Speech Perception Test 1

Preferences

Present stimuli & record behavioural consequences ( duration of natural behaviours)

Conditioning

Train infant behaviours in response to stimuli

Habituation experiment

Present stimuli until baby is habituated then present new stimuli & see if they have been dishabituated

Sine -wave speech

Stripping details of speech down, keeping only key/ strongest frequencies

Speech preference @birth

Preference for species-specific vocalizations in other species

Vouloumanos & werker 2007 found

Newborns show equal preference for human speech & rhesus monkey calls over sine-wave speech. By 3 months show preference for human

Recognition before birth

Recognize the rhythm & melody of mothers voice;

Cat in the hat study found

Babies showed preference for the story heard in the womb even when read by a strangers voice

Low-pass filtered

Lets in low frequency waves only, while filtering out the high. Inside of womb

Mahler et al 1988 proved

Newborns can discriminate between their native language & another if they belong to a different rhythm group

What do infants use to discriminate language

Since they can tell apart differences in low-pass filtered sounds this suggests tug use prosidy

Rhythmic classes

Languages in same cluster share rhythmic structure, able to discriminate languages if they are in a different class

Infant directed speech

Special register used when speaking to babies, characterized by higher pitch contour, slower tempo, repetition, more extreme vowels

Infants prefer IDS

In non-native "with-in “ languages, in sign &hearing @months show greater affection & emotion for IDS sign

IDsign

Parents prioritize positive affect over grammar

@4 months prefer IDs

Preference is for pitch changes & positive affect emotion

Key aspect of perceiving speech sounds

Treating sounds from same phoneme category as being the same (diff versions ofp) and from different category as being different (pvsb). Goal to tell them apart and group together properly

Categorical Perception

Perceiving everything on one side of the boundary as being the same, items on the other side as being different even though amount of acoustical difference is equal between each sound (10ms)

Voice onset time VOT

Period of time from when the lips open & the vocal chords begin to vibrate

Process initial ability

To discriminate speech sounds along dimensions important for language. starting out as universal listeners treating sounds as categories

Over the 1st year worsening

Ability to discriminate sounds that are not different phonemes in heir native language : consonants, vowels, tones.

Over the 1st year improved

Ability to discriminate sounds that are different phonemes in their native language

Worker & tees longitudinal discrimination

6 month old started out equally @telling apart hind/salish but got worse by end of 1st year because of different categories not matching their language