Study Question.• Compare and contrast acoustic and articulatory phonetics

04/20/23

• Language» Speech perception

◊ Acoustic Phonetics

◊ Articulatory Phonetics

◊ Top-down processes

Language

• Phonology: The rules underlying production and comprehension of speech.

• Phonetics: The nature of linguistic sounds.» Articulatory phonetics: Placement of the mouth, tongue, lips,

etc. used to produce particular sounds.

» Acoustic phonetics: Physical characteristics of speech sounds.

◊ The Speech Spectrograph

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• Some Basics» Qualitative and quantitive elements of sensory stimuli

Low

High

Com

pres

sion

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• The Speech spectrograph

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• Acoustic Phonetics» Phoneme: The smallest unit of speech that if changed

would change the meaning of a word.E.g., “Pit” ----> /p/ + /I/ + /t/

/b/

/b/+/I/+/t/ = “bit” /p/+/i/+/t/ = “peat”

/i/

/b/+/I/+/g/ = “pig”

/g/

LanguageConsonants Vowels

p pull s sip i heedb bull z zip I hidmman r rip e baitw willf fill æ badv vet u boot thigh U put

y yipt tie k kale o boatd die g galen near h hail a hotl lear sing

shoulds head

pleasurez

c chopgyroj

thyo but

V

bought

c

sofa

e

manyi

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• Articulatory Phonetics» Three ways in which consonants differ.

1. Place of articulation– Bilabial --> /p/

– Labiodental --> /f/

– Dental --> //

– Alveolar --> /z/

– Palatal --> /ˆz/

– Velar --> /k/

– Glottal --> /h/

Language

• Articulatory Phonetics» Three ways in which consonants differ.

2. Manner of articulation– Stops --> /b/

– Fricatives --> /s/

– Africatives --> /j/

– Nasals --> /m/

– Lateral --> /L/

– Semivowels --> /r/

3. Voicing

◊ Vibration of vocal chords

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• Articulatory Phonetics» Voicing

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• Articulatory Phonetics» Is speech special?

◊ Specialized neural mechanisms for perceiving speech. – Categorical perception

Voice onset-time and distinguishing /d/ from /t/

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• Articulatory Phonetics

» Vowels◊ Positioning and part of tongue

– Height

High (/i/ beet)

Med (/e/ bait)

Low (/a/ pot)

– Part

Front (/I/ bit)

Central (but)

Back (/o/ boat)

Language

• The search for invariants

» Distinctive features◊ Chomskey & Halle (1968)

– The Sound Pattern of English

5 groups of features

◊ Miller & Nicely◊ Articulatory features

» Problems with a simple bottom-up approach◊ There are no periods of silence between phonemes

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• The search for invariants» Phonemic information is presented in parallel

◊ Coarticulation◊ E.g. Cf. /M/ in “Tim” vs. “/M/ in “mad”

» We perceive them as the same, but they are different

» We perceive the same sound differently according to the context

◊ E.g.: Writer vs. Rider

◊ E.g.: Insert a silence between /s/ and /i/ --> “ski”

Insert a silence between /s/ and /u/ --> “spew”

Language

• Top down processes» Phonemic restoration effect (Warren, 1970)

◊ Their respective legi*latures◊ Found a *eel on the axle◊ Found a *eel on the shoe

Language

• Perceiving conversational speech» Two main problems:

1. There are no physical boundaries between words– Anna Mary candy lights since imp pulp lay thing

2. Speech is sloppy– -> Misheard Lyrics

– -> This was the best buy vs. She is a bad girl

Language

• Perceiving conversational speech» Two main problems:

QuickTime™ and aDV/DVCPRO - NTSC decompressor

are needed to see this picture.

Language

What are you doing ?

Language

Whad’ya doin’?

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• Top-down processes and speech perception

» Phonemic perception◊ The McGurk Effect

» Sentence comprenension◊ Miller & Isard (1963)

– Participants shadow sentences:

Grammatic: Bears steal honey from the hive.

Semantically incorrect: Bears shoot honey on the highways.

Ungrammatic: Across bears eyes honey the bill.

Language

• Top-down processes and speech perception◊ Miller & Isard (1963)

– Results

Gram. Nonsem.Nongram.

No noise 89% 79% 56%

Mod. Noise 63% 22% 3%