Phonological development in child
language acquisition
By/ Brwa R. Sharif
24/May/2013
Introduction:
Sound is at the beginning of language learning. Children have to learn to distinguish different sounds and to segment the speech stream they are exposed to into units - eventually meaningful units – in order to acquire words and sentences. Here is one reason that speech segmentation is challenging: When you read, there are spaces between the words. No such spaces occur between spoken words. So, if an infant hears the sound sequence “thisisacup,” it has to learn to segment this stream into the distinct units “this”, “is”, “a”, and “cup.” Once the child is able to extract the sequence “cup” from the speech stream it has to assign a meaning to this word. Furthermore, the child has to be able to distinguish the sequence “cup” from “cub” in order to learn that these are two distinct words with different meanings. Finally, the child has to learn to produce these words. The acquisition of native language phonology begins in the womb and isn’t completely adult-like until the teenage years. Perceptual abilities (such as being able to segment “thisisacup” into four individual word units) usually precede production and thus aid the development of speech production. (Phonological development, 2011)
1. Babbling
Despite obvious differences among the languages to which they are exposed, children from different linguistic communities exhibit significant similarities in their babbling. Such cross-linguistic similarities suggest that early babbling is at least partly independent of the particular language to which children are exposed. In fact, even deaf children babble, although their articulatory activity is somewhat less varied than that of hearing children. (O’Grady & Cho, 2001)
2. Developmental order
Babbling increases in frequency until the age of about twelve months, at which time it begins to give way to intelligible words. By the time children have acquired fifty words or so (usually by around eighteen months of age), they begin to adopt fairly regular patterns of pronunciation. Although there is a good deal of variation from child to child in terms of the order in which speech sounds are mastered in production and perception, the following general tendencies seem to exist.
■ As a group, vowels are generally acquired before consonants (by age three).
■ Stops tend to be acquired before other consonants.
■ In terms of place of articulation, labials are often acquired first, followed (with some variation) by alveolars, velars, and alveopalatals. Interdentals (such as [θ] and [ð]) are acquired last.
■ New phonemic contrasts manifest themselves first in word-initial position. Thus, the
/p/-/b/ contrast, for instance, is manifested in pairs such as pat-bat before mop-mob.
By age two, a typical English-speaking child has the inventory of consonant phonemes such as; stops /p, b, t, d, k, g, m, n/, fricatives /f, s/, and other /w/.
By age four, this inventory is considerably larger and typically includes the sounds: Stops /p, b, t, d, k, g, m, n, ŋ/, fricatives /f, v, s, z, ʃ/, affricates / tʃ, d3/, and other /w, j, l, r/. Still to be acquired at this age are the interdental fricatives [θ] and [ð] and the voiced alveopalatal fricative [3].
In general, the relative order in which sounds are acquired reflects their distribution in the world’s languages. The sounds that are acquired early tend to be found in more languages whereas the sounds that are acquired late tend to be less common across languages. (O’Grady & Cho, 2001)
3. Simplification in production
Until they master the full range of articulatory programs necessary for the variety of legal word shapes in their language, children often fall short of adult pronunciations in their own production. They omit some sounds altogether and substitute some sounds for others. There is considerable consistency in the problems children encounter in production, so their own forms can often be described in terms of characteristic substitutions, assimilations, and omissions, by comparison with the adult targets they are attempting. (Clark, 2009)
a. Substitutions
Children tend to voice consonant sounds in initial position but find it difficult to voice them in final position. As a result, they often voice voiceless initial consonants, as in [bay] for pie; and they appear to devoice final ones, as in [nop] for knob (Joan 1;9; Velten 1943). Some children compensate for their inability to voice stop consonants in final position by using a nasal consonant after the stop at the same place of articulation, as in [dadn] for dad (Labov & Labov 1978), or by combining a nasal consonant with a voiceless stop, as in [piŋk] for pig or [bεnt] for bed. Since voiced nasals like n or m are easier to produce in final position, they seem to offer a convenient way, early on, to maintain voicing at the appropriate place of articulation (Clark & Bowerman 1986). Another common substitution is to use a stop in place of a fricative (Ferguson
1978; Olmsted 1971), as in [tæwi∫] for sandwich (with initial t- for s-), [nayb] for knife (with final -b for -f), [bʌd] for bus (with final -d for -s), or [dun] for soon (with d- for s-). Or occasionally the reverse: A final stop may become a fricative, as when up is produced as [ʌf] (Menn 1971). Other common substitutions include fronting, where the child produces a consonant further forward in the mouth than the intended target, as in [ti] for key or [fit] for thick; and gliding, where children produce the glides w and y, typically in place of the liquids l and r, as in [wæbit] for rabbit. (Clark, 2009)
Lust (2006) declares that there are several kinds of substitution in child language progress such as:
Gliding
Gliding is the substitution of a glide, [w] or [j], for the liquids /ɹ/ and /l/, respectively. This process is specific to English and languages with a retroflex or bunched alveolar approximant (Locke 1983). According to Locke, substitution errors for other rhotics tend to be cases of stopping or fricative substitution. Ingram (1989) gives the following examples for an English learner.
