Chapter 3 Flashcards
Frequency
Number of wavelengths that pass a given point in a given amount of time
(Pitch)
Amplitude
Amount of change a wave undergoes in one cycle
Fundamental frequency
Lowest frequency produced by vibrating object
Overtones
Higher frequencies produced by vibrating object
Timbre
The psychological perception of sound wave complexity
Periodic sound (Vowels)
- Regularly repeating pattern
- Produced by vibrating object
- Perceived as ringing or musical
Aperiodic sound (Consonants)
- No regularly repeating pattern
- Produced by collisions or friction
- Perceived as noise
Cochlea (“concha”)
Organ of auditory sensation (inner ear)
Basilar membrane
Extends inside cochlea, undulated in vibrating fluid of cochlea
Hair cells
Specialized cells of basilar membrane, sensitive to difference frequencies
Tonotopic organization
Progressive arrangement of cells sensitive to different frequencies
Primary auditory cortex (A1)
Superior temporal lobe, initial processing of input from cochlea
Coarticulation
- Overlapping phonemes in the speech stream
- Preceding or following consonant modifies vowel formants
Plosives
b & p, d & t, g & k
Aspiration
Puff of air accompanying the release of some plosives
Voice onset time (VOT)
Difference between release of plosive (consonant) and beginning of vocal fold vibration (vowel)
Categorical perception
Continuously changing stimuli perceived as belonging to discrete sets
Phonemic restorarion
Filling in missing segments of speech stream with contextually appropriate material
Multimodal perception
Senses strongly interact to produce rich experience of world
McGurk effect
Speech perception combines both auditory and visual information
High-amplitude sucking technique
- Measures frequency of sucking on non-nutritive nipple
- Changes in frequency indicate discrimination of stimuli
Newborns prefer
- Mother’s voice
- Mother’s language (spoken by another woman)
- Familiar nursery rhyme (heard in the womb)
Infant-directed speech (Motherese/caregiver speech)
Way of speaking to infants, attracting their attention, helping them learn language
Prefer infant-directed speech because
of its acoustic qualities and its features are clearer and more exaggerated
Prosodic bootstrapping
Infants use intonation and stress patterns to infer phrase and word boundaries
Most multisyllabic words in English begin on a
stressed syllable
Metrical segmentation strategy
rule of thumb assuming English words begin on a stressed syllable
Transitional probability
The likelihood that a particular event will occur next given the current event
Perceptual narrowing
Process of transitioning from more universal or unconstrained perceptual abilities to those that are more narrow or constrained
Distributional learning
Tracking of the frequency and location of various sounds in the speech stream
Lack of invariance
No reliable relationship between phoneme and acoustic signal
Motor theory
People perceive speech by inferring articulatory gestures, not analyzing the speech stream
Nativism
View that behavior is mainly shaped by natural selection, encoded in genes
Language acquisition device (Chomsky, 1959)
- Specialized processing units in the brain
- Guide rapid development of language in infants
Module (Fodor, 1983)
Dedicated neural system evolved to perform a specific function
Speech is special (Liberman, 1982, 1996)
View of speech perception as distinct from general auditory perception
Reasons for this idea:
- Speech perception and production are uniquely human abilities
- Processed via the motor system
- Objects of speech perception were the intended vocal tract gestures
General auditory framework
Speech perception operates by same mechanisms that have evolved for perceiving environmental sounds
Fuzzy-logical model of perception
Perceptual decisions made by matching relative goodness of sensory inputs to prototypes in memory
Direct realism
- Newer form of motor theory
- Sensory input sufficiently rich, allows us to completely recover object of perception
- Rejects “speech is special”
Mirror neurons
- Neurons in primates that fire when perceiving or performing task
- Links perceptual and motor systems
