Speech or articulation errors occur when sounds are omitted, distorted, or substituted. When an individual omits, distorts, or substitutes sounds, their speech may sound garbled or slurred. Children who misarticulate sounds may develop spelling and reading issues as they struggle to match the printed letter with their mispronounced speech sound. Individuals and adults at school, work, and in social situations may converse less with a person who is difficult to understand.
Phonological errors occur when the rules for groups or sound classes are in error. An individual may produce frontal tongue tip sounds such as “t” and “d” for all their back tongue sounds “g” and “k” (det for get, tate for take). They may produce all their blowing sounds “sh,” “ch,” “s,” “z,” as if they were stopping sounds “t”, “d” (ton for sun, doe for so). When individuals produce entire classes of sounds in error, their speech is often extremely difficult to understand, and both the speaker and listener may become very frustrated.