Phonological Process Extinction

A Phonological Disorder involves a pattern of speech sound errors. For example, if a child consistently substitutes the “t” sound for the “k” sound, this is the phonological process of “fronting.” Speech sound errors are very common in young children; however, if an error persists after the expected age of extinction, he or she may have a phonological disorder.

Expected ages at which 10 common phonological processes are extinguished in children:

Phonological Process: Example: Gone by Age (Approximately):
1. Fronting “tar” for car“do” for go 3;6
2. Final consonant deletion “do” for dog 3;3
3. Word-final de-voicing “pick” for pig 3;0
4. Cluster reduction “geen” for green“poon” for spoon 4;0
5. Weak syllable deletion “nana” for banana“tatoe” for potatoe 4;0
6. Stopping “sh” “dip” for “ship” 4;6
7. Stopping “j” “dumping” for jumping 4;6
8. Stopping voiceless “th” “ting” for thing 5;0
9. Stopping voiced “th” “dem” for them 5;0
10. Pre-vocalic voicing “big” for pig 3;0


For more information on phonological processing or to learn more about our Speech Language Pathology program, click here.