; Spanish 8.0 month olds don’t AND bilinguals don’t; Bilinguals discriminate again, by 12 months.

language-‐specific refinement: vowels

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Produc8on follows percep8on

•  Very likely that children can perceive contrasts before they can produce them

•  Perceptually, kids can dis8nguish all sorts of sounds early on

•  Gradually narrow down to own language •  Produc8on of language-‐specific sounds takes much longer –  Needs motor prac8ce to get motor control

Percep8on takes some 8me

•  Some sound boundaries you’re born with (VOT dis8nc8on)

•  Others are more language-‐variable and may require more learning –  Dis8nguishing all sounds may not be good-‐-‐ –  Need some similarity to build on

•  Knowing individual sounds isn’t the same as knowing which ones go together in words

•  Learning words as labels for things may make percep8on harder


•  Boundaries you’re born with (VOT dis8nc8on) •  Learning category boundaries •  Learning which sounds go together •  Learning words as labels – This is the point of it all, isn’t it? – Similar words are hard to learn

✔

Category boundaries

•  Maye, Werker, & Gerken, 2002 •  Newman, Clouse, Burnham 2001

Maye, Werker, & Gerken (2002)

•  Two distribu8ons or one distribu8on of speech sounds

•  Incidental exposure to one or other

•  Play two sounds from same/different distribu8ons

•  Infants, 6 & 8 months •  (Adults can do too) •  Two-‐lumps: different! •  One-‐lump: not different!

-20 0 20 40 60 80 Speech dimension

Newman, Clouse & Burnham, 2001

•  Frica8ves show these distribu8ons as well

•  Some contextual varia8on

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✔

✔

What ARE they thinking? (A Q&D tutorial on infant methods)

Headturn Preference Procedure: What seems interesting?

1.  trial starts with green light 2.  once baby’s ready, flash one side light 3.  when baby turns to light, start playing sounds from

speaker 4.  when baby turns away, stop sounds and start new

trial

dependent measure: listening time to a given kind of auditory material

Sounds that go together

•  Saffran •  Jusczyk & Johnson •  Nonadjacent dependencies

Cues to word boundaries

•  Stress – English: most nouns are stress-‐ini8al

– ThePRE_yBAbyWANTSaBOTtle


•  Strong-‐ini8al vs. weak-‐ini8al words – Strong: BUTter, CANdle, PUPpy, SAUsage – Weak: baNAna, caBOOSE, reCLINE, aGREE

•  Cutler and colleagues: “metrical segmenta8on strategy” (MSS) – Strong syllable is the start of a word


•  Jusczyk, Houston & Newsome – 7.5. Months: •  Familiarize infants with stress-‐ini8al words

–  Kingdom, hamlet

•  Play passages with kingdom, hamlet (or doctor, candle)

•  Infants listen longer to kingdom/hamlet passages: they recognize the words

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•  Jusczyk, Houston & Newsome – 7.5. Months: •  Stress-‐ini8al OK


•  Jusczyk, Houston & Newsome – 7.5. Months: •  Stress-‐ini8al OK •  Familiarize with guitar, surprise

•  Test with guitar, surprise, balloon, device •  No difference in looking 8mes


•  Jusczyk, Houston & Newsome – 7.5. Months: •  Stress-‐ini8al ✔ •  Stress not ini8al ✘


•  Jusczyk, Houston & Newsome – 7.5. Months: •  Stress-‐ini8al ✔ •  Stress not ini8al ✘

•  Familiarize with tar, prize, loon, vice •  Play guitar/surprise-‐-‐get it


•  Jusczyk, Houston & Newsome – 7.5. months: •  Stress-‐ini8al (kingdom) ✔ •  Stress not ini8al (guitar) ✘

•  Stressed syllable (tar) ✔


•  Jusczyk, Houston & Newsome – 7.5. months: •  Stress-‐ini8al (kingdom) ✔ •  Stress not ini8al (guitar) ✘

•  Stressed syllable (tar) ✔

– 10.5 months: •  Stress not ini8al (guitar) ✔

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But…

•  Not all languages have this kind of stress pa_ern.

