What is articulation and phonology?
Articulation is the movements of the organs of speech (lips, teeth, tongue) that modify the breath stream resulting in speech sounds. An articulation disorder occurs when a child does not produce sounds correctly by a certain age. This could be due to an oral motor deficit (muscle weakness).
Phonology is the study of rules governing the sound system of the language, including speech sounds, speech sound production, and the combination of sounds in meaningful utterances. Phonological processes are patterns of speech found in typically developing children. If a child has a phonological disorder, the child has phoneme errors that can be grouped as a pattern of sound errors.
What are the characteristics of an articulation disorder?
An articulation disorder is referred to as abnormal productions of speech sounds consisting of: substitutions of one sound for another, omission of sounds, sound distortions and/or sound additions. It is typical for young children to make speech sound errors. However, every sound has a different range of age when the sound should be mastered. It is when a child reaches that age and the sound is not mastered, that there is an articulation disorder.
Speech Sound Development Chart
/b, d, h, m, n, p/
/b, m, n/
/f, g, k, t, w/
/f, g, k, ng, p, t/
/b, d, g, k, n, t/
/ch, j, l, s, sh, y, bl/
/ch, j, l, s, sh, z/
/l, ng, ch, j, s, sh, r, v, z/
/r, v, br, dr, fl, fr, gl, gr, kl, kr, pl, st, tr/
/z, sl, sp, sw, th/
Speech sound norms taken from Goldman Fristoe Test of Articulation 2, 2000- at which 85% of the standardization sample correctly produced the consonant and consonant cluster sounds.
What are the characteristics of a phonological disorder?
A phonological disorder may be characterized as multiple speech sound errors that share a common syllable structure or phoneme class. An example of this would be final consonant deletion where all final consonants of words are deleted. Instead of a child saying 'toad', it becomes 'toe'.
Below is a link to an informational chart on phonological processes and the approximate age of elimination.
Below is a link on speech sound disorders.