Speech production involves
-Respiration
-Phonation
-Articulation
Vowels
Vibration of the vocal cords and changes in the shape of the vocal tract by moving the articulators
Formants
The phonetic quality of a vowel
First and second formants
The 1st has the lowest frequency and the 2nd has the next highest
Formant Transitions
Rapid changes in frequency before or after consonants
Consonants
Produced by a constriction of the vocal tract
Phonem
Smallest unit of speech that changes the meaning of the word
-47 phonemes
-13 vowel sounds
-24 consonant sounds
Grapheme
Letters that spell a sound (c k -ck ch)
Morpheme
Smallest meaningful word part
Coarticulation
Overlap between articulation of near by phonemes also causes variation (toys sounds like toyz)
Variability from different speakers
-Speakers differ in pitch, accent, speaking speed, and pronunciation
-Familiar words
People perceive speech easily despite the….?
Variability problems due to perceptual constancy
Categorical Perception 1
-Cues result in the perception of a limited number of sound categories
VOT-Categorical Perception 1 Example
Time delay between when a sound starts and when voicing begins
-da (17) and ta (91)
Categorical Perception 2
-Long and short VOT stimuli
-No incremental changes, sudden da to ta change
McGurk Effect
Hear one thing, see another
-Visual stimulus shows ga-ga
-Auditory Stimulus shows ba-ba
-Both is da-da
-Eyes closed is ba-ba
Word Superiority Effect
Recognize words faster than non words with word rules
Phoneme Restoration Effect
You filter the stimuli and your brain filled in the blank of what it should be
Perceiving Words in sentences 1 of 2
-Normal grammatical sentences
-Anomalous sentences that were grammatical
-Ungrammatical strings of words
They had to repeat the sentences as they heard them
Perceiving Words in sentences Results
-89% accurate w normal sentences
-79% accurate for anomalous sentences
-56% accurate for ungrammatical word strings
*larger differences w background noise
Speech Segmentation
The slicing of continuous speech (know where breaks go)
-Phoneme identification
Broca’s Area
-Left frontal lobe
-language production and articulation
-Take your thoughts –> speak and write w/ motor functions
Wernicke’s Area
-Left temporal lobe
-Language comprehension and processing
Broca’s Aphasia
-Expressive aphasia
-Awareness
-Understand speech, can’t form sentences
-Hard for patient