early communication

Preverbal 0-12 months, 3 key words

3-8 months: Canonical babbling: “bababa”

8-12 months: Variegated babble: varying consonant and vowel syllable to syllable

8-12 months: Jargon: increased use of intonation, rhythm in babbling

Preverbal 0-12 months, milestones (roughly consider in 3 stages)

Birth: 3 months reflexic, coo & goo

3-8 months: canonical babble

8-12 months complex babble

preverbal 0-12 months, important characteristics

comprehension within rich context and routines

intentional communication approx. 8-12 months

preverbal 0-12 months, formation of phonetic categories

hear many occurrences of sounds, encode essential features (vowels scatterplot from research paper)

preverbal 0-12 months, biological vs. learning theory

discontinuity vs continuity in babbling & speech

single word 12-24 months, 3 key words

protowords: invented words during transition from preverbal to speech

over-extension: meaning for word too broad (doggy → dog, cat, pig, cow)

Under-extension: word category too narrow (only dads red truck is “truck”)

single word 12-24 months, milestones

first words around 12 months

18 months: 50 words (lots of nounds and perceptual salience)

18-24 months: vocabular spurt

single word 12-24 months, important characteristics

first words mostly nouns

child understands more than they can express

single word 12-24 months, have acquired what

many vowels, toward the end → two-word utterances occur

Expansion 24-36 months, key words (MLU)

Mean Length of Utterance (MLU) = total # morphemes / # utterances (usually calculated for average length of a sample of 50 to 100 utterances)

Expansion 24-36 months, milestones

acquire most vowels by 3 years old (around 600 words)

acquire early consonants nasals, glides, bilabials

beginning multi-word stage

Expansion 24-36 months, important characteristics

typical two-word utterances

agent + action

action + object

agent + object

action + location

Expansion 24-36 months, other comments

appear (to adults) that they understand a lot (than they actually do)

world knowledge facilitates comprehension

vocabulary still more nouns than others, but start building

Elaboration 36-60 months, key words (overgeneralization)

overgeneralization: errors in stretching grammatical rules

runned vs ran

swimmed vs swam

Elaboration 36-60 months, milestones

multi-word stage, longer utterances (agent+action+object)

continue to master → grammatical morphology, syntactic rules, different sentence types, later consonants and clusters

Elaboration 36-60 months, important characteristics

beginning of more complex linguistic concepts (48-60 months)

passive, figurative language, metalinguistic skills

Elaboration 36-609 months, additional comments

most stops acquired by 4 years of age, the rest are among the latest acquired speech sounds (continue to develop beyond age 5)