speech perception Flashcards
challenges of speech perception
- no clear gaps between words
- co-articulation: acoustic realisation on speech depends on what you’ve just said and what you are about to say > the same words can come out differently each time
also pronunciation varies from speaker to speaker, accents, etc
how do we produce speech
- lungs push air up the trachea
- which vibrate the vocal cords in the larynx
- sounds from the vocal cords are then shaped by the supraryngeal vocal tract
labial consonants
lips used/touch
alveolar consonants
tongue touches behind teeth
velar consonants
tongue toches back of mount
stop
air flow stops completely
voice
when you say them vocal cords vibrate
unvoiced
no vibration
fricative
constriction does not happen completely, friction involved
nasal
airflow redirected to nasal cavity
sound waves
- periodic displacement of air molecules, creating increases and decreases in air pressure
- when we plot changes of sound pressure over time
- molecules come closer or further apart - inc and decr pressure
–> forming waveforms
spectograms
split sound into different frequencies at each moment
amplitude: indicated by colour
- splits info into different frequency channels - depicts info that the brain gets
source and filter theory
source: the vibrations of the vocal cords
filter: superlaryngeal vocal tract structure that shapes the sound produced by the source
source only
can maybe interpret whether sound is a question? or a statement.
the gender, happy or sad
source AND filter
- intelligible speech
- filter (supralaryngeal vocal tract, lips, teeth) important for sounds - PHONEMES
- filtering appears as band of energy at certain frequencies in spectrograms Called FORMANTS
lowest three formants
F1 F2 F3
these are important cues for identifying vowels
- brain can know which vowel it is hearing by detecting these auditory CUES
formants for vowels
F1 F2 F3
formants for consonants
F2 F3