However, the child’s early phonetic inventory (table 1) suggests that the child has a basic contrastive system and indicates that their phonological system has commenced, which will see an increase in new words and the emergence of two-word utterances (Grunwell, 1981). m| n| p b| t d| w| | Table 1: A phonetic inventory of a child 1. 6-2. 0 years (Grunwell, 1981). Grunwell (1981) presents a ‘chronology of phonological processes’ (p175) which reflects a child’s phonological development in terms of the disappearance of simplifying processes between 2. 0-4. years. These processes are summarised in table 2 and show that reduplication and consonant harmony are the only structural simplification processes outgrown by age two, which agree with the findings of Vihman & Greenlee (1987). Structural simplification is generally typical of the earlier stage of phonological development (Vihman, 2004). However, phonological processes; final consonant deletion, cluster reduction, fronting, gliding and stopping are regularly used by children until nearly age three, with less consistent use thereafter (Vihman et al, 1986).
Vihman (2004) states that half of her three-year-old subjects used gliding and palatal fronting, but the substitution of inter-dental fricatives were regularly used by all subjects and are associated with the highest frequency of errors. Table 2 suggests that velar fronting in particular is the first systemic simplification to be outgrown, at 2. 6 years. Despite this, it shows that obstruents do not occur in a child’s inventory until age three, and that these must be mastered before obstruent and liquid clusters can be produced correctly (Vihman, 2004).
Vihman & Greenlee (1987) show that the specific phonetic tendencies found at age one seem to be unrelated to the phonological errors at age three and suggest that phonetic preferences change over time. Vihman (2004) suggests that children with an exploratory approach to phonological development explore a wide range of sounds at age one and were more likely to delete consonants at age three, whereas children with a systematic approach constrain their word selection patterns at age one and are less likely to use whole-word processes at age three (Vihman, 2004).
However, Vihman & Greenlee (1987) show that 73% of children’s utterances at age three were judged intelligible, which correlates with lower phonological error scores. In conclusion, individual differences are a significant in ones phonological system and problematic in generalising ‘normal’ developments. However, a three year old child will have overall relative phonological advance (Vihman & Greenlee, 1987) and the majority of simplifying phonological processes used at age one will no longer apply regularly (Vihman, 2004). References Grunwell, P. 1981) The development of Phonology: A Desciptive Profile. First Language. 2: 161-191 Ingram, D (1986) Ch10: Phonological Development: Production. In Fletcher, P & Garman, M. Language acquisition pp223-239 CUP: UK 2nd Edition Menn, L. & Vihman, M. M. (2011) Part V: Features in Phonological development: Features in Child Phonology: Inherent, Emergent, or Artefacts of Analysis? In Clements, N. G & Ridouane, R (Ed) Where do Phonological Features Come From? Cognitive, Physical and developmental bases of distinctive speech categories. John Benjamins Publishing Company. p259-303 Vihman, M. M (2004) Ch3: Later Phonological Development. In Bernthal, J. E & Bankson, N. W, Articulation and Phonological Disorders, pp105-138. Englewood Cliffs, NJ: Prentice Hall. 5th Edition. Vihman, M. M. , Ferguson, A. & Elbert, M (1986) Phonological development from babbling to speech: common tendencies and individual differences. Applied Pyscholinguistics, 7: 3-40 Vihman, M. M. & Greenlee, M. (1987) Individual Differences in Phonological Development: Ages one and three years Journal of speech and hearing research. 30: 503-521
