Phonology is the sound system of language. Phonological processes are simplifications used by children not capable of producing adult speech patterns. A disorder in this area results in a lack of understanding of the rules for how sounds fit together to make words and use simple processes to simplify words. Children who have phonological disorders are at risk for reading and learning problems.
Phonological processes can be broken up into three categories: syllable structure, substitution, and assimilatory processes. These groups are further divided into more specific delays seen in normal children's developing speech. Below are examples of these processes.
Velar fronting: The /k/ and /g/ sounds are articulated by making contact between the back of the tongue and the velum or soft palate. Sometimes children produce these sounds as /t/ and /d/ respectively, making contact between the front of the tongue and the alveolar ridge just behind the front teeth. Children with velar fronting may pronounce car as tar or gas as das.
Palatal fronting: This is similar to velar fronting, except that palatal sounds /sh, zh, ch, j/ are affected. (shop becomes sop and chair becomes tair)
Consonant cluster reduction: This is when a child omits a sound in a consonant cluster, which is two or more consonants in a sequence without any vowels between them. (spoon becomes poon, stop becomes top, green becomes geen, nest becomes nes)
Stopping: Stopping occurs when fricative consonants /s, z, f, v, th, sh, zh/ or affricate consonants /ch, j/ are replaced by a stop consonant /p, b, t, d/. (sun becomes tun, thumb becomes dum)