Psycholinguistics : Speech perception

Question 1

Speech perception ?

Answer 1

Mapping of auditory input speech to stored linguistic representations

Question 2

2 major properties ?

Answer 2

High acoustic variability + multimodal cues

Question 3

Variability ? (3)

Answer 3

Btw talkers : Regional accent, gender, age, social status

Within talkers : co-articulation, dialog Noise in speech

Question 4

Multimodal cues

Answer 4

lip, head, face, jaw mouvements

Question 5

BOLD ?

Answer 5

Blood Oxygen Level Dependent

Question 6

Basal ganglia

Answer 6

Motor control + motivation + prediction

Question 7

Cerebellum

Answer 7

Time perception - Timing

Question 8

Which network for prediction ?

Answer 8

Subcortical - cortical for temporal processing and predictions in speech perception

Question 9

Neural dissociation in processing noise and accent in spoken language comprehension.

Answer 9

Adank P, Davis MH, Hagoort P. 2012
The brain doesn’t do the same thing when dealing with noise or unfamiliar accent distortion
Ventral + Dorsal : noise
Ventral only : unfamiliar accent

Question 10

Why only ventral for unfamiliar accent processing ?

Answer 10

Only areas relative to phonological processes, coz the system tries to adapt, learn new representations

Question 11

Non native phonemic contrast

Answer 11

Ability to perceive speech sounds greatly depends on the inventory of phonemes of the native language acquired during first months of life (Japanese don’t make a difference btw “r” and “l”)

Question 12

Adank 2012
Méthodo

Answer 12

fMRI STUDY (BOLD)

Participants
26 monolingual dutch speakers
right-handed
homogenous sample

Stimuli
204 sent. in dutch
204 sent. in unfamilliar accent
204 sent. sent with noise

Task
Sentence true or false (button box)

Behavioral measures
From the offset of the sound file

Question 13

Adank 2012
Results

Answer 13

Behavioral results
Response time : more difficult for nosie & accent (no signf diff)
The two distortions were matched for the difficulty of processing

BOLD signal results
Increased activation in bilateral inferior frontal area (IFG and FO) for NOISE vs CLEAR
Increased activation in left temporal cortex (STG and STS) for ACCENT vs CLEAR

Question 14

Adank 2012
Interpretation

Answer 14

The dual streams model assumes that left frontal areas are more engaged inadverse speech conditions
→ Data not totally in favor with the dual stream model

External distortion (noise)
Recruitment of cortical areas involved in higher order processing (semantics, syntax) of spoken language

Speaker-related distortion
(phonetic and phonological variation)
Recruitment of cortical areas involved in auditory and phonological processing

Question 15

Answer 15

Question 16

Perceptual distance

Answer 16

Goslin et al 2012

ERP : home, regional, foreign accent
(time locked final word)

• P : native monolingual English, right-handed
• S : sentences recorded in home accent, regional accent and foreign accent
• T : press button with their dominant handwhen the final word was the name of an animal.

Activation (200ms)
hyp : foreign>regional>home
res : regional > home > foreign
hypothese de distance perceptuelle non confirmée

Regional accent
greater responses only at early stage suggests a quick adaptation at prelexical level

Foreign accent
lower responses at early and late stages suggest a reduction of prelexical and lexical activation

Question 17

Hanulikova 2012

Brain correlates of on-line in speech perception

(text - method)

Answer 17

Hanulikova et al 2012
ERP
“Expectation is different when a non-native accent is perveived”

Participants
17 Dutch speakers

Stimuli
grammatical incorrect sentences with either gender disagreement btw the definite determiner and the noun, or inflective adjectives

Task
Answer comprehension questions

Semantic manipulation is a good control to check if the effect is related to the knowledge of the world and not a specific gramatical process (same level of comprehenson to check)

Question 18

Hanulikova - Results

Answer 18

• Speaker adaptation can lead to be not sensitive to grammatical errors
• These adjustments differed as a function of the accent of the speaker
• Listeners adjust their probability model following the speaker’s characteristics during spoken language comprehension
• Probability modal means brain predictions about language

We can totally adapt when the mistake is predictable, and focus on comprehension

Question 19

Prediction

Answer 19

Ability to generate predictions of forthcoming events based on prior knowledge ad experience about the world is a result of evolutionnary pressure for survival

KEY ROLE OF PREDICTION

Pickering & Garrod 2007
Tip of the tongue
Online lexical prediction driven by sentence context (written & spoken language)
Syntactic & semantic predictions
Prediction of the end of speaker’s turn
→ Subcortical-cortical network (involving basal ganglia-cerebellum)

Imitiation (repeat word, grammar, speech rate…)

Question 20

Lesage

Answer 20

2012 - rTMS study
Role of cerebellum in language predictions
from speech inputs

Finish the sentence by looking at a drawing on the screen

Result
more time to choose the object when cerebellum stimulated
= No prediction

→ Cerebellum involved but not alone

Question 21

Multimodal cues of speech

Answer 21

Relevance of natural head motion in speech perception

Impact of visual prosody
Munhall 2004