There are many types of speech problems in children. The speech-language pathologist will complete an evaluation to understand the type of speech disorder a child has, a process known as differential diagnosis. Accurate differential diagnosis is important because it guides the therapist in selecting the correct method of treatment.
Talking requires complex and well-coordinated movements of the lips, tongue and other structures involved in speaking. The muscles must move in the right direction with the correct speed and force to produce sounds for understandable speech. The brain controls the planning and programming of these muscle movements. When the speech-language pathologist observes signs of difficulty with planning and programming movements for speech, the child is given the diagnosis of CAS. CAS is simply a label for this specific type of speech disorder.
In order for the speech-language pathologist to observe and evaluate the child’s speech motor planning and programming skills the child will need to:
If the child does not have intentional communication and does not attempt to imitate, the diagnosis of CAS is not possible. For these children, it is more likely that other factors like joint attention or listening comprehension should be the initial focus of treatment.
When the child can attempt imitation of speech, then a dynamic motor speech examination is the best method to diagnose CAS. A dynamic motor speech assessment evaluates the child’s ability to plan and program movements necessary for speech production. It also reveals how the child benefits from cues provided by the therapist, an indicator of the expected rate of treatment progress.
It is important to understand that CAS is both under diagnosed (some children who have it are not diagnosed) and over diagnosed (some children who do not have it are given the diagnosis). In both instances, incorrect diagnosis can result in a therapy plan that is not addressing the primary, underlying cause of the communication problem.
What speech characteristics indicate CAS?
The following characteristics are the best indicators of CAS:
The following characteristics occur from a variety of speech sound disorders and are not good indicators of CAS:
If your child has been given a diagnosis of CAS based on these symptoms, you should have a follow-up discussion with your speech-language pathologist. Remember, CAS is a rare disorder, and the speech-langauge pathologist may be unfamiliar with the best methods of assessment. You may want to talk to your therapist about your research and share resources you have found, such as this website.
What does the label “suspected CAS” mean?
This label may be appropriate to use when a child shows one or two characteristics of CAS but cannot participate in a motor speech examination so the clinician to confirm or rule out CAS. This is most common with very young children. If your child receives a diagnosis of “suspected CAS”, here are some questions to ask the therapist:
The following situations may indicate a need for further discussion with your therapist or even a second opinion:
Can CAS occur with other types of disorders?
CAS can occur in isolation with no identifiable underlying neurological disorder (known as idiopathic CAS), or it can occur with other developmental and neurological disorders. Children with CAS may also have delays in expressive language skills and in development of the rules that govern how sounds are used in a language (known as phonology).
CAS occurs more often in children with certain disorders, such as Galactosemia and Down Syndrome. Although children with autism were once thought to be more at risk for CAS, research indicates that is not the case.
When CAS occurs in isolation, assessment and treatment can focus just on the CAS. When CAS occurs with other developmental disorders, it is important that the diagnosis and treatment of CAS take into consideration other developmental skills.
Here are some questions to ask your therapist if your child has both CAS and another developmental or neurological disorder: