Chapter 3 Flashcards
What do studies show about auditory discrimination?
- infants start hearing sounds about about the 20th week of gestation
- 2-7 day olds localize rattling noises
- by 4 months, they can discriminate by localization, fundamental frequency, intensity, duration
- infants prefer human speech and mother’s voice to other sounds and voices
Speech perception 2-4 months of age
- seem to hear in categories - if obstruents change to continuants, the suck suck swallow pattern changes and/or they turn their head
- they hear plosives or stops better than fricatives
- can discriminate velars from alveolars
- can discriminate stress changes (intonation, prosody)
- can discriminate between /a, i, u/
- like ‘motherese’
- have difficulty with embedded stops in intervocalic position (might lead to WSD)
Speech Perception 5-12 months
- better discrimination ( /sa/ vs /za/ can be discriminated around 6-8m)
- Around 8 months can be taught to discriminate sounds of other languages (less able to do that at 12mos because they start forming bins of their own language)
Why is speech perception important to us when the child is under 12m?
If child isn’t making sounds by 12 months, we can find out if its a hearing problem
•Early Intervention
• more preemies being born with feeding, swallowing, hearing problems (speech overlaid function)
Questions to ask parents that might help us understand child’s auditory perceptions?
- Does your child stop crying when you talk to her?
- Does your child differentiate your voice from a sibling?
- When you stop talking, does she “fill in” the silence?
- does your child turn her head to loud sounds?
- does she react to your stress/different tones?
Why are Infant Sound Productions so limited?
- Short Vocal Tract
- Short Pharyngeal Cavity
- Anterior tongue placement
- High larynx
- Close approximation of velopharynx & epiglottis
- Begin to approximate adult shape at 6-8 mos.
Oller’s 5 Stages
- Phonation
- Coo and Goo
- Exploration/expansion
- Reduplicated Babbling
- Variegated Babbling
Oller Stage 1
Phonation Stage
• 0-1 month of age
• Reflexive vocalizations: crying, fussing, Coughing, sneezing, burping for attention, hunger
• Syllabic nasals, but with limited resonance
• Non-distress sounds
Oller Stage 2
Coo and Goo Stage • 2-3 months • Primitive sounds - irregular timing • Velar consonant-like sounds • A sound similar to rounded vowel /u/ • Tongue clicks at back
Oller Stage 3
Exploration/Expansion Stage
• 4-6months
• Better control of laryngeal pharynx & articulators
• Improved oral resonance of vowels (more adult like)
• Squeals, growls, raspberries, friction noises
• Vocal play stage
• Begin to see VC and CV—with “not great” constriction
Oller Stage 4
Reduplicated Babbling (Canonical)
• 7-9 months of age; no later than 10 mos.
• Better oral (& nasal) resonation: better controlled
• C1V1C1V1 (bababa) and C1V1C1V2 (bababo) , but not used with intent; i.e., reduplication
• stops, nasals, glides,/ɛ, ɪ, ʌ/
• Velar-like sounds decrease (babies are moving around more, spending less time on their backs)
• Bilabial and alveolar usage increases
• Unaided deaf children often don’t reach this stage by 1 year of age
Oller Stage 5
Variegated Babbling Stage
• 10-12 months
• Non-reduplicated babbling, i.e., consonants and vowels may change
• Intonation pattern matures
• Connected strings resemble jargon/adult speech
• Vowels are beginning to stabilize: /ɛ, i, ʊ, ʌ, ɪ, æ, ɑ/
• Babbling often continues into the First-Word stage
Longitudinal Studies
• Researchers follow a small # of children individually over a considerable amount of time
Cross Sectional Studies
- Study includes cross-section of children in the US by age, gender, culture, ses, city, iq.
- Yeilds average group data
- Attempts to determine “age of mastery”
Place aquisition
stops > nasals > fricatives
• stops more common because they can’t control the stream of air for nasals and fricatives; lack of control