•  How do you know what the proper:es of words are if you don’t know what the words are?

•  Looka_hepre_ybaby

•  Looka_hepre_ybaby •  Whereisthebabynowpre_ygirl

•  Thisroastedbabyispre_ygood





•  Given “ty”, what’s likely to come next?



•  Given “ty”, what’s likely to come next?

•  What about given “ba”?

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Let’s do some math…

•  pago8numabékolifudé •  panumalifubékogo8dé

•  palifunumago8békodé

•  …

•  Given “pa”, what’s likely to come next?

•  What about given “go” or “8”?

Sta8s8cal learning

•  Saffran, Aslin & Newport (1996) – 8-‐month-‐old infants

golabubidakutupiropado8tupirobidakupado8golabupado8bidakugolabutupiro golabupado8tupirobidakupado8bidakutupirogolabupado8bidakugolabutupiro …

Sta8s8cal learning



Sta8s8cal learning



Sta8s8cal learning



Sta8s8cal learning

•  Play for 2 minutes •  Present kids with bidaku or piro.bi type words •  What do they listen to longer? bidaku < piro.bi –  (novelty preference)

•  At 8 months infants can segment words based on sta<s<cal cues

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But what about stress?

•  Johnson & Jusczyk (2001) – 8-‐month-‐olds – Stress vs. sta8s8cs: Stress wins



•  Thiessen & Saffran (2003) – Sta8s8cs wins @ 7 mos – Stress wins @ 9 mos



•  Thiessen & Saffran (2003) – Sta8s8cs wins @ 7 mos – Stress wins @ 9 mos

•  Segmenta<on precedes stress.

Sta8s8cal learning

•  What’s ge~ng learned? – Frequency •  Thedog, thegirl > hassock, 8pple

– Condi<onal probability •  Given X, Y is __ likely to happen •  Predic<veness

•  Aslin, Saffran & Newport (1996)

Sta8s8cal learning

•  What’s ge~ng learned? – Aslin, Saffran & Newport (1996) •  golabu/pado8 2x as oCen as tupiro/bidaku •  So do8.go is as frequent as bidaku (45x each) •  But

bi-‐>da-‐>ku

do-‐>8-‐>go

1.0 1.0

1.0 .33

Sta8s8cal learning

•  What’s ge~ng learned? – Aslin, Saffran & Newport (1996) •  golabu/pado8 2x as oCen as tupiro/bidaku •  So do8.go is as frequent as bidaku (45x each) 3 min of listening; then test

bi-‐>da-‐>ku

do-‐>8-‐>go

1.0 1.0

1.0 .33

Frequency:

=

Cond. prob.:

<

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Sta8s8cal learning

•  Infants are indeed learning condi8onal probabili8es, not just frequency.

Language specificity?

•  Works for language •  Works for tone sequences (C-‐C#-‐G…)

•  Works for visual stuff

•  Tamarin monkeys do it (Hauser et al.)

•  Not just a language-‐specific phenomenon.



✔

✔

✔

Sound learning vs. word learning

•  Speech sounds: – Start out hearing everything, – Narrow in on na8ve language by 12 months.

•  Words: – Produce badly at 12 months, – But presumably underlying representa8ons are good.

…Or are they?

Stager & Werker, 1997

“bih” “dih” Test: “dih” 14 mos: no dishabituation!

“Switch” procedure (fancy dishabitua8on)

Dumbed-down: one object 8 mos: ✔ 14 mos: ✘

14 mos: lif vs. neem ✔

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“bih” “dih” WHY??

Perceptual regression? Divided attention?

Unfamiliarity of words?

Stager & Werker, 1997 “Switch” procedure (fancy dishabitua8on) Stager & Werker 1997

•  AHer learning speech sounds, 14-‐month-‐olds seem not to use!

