1. Vagetative: Sounds of discomfort or reflexive actions - Crying, oughing, burping, sucking: 0-4 months
2. Cooing: Comfort sounds, vocal play - Grunts and sighs become vowel-like 'coo's. Laughter starts. Hard consonants and vowels are produced. Pitch (squeals and growls) and loudness (yells) practiced: 4-7 months
3. Babbling: Extended sounds resembling syllable-like sequences. Repeated patterns - Sounds linking to own langauge. Reduplicated sounds ('ba-ba') and non-reduplicated (variegated) such as 'agu': 6-12 months
4. Word-like vocalisations: 9-12 months
Lexical and Grammatical Stages of Development
1. Holophrastic/one word: One word utterances - 12-18 months
2. Two-word: Two-word combinations - 18-24 months
3. Telegraphic: Three and more words combined - 24-36 months
4. Post-Telegraphic: More grammatically complex combinations - 36+ months
Early Phonological Errors
Deletion: Omitting the final consonant in words e.g. do(g), cu(p)
Substituion: Substituting one sound for another (especially the 'harder' sounds that develop later e.g. 'pip' instead of 'ship'
Addition: Adding extra vowel sounds to the ends of words, creating a CVCV pattern e.g. 'doggie'
Assimilation: Changing one consonant or vowel for another (as in the early plosive sounds for 'd' and 'b') e.g. 'gog' instead of 'dog'
Reduplication: Repeating a whole syllable e.g. 'dada', 'mama'
Consonant cluster reductions: Consonant clusters can be difficult to articulate, so children reduce them to smaller units e.g. 'pider' for 'spider'
Deletion of unstressed syllables: Omitting the opening syllable in polysyllabic words e.g. 'nan' for 'banana'
Rate of Lexical Development - Number of Words by A
- 12 months old - 50 words
- 24 months old - 200 words
- 36 months old - 2,000 words
Types of Overextension
- Catergorical Overextension: The name for one member of a category is extended to all members of the category. E.g. Apple used for all round fruit. 60% of overextesnions
- Analogical Overextension: A word for one object is extended to one in a different cateogry; usually on the basis that it has some physical or functional connection. E.g. Ball used for round fruit. 15% of overextesions.
- Mismatch statements : One-word sentences that appear quite abstract; child makes a statement about one object in relation to another. E.g. saying 'duck' when looking at an empty pond. 25% of overextensions.