rock→ [wat]
sorry→ [sawa]
lie→ [jaɪ]
Child substitution errors for /ɹ/ are perhaps the best known type of gliding. According to Smit (1993), children under three substitute [w] for /ɹ/ in more than 50% of their productions. Several researchers, including Smit, have also found examples of [w] substituting for /l/, and a few [j]-for-/l/ substitutions. For the sake of brevity, however, the discussion in the next section will focus only on substitutions of [w] for /ɹ/. (Richtsmeier, 2010)
Fronting:
Fronting happens when children produce sounds that should be made in the back of their mouth in the front of their mouth instead. Make the sounds /k/ and /g/. Feel how the back of your tongue hits the back of roof of your mouth? Now make the sound /t/ and /d/. Notice how now it's the front of your tongue that hits the front of roof of your mouth? /k/ and /g/ are made in the back of your mouth while /t/ and /d/ are made in the front. Kids frequently "front" /k/ and /g/ by substituting /t/ and /d/. Go becomes doe, key is tee, and cookie might be tuhtee. Fronting usually disappears by the age of three. (Child Speech Development, 2011)
e.g., substitution of front consonants such as [t] or [d] for back such as velars [k] [g]
‘kitty’→ditty
Stopping
Stopping occurs when children stop air from moving continuously out their mouths. Make the sound /f/ and keep it going. Feel how a stream of air flows between your teeth and lips? Now say the /p/ sound. You should notice that there is a small burst of air for the "p" sound rather than a stream of air. You couldn't keep /p/ going if you tried. You can keep the air going, but the /p/ is over with the second you stop the air slightly with your lips and then release it. Stopping occurs when children stop the air from flowing freely. /f/ and /v/ become /p/ and /b/ so that fan becomes "pan" and video becomes "bideo," while /s/ and /z/ become /t/ and /d/ so that sun becomes tun and "zip" becomes "dip." Stopping also affects the sounds "sh" "ch" and "th." Kids usually stop stopping (ha ha) between the ages of 3.5 and 5, depending on the sound they are trying to stop stopping. (Child Speech Development, 2011)
e.g., substitution of stop consonants for fricatives and affricate
‘shoes’→tuid
Word-initial Voicing
English-learning children often produce word-initial voiceless stops with voicing (Velten 1943). Word-initial voicing has also been documented in learners of Norwegian (Vanvik 1971) and Taiwanese (Linn 1971), as well as in a French-English bilingual (Celce-Murcia 1978). Examples from Velten’s daughter Joan are given below:
pie→ [ba]
toe→ [du]
cap→ [dap]
soup→ [zup]
Word-initial voicing generally occurs with bilabial stops, somewhat less with alveolar stops, and rarely with velars. Voicing of word-initial fricatives is rare. By 3 ½ years of age, most children are correctly producing the voicing contrast. Smit (1993) suggests that word-initial voicing is an infrequent pattern in child speech. (Richtsmeier, 2010)
Word-final Devoicing
Velten (1943) was one of the first researchers to observe that children regularly devoice final consonants. Most often, word-final devoicing occurs for voiced obstruents appearing at the end of a monosyllabic word. Studies of word-final devoicing include Naeser (1970) and B. L. Smith (1979) for English and Pačesova (1968) for Czech. Velten gives the following examples from his daughter Joan, who was acquiring English. (Richtsmeier, 2010)
knob→ [nap]
mud→ [mat]
egg→ [ut]
hose→ [hus]
b. Assimilations
