Lecture 6: Language Development Flashcards
what age of infants does the high amplitude sucking procedure test?
infants from birth to 4 months of age
what does the high amplitude sucking procedure rely on?
infants’ sucking reflex
high amplitude sucking procedure
Infants hear a sound stimulus every time they produce a strong/high-amplitude suck on a pacifier
how does the high amplitude sucking procedure determine infants’ interest?
The number of strong sucks is an indicator of the infants’ interest
what do more strong sucks on the high amplitude sucking procedure represent?
more interest
two variations of the high amplitue sucking procedure
discrimination & preference
function of the discrimination high amplitude sucking procedure
Used to test whether infants can tell the difference between two auditory stimuli
the discrimination high amplitude sucking procedure is a variation of _____
the visual habituation paradigm
habituation phase of the discrimination high amplitude sucking procedure
each time an infant produces a strong suck, a sound is played. This continues until sucking has declined significantly (by about 20%)
test phase of the discrimination high amplitude sucking procedure
they hear a new speech stimulus every time they produce a strong suck
interpreting results of the discrimination high amplitude sucking procedure
If infants can distinguish between stimuli, sucking behaviour should increase
function of the preference high amplitude sucking procedure
Used to test infants’ preference for different stimuli
preference high amplitude sucking procedure method
2 different stimuli are played on alternating minutes each time a strong suck is produced. The number of strong sucks produced during the presentation of each stimulus type is compared
interpreting preference in the preference high amplitude sucking procedure
infants prefer a stimulus if they suck more during one stimulus minute type than the other
what has the high amplitude sucking paradigm shown about newborns?
- Prefer to listen to speech sounds over artificial sounds
- Prefer to listen to their mother’s voice over another woman’s voice
- Prefer to listen to their native language over another language
what does research using the high amplitude sucking procedure reveal?
that language learning starts in utero
what does speech perception rely on?
perceiving differences between speech sounds
what often distinguishes similar speech sounds?
voice onset time
voice onset time
the length of time between when air passes through the lips and when the vocal cords start to vibrate
categorical perception
we perceive speech sounds as distinct categories even though the differences between speech sounds are gradual
why is categorical perception useful?
because it focuses listeners on sounds that are linguistically meaningful while ignoring meaningless differences
infants’ categorical perception of speech study question
do infants perceive the same speech categories as adults?
infants’ categorical perception of speech study sample
1-month-old infants learning English
infants’ categorical perception of speech study method
used a high amplitude sucking paradigm to test the discrimination between /ba/ and /pa/
infants’ categorical perception of speech study conditions
- Different speech sounds: infants were habituated to /ba/ (20 ms VOT) and then tested with /pa/ (40 ms VOT)
- Same speech sounds: infants were habituated to 60 ms VOT /pa/ and then tested with /pa/ (80 ms VOT)
infants’ categorical perception of speech study findings
- Different speech sounds condition: found increased sucking when sound from new category (/pa)
- Same speech sounds condition: found no change in sucking when sound from the same category (/pa)
infants’ categorical perception of speech study takeaway
newborns have the same categorical perception of speech as adults
distinguishing speech sounds in adults vs. infants
Infants make more distinctions between speech sounds than adults
perceiving unimportant speech sounds in adults
Adults have difficulty perceiving differences between speech sounds that are not important in their native language
infants cross-language speech perception study sample
tested 6-month-old American infants learning English
infants cross-language speech perception study method
used the high amplitude sucking paradigm to see if they can discriminate between Hindi /Ta/ and /ta/
infants cross-language speech perception study results
after habituating to one of these Hindi speech sounds, they increased sucking when they heard other speech sounds
implications of infant cross-language speech perception
- Infants discriminate between speech sounds they have never heard before (i.e. speech sounds not found in their native language)
- Infants are biologically ready to learn any of the world’s languages
perceptual narrowing of speech perception
- Infants’ ability to discriminate between speech sounds they have never heard before diminishes around 8 months
- Infants lose the ability to discriminate non-native speech sounds at 10-12 months
- This improves their perception of speech sounds in their native language
word segmentation
discovering where words begin and end in fluent speech
when does word segmentation begin?
7 months of age
how do we pick up on patterns of words in our native language?
via statistical learning
examples of statistical learning in our native language
- stress-patterning
- distribution of speech sounds
stress patterning
Different languages place stress on different parts of a word
stress patterning in English
stress usually lands on the first syllable
stress patterning in French
stress usually lands on the last syllable
distribution of speech sounds
- Sounds that appear together often are likely to be words
- Sounds that don’t appear together often are more likely to be boundaries between words
preferential listening procedure
- There is a speaker on either side of an infant’s head
- When the infant looks at the speaker, a recording of speech plays
- There is different speech from each speaker
interpreting results of the preferential listening procedure
How long an infant spends looking in a particular direction/listening to a particular sound indicates how much they like it
familiarity effect in the preferential listening procedure
infants will listen longer to sounds they recognize
novelty effect in the preferential listening procedure
if first habituated to a sound, infants will listen longer to the new sound
distribution of speech sounds study method
preferential listening procedure with 8-month-olds
distribution of speech sounds habituation
- 8-month-olds listened to a stream of syllables for a long time (2 mins)
- Some syllables always occurred together
- Others rarely or never occurred together
distribution of speech sounds test
infants were presented with a syllable sequence that always co-occurred vs. syllable sequences that rarely co-occurred
distribution of speech sounds results
infants listened longer to the rarely occurring sequence
distribution of speech sounds takeaway
this shows that infants understood word boundaries by detecting the likelihood of syllables belonging together
cooing
Drawn out vowel sounds like “ooooooh”
when does cooing start
at around 2 months
benefits of cooing
- Helps infants gain motor control over their vocalizations
- Elicits reactions from caregivers leading to back-and-forth cooing with caregivers
babbling
Repetitive consonant vowel syllables like “papapa”
when does babbling start
at around 7 months
babbling across culture
- Speech sounds are not necessarily from the child’s native language
- Infant babbling is very similar across languages
babbling in deaf infants
Deaf infants that are exposed to ASL babble with repetitive hand movements made up of pieces of full ASL signs
what does babling in deaf infants provide evidence for?
that language exposure is critical for babbling
functions of babbling
social & learning function
social function of babbling
- practicing turn-taking in a dialogue
- Infant babbling elicits caregiver reactions which in turn elicit more babbling
learning function of babbling
- signals that the infant is listening and ready to learn
- Infants learn more when an adult labels a new object just after they babble vs. learning the word in the absence of babbling
when do infants appear to understand high-frequency words
around 6 months of age
understanding words before first words study method
shows 6-month-olds pictures of common items and monitor where they look when one of the pictures is named (eye-tracking)
understanding words before first words study findings
6-month-olds look at the correct picture more often than chance
understanding words before first words study takeaways
- Infants understand more words than they can produce
- Infants understand more words than their caregivers realize
first word
any specific utterance consistently used to refer to or express meaning
why are first words hard to identify?
- Babbling can sound like words
- The meaning of a first word can differ from its standard meaning
when are first words produced?
around 12 months
how are first words often pronounced?
in predictable ways
predictable ways first words are pronounced
- Omit difficult parts of words
- Substitute difficult sounds for easier sounds
- Reorder sounds to put easy sounds first