Infant Speech Perception

Question 1

Describe infant speech perception from birth through 6 months.

Answer 1

• Fetuses demonstrate consistent response to auditory stimulation by 25-29 weeks (gestational age)
• Full-term newborns have over 2 months auditory experience
• Neonates found to respond differently to native vs. non-native variants of vowels (can access frequencies up to 2600 Hz in-utero)

Question 2

What is some evidence for newborn/fetus perception of suprasegmental information?

Answer 2

• Have the ability to discriminate native language from a foreign language
• Have the ability to discriminate mother’s voice from that of another woman
• Those exposed to a particular nursery rhyme in-utero showed preference for it over other nursery rhymes after birth

Question 3

What is some evidence for infant categorical perception?

Answer 3

• Studies have shown that infants may have some initial auditory sensitivity to particular acoustic-phonetic cues, but they are not rigid and can be influenced by linguistic input
• Many consonant contrasts are perceived categorically but vowels are perceived more continuously

Question 4

What is some evidence for infant perception of segmental information?

Answer 4

• Acoustic properties of speech that differentiate phonemes
• Young infants demonstrate sensitivities to fine-grained changes in segmental info despite lack of experience with high frequencies (due to filtering in-utero)

Question 5

What is some evidence for infant sensitivity to phoneme inventory?

Answer 5

• Studies have shown that young infants can discriminate segmental properties after little to no experience with language
• Familiarity with native segmental characteristics emerges later than familiar with suprasegmental characteristics
  
  • Infants demonstrated longer looking times for their native rhythm but not their native phoneme inventory

Question 6

Describe the effects of language experience on speech discrimination.

Answer 6

• Younger infants can discriminate phonemic contrasts that are difficult for adults (e.g. English /d/ vs. Hindi /d/) but 10-12 month olds could only discriminate contrasts that were linguistically-relevant to their native langauge
  
  • Suggests that consonant discrimination is affected by language input
• Similar results have been shown between vowel contrasts as well

Question 7

What is the universalist view of infant speech discrimination?

Answer 7

• Infants are born able to discriminate any phonemic contrast that could potentially be relevant to any of the world’s languages
• Then, with experience, infants lose the ability to discriminate contrasts that are not relevant for their language

Question 8

What are limitations of the universalist view of infant speech discrimination?

Answer 8

• Doesn’t take into account subphonemic information that is relevant for other aspects of speech perception/language acquisition (i.e. allophones)
• Some contrasts require language experience before they can be discriminated (i.e. Spanish VOT contrasts)
• Discrimination of some language contrasts improve with language experience

Question 9

What are the 3 mechanisms of learning in infants?

Answer 9

• Recognition memory
• Associative learning
• Statistical learning

Question 10

What is recognition memory?

Answer 10

• To recognize something, it must be encoded in memory
• Has been studied more in the visual than auditory domain
• Recognition memory improves significantly during 1st year of life and correlates with language/cognitive outcomes
• EX: infant preferences for mother’s voice & native language
• Work with older infants suggests that infants’ representations of speech sounds become more generalizable with experience and development (i.e. better recognition of talkers of the opposite sex)

Question 11

What is associative learning?

Answer 11

• Word learning is a sophisticated type of associative learning
• In infancy, associative learning takes place in nonlinguistic domains prior to 1st words (i.e. object parts, motion trajectories)
• In the auditory domain, young infants can learn simple associations (i.e. vocal affect, facial expressions)
• Older infants associate complex strings of speech with objects, actions, attributes, & experiences (important for language acquisition)

Question 12

What is statistical learning?

Answer 12

• Involves learning the probability of Y given X
• Infants are sensitive to the statistical properties of speech sounds in their language
• Infants show a novelty preference for sequences with lower probability
• Allows for infants to learn abut how phonetic segments are distributed/organized in the ambient language during the 1st year of life

Question 13

In addition to speech perception capacities and learning mechanisms, what also plays a role in language acquisition?

Answer 13

• Motivation

- Intention