Childhood Apraxia of Speech - CAS
Inconsistent errors on consonants and vowels in repeated production of syllables and words.
lengthened and disrupted coarticulatory (a speech sound influenced by and becomes similar to a preceding or
following speech sound) transitions between sounds and syllables.
Inappropriate prosody (the rhythm and stress of speech - affects the form of speech,
whether question, statement or command).
Childhood Apraxia of Speech, or CAS, is a severe speech disorder found in young children. CAS has several
different titles that are currently used. Other names for CAS are developmental verbal dyspraxia, developmental
dyspraxia of speech and just simply, dyspraxia.
In my experience, some health professionals don't have a clear understanding of CAS and confuse it with other
speech disorders, such as the more common developmental phonological disorder.
A concern is that over the years
I have spoken to a number of parents whose children have been given a diagnosis of CAS from health professionals, sometimes after
only a brief 20 minute consultation.
It's important to acknowledge that childhood apraxia of speech is difficult to diagnose and often requires several different
assessments, observation of the child's speech over time, and quite a bit of expertise from qualified clinicians who
understand its distinguishing features. I don't think CAS is something that can be accurately diagnosed in a 20 minute session.
Children with child apraxia of speech have some form of disruption of their speech motor control. It is believed that the impairment lies somewhere between the phonological encoding and the motor
planning areas of an individual's speech processing system
That is, in typical conversational
speech, individuals with dyspraxia will have distorted or even unintelligible speech due to difficulty in rapidly
moving their articulators (tongue, teeth, lips) in an ordered and sequenced manner.
It is the combination of motor planning problems and phonological linguistic difficulties which is a distinguishing feature of CAS. However, a recent report (2007) from the ASHA (American Speech and Hearing Association) concluded in fact that, currently, there is no single set of diagnostic
features (or standardized tests) that can differentiate CAS from other child speech sound disorders.
However, there was consensus among ASHA committee members that there were three segmental (discrete speech units such as
phonemes - vowels and consonants) and suprasegmental (phonemes that are not distinct units of sound
that include tone, stress and prosody in connected speech) features that were consistent in children with CAS.
The three features are...
The ASHA committee stated that the above features alone are not to be considered as sufficient signs of CAS. This is due
to the understanding that each child with CAS, phonological disorder, or both may have a unique profile that will be
affected by task complexity, the severity of the child's speech/phonological errors and his/her age.
American Speech-Language-Hearing Association. (2007). Childhood Apraxia of Speech (Technical Report)
Available from www.asha.org/policy
Apraxia-KIDS website. SLP start guide to Apraxia.
Available from http://www.apraxia-kids.org
Bowen, C. (2009) Children's Speech Sound Disorders. Wiley-Blackwell John Wiley & Sons
Ladefoged, P. (1993) A Course in Phonetics, Third Edition. Harcourt Brace College Publishers
Royal College of Speech and Language-Therapists (2011) RCSLT Policy Statement: Developmental Verbal Dyspraxia
Available from www.ndp3.org/documents/rcslt2011dvdPolicyStatement.pdf
Williams, L.A. McLeod, S. & McCauley, R.J. (2010) Interventions in Speech Sound Disorders in Children.
Paul H. Brookes Publishing Co.
Content Updated 1/12
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