It is common for children to make mistakes when they are learning to say new words. It is endearing to hear a young child call a "cookie" a "tookie" or a "dog" a "gog". All sounds have age ranges in which a child should learn to consistently produce the sound correctly (click here for age ranges). A speech sound disorder occurs when a child continues to incorrectly produce the sound(s) past the age range where it is typically attained. In general, there are two types of speech sound disorders, articulation and phonology.
Articulation is simply the process of making sounds. Articulation disorders occur when a child is not able to make individual speech sound(s) correctly past the expected age. Common articulation disorders are:
- Substitutions: replacing one sound with another i.e. "fing" for "thing"
- Omissions: one or more sounds are deleted i.e. "geen" for "green"
- Distortions: a sound no longer sounds like it should. A common example is a lisp where the tongue protrudes through the teeth causing the "s" to sound like a "th".
A Phonological Disorder is a language disorder in which the child has difficulty organizing their speech sounds into a system of sound contrasts. As children learn to speak, they have not yet developed the ability to fully co-ordinate the movements of their tongue, teeth, and lips to produce complex words. As a consequence, certain sounds, sound combinations or transitions from one sound to another may be currently too difficult. Therefore, children below the age of approxiately 4-5 years simplify the production of complex words in predictable patterns. A phonological disorder occurs when a child continues to produce these errors, or processes, past the expected age of extinction.
There are several types of phonological processes. A few examples are listed below. Click the following link for a list of different types of phonological processes and the Elimination of Phonological Processes in Typical Development.
Fronting - child may say "tar" for "car"
Cluster Reduction - child may say "poon" for "spoon"
Stopping - child may say "doo" for "zoo".