Childhood Apraxia of Speech

Childhood apraxia of speech (CAS) is a neurological paediatric speech sound disorder. It occurs when a child has difficulty planning/programming speech movements at the level of the brain. Children with CAS may exhibit visible groping with the mouth as they attempt to produce the required movements.

Children with CAS may demonstrate the following types of speech difficulties [Ozanne, 2005]:

  • inconsistent errors - the same word or sound may be said differently each time they say it, with different errors each time

    • word examples: 'ambulance' - "ambance, amlulance, amblan", 'dada' - "deedee, dawdaw, dada"

    •  ​sound example: 'l' at the ends of words - "n, d" or omitted

  • unusual 'prosody' (stress and intonation patterns)

    • add pauses between syllables

    • trouble with 'lexical stress' - stress that conveys meaning (e.g., CONtract vs conTRACT) - putting equal stress on each syllable in a word or putting stress on the wrong syllable 

  • distorted vowels and consonants

  • more trouble with longer words than short ones

  • more trouble with volitional speech (i.e., when asked to say something specific on command) than automatic speech (i.e., saying the alphabet) and imitating sounds/words

  • trouble sequencing sounds and syllables

  • metathesis - switching sounds or syllables around in words (e.g., 'foliage' becomes "foilage")

  • non-speech oral apraxia (NSOA) - difficulty with non-speech movements of the mouth

    • not all children with CAS have NSOA​, so although it might support a diagnosis of CAS, it is not indicate CAS

  • trouble programming the parameters of speech production (i.e., timing, force, spatial parameters)​

    • oral groping (trial and error movements of the mouth)​

    • assymetrical oral movements

A diagnosis cannot be given for CAS until a child is at least 3 1/2 and has enough connected speech. Red flags that may indicate difficulty with motor speech programming in younger or minimally verbal children may include the following (Strand, 2003):

  • vowel distortions

  • small phonemic inventories (only say a limited number of speech sounds)

In young, minimally verbal children (e.g., <3 years), a child may present in such a way that CAS is sometimes suspected (sCAS), or it's deemed that motor speech development should be monitored. The following behaviours and features that are looked for by SLPs and are considered when making differential diagnoses between sCAS, autism spectrum disorders, language delay, or other speech sound delays/disorders:

  • atypical early development (birth to 15m)

  • desire and motivation to speak and interact

  • play skills (should be typical, although the presence of limb apraxia can effect execution of movements needed for play)

  • non-verbal communication skills

  • gap between expressive and receptive language (children with only CAS will generally have good receptive skills)

  • effort when speaking

  • "pop-out" words (say word once and not again)

  • "go-to" sound/word (a word or sound that is used to express many things, e.g., "dee" for everything; and may be strung together to form "sentences", e.g., "dee dee dee")

There are three main causes of CAS:

  1. idiopathic neurogenic speech sound disorder - CAS without any known neurological injury, abnormality, or neurobehavioural disorder

  2. secondary to a neurological injury such as stroke, infection, traumatic brain injury, or tumour

  3. associated with a neurobehavioural or congenital disorder such as autism, epilepsy, or Down Syndome


This section is in development.

There are a number of approaches to treatment for CAS (e.g., Kaufman, PROMPT). It is very important to understand that progress is often slow. Speech is an incredibly complex skill. Treatment for a young child with suspected CAS may take three years or more. The earlier treatment is started, the better.

Frequently Asked Questions

Who diagnoses CAS? In the past, in different areas of Canada and the USA, CAS was diagnosed by neurologists. In the present, it is diagnosed/identified by speech-language pathologists, because it is a communication disorder. You may encounter professionals who are not aware of this change in practice, particularly those who do not work directly with children with motor speech disorders. To learn more about the scope of practice of speech-language pathologists, you can refer to the following documents:

"Audiologists and Speech-Language Pathologists Act"

Government of Nova Scotia

"Scope of Practice for Speech-Language Pathology in Canada"

Speech-Language and Audiology Canada


Apraxia Kids

"Childhood Apraxia of Speech: Information for Parents" (video)

Mayo Clinic

"Childhood Apraxia of Speech"

American Speech-Language-Hearing Association

"Examples of Different Levels of Severity of CAS" (video)

Mayo Clinic

"Differentiating Childhood Apraxia of Speech (CAS) from other types of speech sound disorders"

Dr. Edythe Strand, Mayo Clinic

Videos of Children with CAS

"Darien's Journey with Childhood Apraxia of Speech"

"Severe Childhood Apraxia of Speech 3yr 9mo"

"Childhood Apraxia of Speech: SO MUCH PROGRESS"

Note: Cooper has both CAS and autism

"My daughter's journey with Childhood Apraxia of Speech"

Videos of Adults with CAS

"Growing up with Verbal Apraxia (CAS) - Q&A"

In this short video, Jordan Christian answers some frequently asked questions about growing up with CAS.

"My Battle with Childhood Apraxia of Speech"

Note: Aaron uses the term 'stutter' to describe some of his difficulties with speech. Although there are certainly individuals who have CAS and who stutter, stuttering is not a feature of CAS. He also describes his experience with physiotherapy. Some children with apraxia of speech can also have dyspraxia - motor programming difficulties that affect other areas of the body such as limb movements. However, not all children who have apraxia of speech will have dyspraxia affecting other types of movements. Parents can talk to their pediatrician or family doctor if they suspect dyspraxia.

References on This Page

Ozanne, A. (2005). Childhood apraxia of speech. In B. Dodd (Ed.), Differential diagnosis and treatment of children with speech disorder (2nd ed., pp. 71-82). Whurr Publishers Ltd.

Strand, E. (2003). Clinical and professional ethics in the management of motor speech disorders. Seminars in Speech and Language, 24, 301-11. doi: 10.1055/s-2004-815583