What is Childhood Apraxia of Speech?

Was your child a late talker?.... Didn't babble as an infant?... Does he have difficulty imitating words?... Are her sound errors inconsistent?  These are just a few possible signs and symptoms of  Childhood Apraxia of Speech (CAS), but they can also be indicators of other speech or language disorders.  So, how can you tell if your child has CAS or not?

Let's start with some definitions...

Language vs. Speech:

When a child has difficulty understanding others (receptive language), or meaningfully using words and sentence to share thoughts and ideas (expressive language), then he or she may have a language delay or disorder.

When a child is unable to produce speech sounds to correctly form words,  then he or she may have a speech delay or disorder. CAS is one such speech disorder. However, there are several more common types of speech disorders that may also cause a child to have difficulty producing sounds.  Here are 3 main types of speech disorders that can sometimes be difficult to differentiate from one another:
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1. Articulation Delay: Young children often exhibit articulation errors by substituting,  omitting. or distorting particular sounds.  For example, making "w" for "r" sounds (e.g., "wun" for "run"), "d" for "th" (e.g., "dat" for "that"), and lisping of "s" (e.g., "thoup" for "soup") are errors of articulation.  If these errors continue past the expected age of acquisition, then the child may have an articulation delay. By the age of 8 all typically developing children should be able to pronounce all English sounds correctly.
2. Phonological Process Disorder: This type of speech disorder involves "patterns" of sound errors called "phonological processes", rather than errors specific to just one or two sounds.  Children with phonological disorders produce sound errors that are typically very consistent when they speak.  For example, they may consistently substitute sounds made in the back of the mouth, like "k" and "g", for sounds produced in the front of the mouth, like "t" and "d" (e.g., "tandaroo" for "kangaroo" or "tup" for "cup"). Typically developing children often use these "simplified" ways to produce speech when they're younger, but like articulation disorders, if these errors continue as they become older, the child may have a phonological disorder.
3. Childhood Apraxia of Speech is a much less common, neurologically based speech disorder. (Some sources indicate that CAS affects 1 – 10 in 1000 children or 3 – 5 % of speech-impaired preschoolers.) Children with CAS have problems saying sounds, syllables, and words, not because of muscle weakness or delayed development, but because the brain has problems planning the movements of the body parts needed for speech (e.g., lips, jaw, tongue).  Therefore, we call it a motor speech disorder. Children with CAS display errors that are typically inconsistent, the child may appear to be groping when attempting to produce sounds, he/she may have vowel sound errors, and have more difficulty upon imitating words.  Click here for more signs/symptoms of CAS.

So, how can you tell if your child has CAS?

The first step is finding a Speech Language Pathologist experienced with motor speech disorders.  In the U.S., SLPs are the most qualified professionals who can and should differentially diagnose CAS from other speech disorders.  I often hear of parents receiving an Apraxia diagnosis from their pediatricians or neurologists, but these professionals tend to use CAS as a "catch-all" term for children who have severe delays in speech or language and don't have the training or expertise to differentially diagnose.  

A comprehensive evaluation conducted by a Speech Pathologist experienced with CAS will include:

1. a thorough case history
2. oral motor/mechanism exam
3. assessment of receptive and expressive language abilities
4. in-depth speech sound assessment.  

It's important to note, however, that if only a limited speech sample can be obtained, a firm diagnosis will be challenging. In cases where children have very limited or no speech, especially with children younger than 3 years of age, SLPs often note "suspected" CAS until the child has enough speech to analyze. But, the provision of appropriate therapy should not be delayed.  Early intervention is critical, no matter the particular diagnosis.

Why is an accurate diagnosis important?  2 Reasons:

1. An accurate diagnosis will determine what type of intervention will be most effective.  There are numerous therapy approaches to treat different types of speech sound disorders. But, for example, using a phonological treatment approach to treat a motor speech disorder will not be as effective as those strategies and techniques that are designed to improve the motor planning aspects of speech.  
2. Children with CAS typically require individual, frequent and intensive therapy to make acceptable gains. For children with articulation or phonological deficits, receiving 1-2 speech therapy sessions a week may be sufficient.  However, the consensus among most experts is that frequent and direct intervention 3-5 times a week is most effective for children with CAS.

This is only a brief overview about differentiating CAS from other speech disorders. For more detailed information about Childhood Apraxia of Speech please visit these helpful sites:

​American Speech Language Hearing Association (ASHA)

Apraxia-Kids