•  S&W: maybe for word learning, kids don’t use detail

•  Swingley & Aslin: maybe they just have poor representa8ons of “bih” and “dih”-‐-‐what about real words?

one simple word recognition task: picture fixation

Swingley & Aslin, 2000, 2002

Where's the ball? "Correct"Where's the gall? "Mispron."

prop

ortio

n to

targ

et"

0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

1

400 450 500 550 600 650 700 750 Age (days)

correct pronunciations mispronunciations

Target fixation given correct pronunciation and mispron., plotted by child’s age

<- 50% = can’t tell

% better on correct pron. than on mispronunciation, shown by child’s production vocabulary (14-23 months)

-40

-20

0

20

40

1 10 100 1000

words in productive vocab.mispronunciation effect (%)

corre

ct -

mis

pron

."

Just because they can’t say it doesn’t mean they can’t hear it

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•  Boundaries you’re born with (VOT dis8nc8on) •  Learning category boundaries •  Learning which sounds go together •  Learning words as labels – New words: weaker representa8ons – Over the long term: good representa8ons

✔

✔

✔

✔

At school, where every teacher was a poten8al spy, I tried to avoid an s sound whenever possible. "Yes," became "correct," or a military "affirma8ve." … ACer a few weeks of what she called "endless pestering" and what I called "repeated badgering," my mother bought me a pocket thesaurus, which provided me with s-‐free alterna8ves to just about everything. …

Plurals presented a considerable problem, but I worked around them as best I could; "rivers," for example, became either "a river or two" or "many a river." Possessives were a similar headache, and it was easier to say nothing than to announce that the leC-‐hand and the right-‐hand glove of Janet had fallen to the floor.

-‐-‐David Sedaris, Me Talk Pre*y One Day

On the ‘output’ side…

•  Sounds kids make: •  Pre-‐6 months: mostly vowels, some back consonants (velars)

•  Later (canonical babbling starts): wider range of places of ar8cula8on –  Regardless of language, kids seem to be making very similar sounds (un8l a li_le while before words appear)

–  Consonants mostly: ptk bdg mn wj s h (Locke ‘83) •  Kids build on these to say first words

Babbling to words

•  Is there a link? Yes! •  Kids who prefer certain babbling pa_erns end up with those pa_erns –  Vocal motor schemes (Vihman 1996) –  Can voluntarily produce matching words

•  Babbling frequency predicts # & accuracy of words produced at 2-‐3 years

•  Late in prespeech, start to drop out sounds that aren’t in child’s language, and adopt rhythms of na8ve language

First words

•  Some: resemble adult words in sound and social context (hi, byebye, peekaboo)

•  Others: made up by kid but used for par8cular func8on-‐-‐protowords –  Controls vocal apparatus? ✓

–  Knows words have specific meanings? ✓ –  Knows that you have to figure out the words that everyone else uses? ✗

–  (Some variability in form)

Acquiring your language’s sound system

•  Not simple adding on of perfectly-‐pronounced words.

•  Some8mes pronuncia8ons change for the be_er or worse.

•  Sounds can show up on some words, but not others.

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•  Regression: sounds get “worse” (Menn 71)

•  Down & stone: /dæwn/ /don/ oral V nasal •  Later, new oral V nasal words: •  Beans & dance: /minz/ & /næns/ –  nasal assimila8on

•  “Took over” more accurate forms of down and stone, which became /næwn/ & /non/


•  Progressive phonological idiom: some words are accurate “too early”

•  No /h/ except on hi and hello •  Others: ‘orse, ‘ose, ‘amster… •  So has he acquired /h/ or not?


•  How to account for regression? Think of child as problem-‐solving (Ferguson & Macken ‘83): How do I sound like the people around me?