Assimilation refers to the effect of sounds on those preceding or following them within a word or across word-boundaries. The commonest assimilation in young children’s productions is probably reduplication, where children simply repeat the syllable they are articulating, as in [baba] for bottle, [kiki] for kitchen, or [dada] for daddy (Ingram 1974). They may also use partial reduplication, either keeping the vowel the same across syllables (vowel harmony), as in [lidi] for little, or keeping the consonant the same (consonant harmony), as in [babi] for blanket. A third type of assimilation is to add nasality to non-nasal consonants, as in the production of [nam] for lamb, where the initial l- is produced as n-. (Clark, 2009)
According to Lust (2006) there are three types of assimilation as follow:
Regressive assimilation
e.g., ‘duck’→gʌk
‘doggy’→goggy
‘nipple’→mibu
Progressive assimilation
e.g., ‘kiss’ – gik
‘cloth’→gʌk
Reduplication
e.g., ‘daddy’ – dada
e.g., ‘stomach’→ tum tum
c. Omissions
Children often omit the final consonant or even final syllable if it is unstressed, in their early words. Examples like the following are very common: [ba] for ball, [ti] for kick, or [bu] for boot. Leopold also noted forms like [bu] for German Blumen and [pi] for Pipe. They may continue to do this as late as age two-and-a-half or three (Leopold 1939–1949: vol. I). By age three, however, children make fewer than 10% such omissions in word-final position (Winitz & Irwin 1958).
Children also find clusters of adjacent consonants difficult to pronounce and generally attempt only certain parts of them. For instance, in initial clusters with an s plus a stop, for example, st- or sm-, children generally produce just the stop, as in [top] for stop, [mo:] for small, [laid] for slide, and [dεk] for desk. Where a stop is combined with a liquid, they again produce just the stop, as in [gok] for clock, [mik] for milk, or [biŋ] for bring. And if a stop is combined with a nasal, they again focus on the stop, as in [bʌp] for bump or [tεt] for tent. Finally, where a fricative is combined with a glide, they tend to produce only the fricative, as in [fom] for from or [fu:] for few (Smith 1973).
Children generally master some stop consonants (p, g) before fricatives (f) or affricates (ch), and they also generally learn to produce some fricatives before any affricates. (Clark, 2009)
Generally, it can be said that in three phases children delete or omit sounds:
Consonant cluster reductions
e.g., ‘broke’→bok
Final consonant deletion
e.g., ‘it’→i-h
Unstressed syllable deletion
e.g., ‘banana’→ naenə (Lust, 2006)
Conclusion
There are many process to let them succeed in speaking, children need to listen and then practice to take over their own sounds get used to. Babbling is one of the steps that they practice the sounds and utter them, then they need to use all the sounds around them to unite them in order to produce a word. And at early age a baby may go some processes like smplification sounds and what sound is easy they tend to use until they would learn all the sounds in their environment.
References
- Child Speech Development. (2011, April 28). Retrieved May 22, 2013, from talkingkids.org: http://www.talkingkids.org/2011/04/speech-sounds-and-kids-part-2.html
- Clark, E. V. (2009). First Language Acquisition (2nd ed.). New York: Cambridge University Press.
- Lust, B. C. (2006). Child language acquisition and growth. New York: Cambridge University Press.
- O’Grady, W., & Cho, S. W. (2001). Contemporary linguistics: An introduction. csuchico.edu.
- Phonological development. (2011, April 16). Retrieved May 21, 2013, from wikipedia.org: http://en.wikipedia.org/wiki/Phonological_development
- Richtsmeier, P. (2010). Child phoneme errors are not substitutions. Toronto Working Papers in Linguistics, 33, 1-15.
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