Speech Perception and Speech Theories

- phonetics: motor aspect; use brackets [ ]

- ex: [ b ]

- phonemics: deals with role of sound in culture/phonology; use slanted lines / /

- ex: ball /IPA form of b a l/

- speech perception: means by which acoustic, visual, or tactile signals are mapped onto the language forms (syntax, morphology, etc.)

# Speech Perception

## Infants

- perception begins as soon as hearing begins

- discriminate at phoneme level

- phonemes have no meaning but are important in devt of speech

- beginning to become sensitive to a variety of higher level linguistic structures

- 0-5 is the "sponge era"; crucial part of language devt

## Speech Acoustics

- acoustic properties of speech, such as intonation, intensity and speaking rate

- aka suprasegmentals

- spectrogram: represents graphically frequency over a specific time interval

### vowel characteristics

- tongue height

- mouth/tongue openness

- lip rounding

- tenseness

## characteristics of consonants

u know this

- manner

- placement

- voicing

# Theories of Speech Perception

## Issues

- Linearity: stresses link between specific sound with corresponding phoneme

- Segmentation: speech signal is divided into discrete units

- Speaker Normalization: we are able to understand sounds pronounced differently by different people, regardless of accent, age, sex, pitch

- Basic unit of perception: how do we perceive sound? words, syllables, phonemes, allophones #searchuplater , etc.?

## Categories

- Active: stresses link between perception and production

- Passive: sensory aspects of speech perception

- Bottom up: acoustic signal contains all info needed for recognition of sound (hearing the word, then adding meaning)

- Top down: higher level linguistic/cognitive operations (we perceive linguistic information, then auditory)

- Autonomous: signal is processed serially (step by step)

- Interactive: analyze acoustic signal as a whole

## Theories

- Motor theory: links speech perception and production

- can identify because can produce that sound

- Acoustic Invariance Theory: each phoneme has its own features

- ex: /p/ sound can be seen because lips are being used and plosive is heard

- Direct Realism: Interactive theory; perceive the signal as a whole, whether it be a phoneme or a word

- TRACE model: both top down and bottom up; analyzes acoustic and linguistic info at the same time

- Logogen theory: Interactive theory; provides meaning and context to a word once its heard

- ex: hearing dog gives you the picture of dog, plus you know how to say dog

- Cohort Theory:

- Autonomous stage: start of the word gives a list of all possible

- ex: "a___" could be apple, alike, amaze

- Interactive stage: eliminates all improper words in context

- Fuzzy logical model of perception theory

- fuzzy: is there a sound or not (0 no sound .5 ambiguous 1 present sound)

- prototype: compares sound heard to database of phonemes in ones mind

- Pattern classification: determines the best match between heard sound and

- Native Language Magnet theory

- "magnet" because we pull most familiar

- sounds in our database

- begins in early infancy

- first 10 months

- able to discriminate

- 10-11 months

- phonemes are prioritized based on what is frequently heard in child's language

# Acoustics Model of Speech Production

## Acoustic theory of vowel production (source filter theory)

- Source

- voice is made in larynx

- Filter

- Vocal tract acts as filter

- 3 Elements

- glottal sound

- vocal tract resonator

- sound at the lips

- Conditions

- source:

- vibrator

- transmitting medium

## Larynx

- control flow of air

- protection

- swallowing

- abdominal fixation

### periods

- quasi periodic signal: has a periodic pattern, but has variations in period and amplitude

### vocal tracts

- cavities act as natural resonators

- some cavities have anti resonant properties

## Acoustic Characteristics

- physical characteristics: ya need PRAAT ma boi

- perceptual characteristics: what we hear

| Physical | Perceptual |

| ---------------- | ------------------------------ |

| frequency | pitch |

| intensithy | loudness |

| spectrum | quality |

| duration or rate | perception of duration or rate |

## Fundamental frequencies

- number of oscillations per second

- called "F0"

- lowest frequency produced by a system

### formants

- used to differentiate vowels

- F1:

- determined by the volume of pharyngeal cavity

- associated with tongue height

- inverse relationship

- F2

- length of oral cavity

- associated with tongue advancement

- direct relationship

- Roundedness

- rounded has lower f2

- unrounded has higher f2

# Spectrogram

- PRAAT ma boii

- no specific numbers, but there's a range

- Periodic V Aperiodic

- periodic: there's a pattern

- aperiodic: no pattern

- consonants are aoeriodic

- vowels are periodic

- diphthong: transition between 2 vowels

## Consonants

- MANNER

- voice bar if voiced consonant

- Stop

- there's a big gap in between

- Fricative

- turbulent look;

- Affricative

- combo of stop and fricative

- "ch" #searchuplater

- nasals

- looks like a vowel a bit

- more faded vowel

- #thoughts i think it needs a vowel to compare to so you can know if its more faded than the vowel

- Approximants

- brining articuators together without friction

- "semivowels"

- there's a dip

- Trills

- lots of gaps; easy to remember

- PLACEMENT

- VOICING

# Segmentals and Suprasegmentals

## Suprasegmentals

- Stress: pointer for emphasis

- Intonation: rise and fall of pitch

- Duration: "ice vs eyes"

- Pausing

# Distinctive features

## Vowels

- sonorant sounds: spontaneous voicing

- consonantal sounds: closed vocal tract

- vocalic sounds: open vocal tract

## Consonants

- consonantal sounds

- vocalic sounds

- sonorant

- continuant: complete blockage of tract during production

- strident: fricative and affricatives; generate intense noise (basically annoying sounds)

- ex: /s/ /z/

- stop

- closure: with a stop gap

- voiceless: stop gap is silent

- voiced: stop gap has low freq band of energy

- release: burst of sound

- transition: moving toward production of another sound

- nasal

- nasal murmur: acoustic segment associated with nasal radiation of sound energy

- murmur has spectrum dominated by low frequencies with a prominence around 250Hz

- fricatives

- aperiodic sound waves

- #thoughts wow maybe i should participate in class to keep my awake

- affricatives

- approximants

- glides: vowel like

- w is similar to u. f3 and f4 are weak due to oral closure

- liquids

- differences in tongue tip (coronal) config are reflected in f2 but most obviously in f3

- glottal

- airflow is turbulent

- glottis wide open