•  Temporary solu8ons: –  Avoidance of hard sounds/sequences (Sedaris’ s) –  Exploita8on of sounds you like –  Replacement of one sound with another (/wɛw/) –  Rearrangement of sounds in word (/pəskɛ8/) –  One word, or approximate whole phrase (Peters, 1977)

•  These solu8ons pervade much of cogni8ve and language development


•  Varia:on of these strategies –  Across languages –  Across children –  Tendencies, not absolutes


•  Other influences that aren’t strategic •  Biological constraints

–  For instance: stops [physically] easier than frica8ves •  Perceptual feedback

–  Can’t do much if you don’t have an acous:c model from adults and internal feedback

–  E.g. if you’re hearing-‐impaired-‐-‐external feedback •  Internal feedback=electric fence (immediate) •  External feedback=poison oak (delayed, relies on other person)

–  Internal reward for sounding like those around you

Normal progression

•  Age 3: vowels and many consonants –  Tough consonants: r, l, v, th, dth

•  Should be intelligible by 4 –  Not? Possibly atypical development

•  By age 8: mostly adultlike sounds –  But slower speech rate – More variable pronuncia8on, 8ming

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Describing kids’ pronuncia8ons

•  Ways to describe: – Rules to translate adult form into kid form •  E.g. “delete /s/ in clusters”

– Describe kid’s limita8ons in terms of constraints (e.g. “no clusters”)

– Preferred forms as templates (CVC)

•  Make sense of seemingly-‐unrelated errors


•  Caveat: what we hear is filtered through our own phonological system!

•  Fine-‐grained analyses (Macken & Barton ‘80) – Maybe we can’t hear a dis8nc8on they’re a_emp8ng to make

•  Need for mul8ple measurements of same word @ given age –  Kids gradually add in, correct sounds –  Phases where new form coexists with old one

Inherent variability

•  Cau8on in mispronuncia8on: referen:al vs. expressive style –  Say one word perfectly (referen8al) –  Say approxima8on of whole sentence (expressive)

•  Hard to transcribe!

•  Regional variants in pronuncia8on –  Define correctness by dialect being acquired

•  Variants in contexts: reading list vs. casual conversa8on


•  Things that are tough –  Clusters –  Coda (end of syllable) consonants


•  Things that are tough –  Clusters –  Coda (end of syllable) consonants Relatedly, some languages

don’t have these! Also not found in babbling


•  Things that are tough –  Clusters –  Coda (end of syllable) consonants –  Long words –  Ini8al weak syllables

Relatedly, some languages don’t have these! Also not found in babbling

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•  Things that are tough –  Clusters –  Coda (end of syllable) consonants –  Long words –  Ini8al weak syllables

•  Various solu8ons… –  Sock –  Spock –  School –  String

Omit /s/ Omit other Assim. place

Relatedly, some languages don’t have these! Also not found in babbling


•  Word stress •  Weak-‐ini8al words are hard – Tomato “mato” – Surprise “prize” – Dessert “zert”

•  Not just word length – Blanket “banket” – Puppy “puppy”


•  Assimila:on •  Changing one thing to match another •  Happens in adult speech too –  Green peas-‐-‐> /grimpiz/

•  With kids, more extreme – Well -‐-‐> /wɛw/ –  Cat, dog, pug -‐-‐> /tæt/ /gag/ /kʌg/ – Mump, means, nance-‐-‐>nasal feature spreads backward

Word templates

•  AKA “canonical forms” Vihman & CroC, 2007

•  Between 5-‐100 words, most are variants on a few templates, plus a few isolated phonological idioms

•  Similar adult words that are performed by child from same template –  Fish dish vest brush fetch –  ɪʃ dɪʃ ʊʃ byʃ ɪʃ –  Pa_ern: (C)Vʃ

•  Rules change adult words to fit template

How much of this is not understanding?

•  Very li_le. •  A few adult sounds are confusable (f, ɵ) –  But not that many

•  Good at discrimina8ng contrasts of na8ve language –  (Later this week: weird counterevidence)

•  Even for weak stress, can hear syllables –  Gerken & McIntosh (1993)

•  Find was dog for me (confusion!) •  Find the dog for me (no confusion)

kon

You will be assimilated.

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