Childhood apraxia of
speech (CAS) is a neurological childhood (pediatric) speech sound
disorder in which the precision and consistency of movements underlying
speech are impaired in the absence of neuromuscular deficits (e.g.,
abnormal reflexes, abnormal tone). CAS may occur as a result of known
neurological impairment, in association with complex neurobehavioral
disorders of known or unknown origin, or as an idiopathic neurogenic
speech sound disorder. The core impairment in planning and/or
programming spatiotemporal parameters of movement sequences results in
errors in speech sound production and prosody.
Thus we see from this definition:
1. CAS does indeed exist
2. There are several possible causes.
3. It appears to be a problem of planning and/or programming the
movements for speech.
The position statement and technical report also tell us that CAS may
co-exist with:
Oral Apraxia - problems with sequencing the movements for non-speech
oral activities such as chewing and swallowing.
Dysarthria - problems of muscle weakness
Some
useful links for more information:
See the website for the Childhood Apraxia of Speech Association of North America at http://www.apraxia-kids.org/
For a detailed analysis of the position statement and some
suggestions for assessment and treatment of this condition see http://www.slpinfo.org/product.html
And Shelley Velleman has also provided some useful information
at: http://people.umass.edu/velleman/cas.html
Caroline Bowen provides an excellent discussion of speech sound
disorders in children that includes a discussion of CAS. See http://speech-language-therapy.com/phonol-and-artic.htm