Articulation and Phonology
Articulation and phonetic development refers to a child's gradual acquisition of the ability to produce various speech sounds. Speech sounds are usually first produced around the age of three months with production of vowels. Around 5-7 months children begin babbling which is a more playful vocal way of producing sounds. Following babbling, a child begins to produce strings of sounds and syllables which is referred to as jargon. It is through the production of jargon that first words begin to emerge, usually occurring around 12 months of age.
What is articulation?
Articulation is essentially the way speech sounds are formed in the mouth and then produced. A child with an articulation disorder has difficulty with this task and often substitutes one sound for another (e.g. saying wing for ring), distorts sounds (e.g. shun for sun), or omits sounds within a word (e.g. ca for cat). Traditional articulation therapy involves behavioral techniques, focused on teaching children new sounds in place of error-sounds or omitted sounds, one at a time, and then gradually introducing these new sounds into longer and longer utterances, and eventually into normal conversational speech.
What is phonology?
Phonology is essentially the patterns in which speech sounds are developed. As a child's speech develops he/she will ordinarily sort out the rules for producing sounds correctly. Children who do not develop the patterns of speech normally can be difficult to understand. Phonological therapy involves focusing on the development of patterns of sounds instead of individual sounds as with articulation therapy.
How easy should it be to understand a child's speech?
Intelligibility is the ability of one person to understand what another person is saying. A general rule of thumb of a child's intelligibility by an unfamiliar listener is:
- a child at 19-24 months should be understood 25 to 50% of the time
- a 2-3 year old child should be understood 50-75% of the time
- a 3-4 year old child should be understood 80% of the time
- a 4-5 year old child should be understood 90 -100% of the time
When should my child be able to produce individual speech sounds?
- at age 3: h, w, m, n, b, p, f
- at age 4: d, y, k, g, ng
- at age 6: l, j (as in jam), ch, sh, v, r, s, t, z, th (as in think)
- at age 7: zh (as in garage), th (as in feather)
Please bear in mind that the above normative information is just a general rule of thumb and there is a wide range of normal development. When in doubt about your own child's articulation/phonological development an assessment by a speech-language pathologist will assist you in determining if your child is developing "on track."
The above developmental ages were compiled from A. Pena Brooks and M. Hegde, in Assessment and Treatment of Articulation and Phonological Disorders in Children and The Developmental Articulation Profile.