Childhood apraxia of speech: signs, diagnosis and treatment

Childhood apraxia of speech (CAS) is a motor speech disorder. The child knows what they want to say, but the brain has difficulty planning and sequencing the precise movements needed to say it, even though the speech muscles are not weak. Speech-language pathologists listen for three core features: inconsistent errors, difficulty moving smoothly between sounds, and unusual rhythm or stress. CAS is uncommon, diagnosis takes a careful assessment and often more than one session, and therapy that is frequent and movement-focused can help.

What CAS is

The American Speech-Language-Hearing Association’s 2007 technical report defines CAS as a neurological childhood speech sound disorder in which the precision and consistency of the movements underlying speech are impaired, in the absence of muscle weakness or other neuromuscular problems. In plain language, the instructions from the brain to the mouth are unreliable. The child may say a word clearly once and then be unable to say it the same way again.

A few points parents often find reassuring:

• CAS is not caused by anything a parent did or did not do.
• It is not laziness, stubbornness or a lack of effort. Children with CAS usually work harder to speak than their peers, not less.
• It is not a problem with understanding. Many children with CAS understand language much better than they can express it, which can be frustrating for them.
• It can occur on its own or alongside other conditions, and in some children a cause is never identified.

The ASHA Practice Portal describes CAS as uncommon, citing estimates of around 1 to 2 children per 1,000. Most children with unclear speech have a phonological or articulation difficulty instead, which is why an assessment is the first step rather than an assumption.

The core features SLPs listen for

The 2007 ASHA technical report identified three features that have the widest agreement among researchers and clinicians. An SLP looks for all three, across a range of speaking tasks.

1. Inconsistent errors on consonants and vowels in repeated productions of the same word. Asked to say “banana” five times, a child with CAS might produce it five different ways. A child with a phonological delay tends to make the same error every time.
2. Lengthened and disrupted transitions between sounds and syllables. Moving from one sound to the next is effortful. There may be pauses or breaks between syllables, or the sounds may seem to be produced one at a time rather than flowing together.
3. Inappropriate prosody. Prosody is the rhythm, stress and melody of speech. Children with CAS may put equal stress on every syllable, so that speech sounds flat or “robotic”, or stress the wrong syllable.

Other signs that clinicians commonly report, and that the ASHA Practice Portal lists, include:

• vowel errors, which are unusual in other speech sound disorders after age 3,
• “groping” or searching movements of the lips and tongue before speaking,
• more errors as words get longer or more complex,
• a small set of consonants and vowels for the child’s age,
• difficulty imitating words, even simple ones,
• automatic phrases (“bye bye”, “I love you”) that come out more clearly than new or requested words, and
• in toddlers, limited babbling and late first words.

None of these signs is specific to CAS on its own. Several of them also appear in children with a phonological delay or a language delay, which is why the pattern across many features matters more than any single sign.

How CAS differs from phonological delay and dysarthria

Three conditions can make a child’s speech hard to understand, and they are treated differently, so telling them apart is central to the assessment.

Phonological delays are by far the most common of the three. Our guide to phonological processes describes the typical patterns and when they usually fade. Dysarthria is associated with conditions that affect muscle control, such as cerebral palsy, and is usually identified alongside a medical diagnosis. A child can have more than one of these at the same time, and some children have CAS together with a language delay.

Why diagnosis needs an SLP and often several sessions

There is no blood test, scan or single questionnaire for CAS. The diagnosis rests on a detailed motor speech examination carried out by a registered speech-language pathologist. The ASHA Practice Portal describes the components, which typically include:

• repeating words of increasing length (for example “pop”, “puppy”, “puppet”, “puppeteer”),
• repeating the same word several times to check consistency,
• rapid syllable sequences such as “pa-ta-ka”,
• listening to connected speech and to automatic phrases,
• assessing stress and rhythm,
• an examination of the lips, tongue and jaw at rest and in movement,
• language assessment, and
• a hearing test, usually by an audiologist.

Several things make a single session insufficient. A child who says very few words does not provide enough speech to judge consistency, so a clinician may describe “suspected CAS” and reassess once the child has more words. Features can change as a child grows. Shyness or fatigue in a new setting can hide or exaggerate signs. And because CAS shares features with other disorders, clinicians often want to see how the child responds to a short period of therapy before settling on a label. This is normal practice, not a sign that something is being missed.

Physicians such as developmental pediatricians or neurologists may be involved to look for related conditions, but the speech diagnosis itself is within the scope of speech-language pathology. In Ontario, anyone using the title must be on the CASLPO Public Register. Our guide on checking a speech-language pathologist’s registration explains how.

Treatment principles

The ASHA Practice Portal summarizes the evidence as favouring approaches built on principles of motor learning. The practical implications for families are:

• Frequent, intensive sessions. Several short sessions a week are generally preferred over one long one, because motor learning depends on repeated practice close together.
• Many trials per session. The child practises whole words or syllable sequences dozens of times, with the clinician shaping each attempt.
• Movement sequences, not isolated sounds. The focus is on the transitions between sounds, which is the core difficulty, rather than on perfecting a single sound.
• Multisensory cues that are gradually faded. The clinician may slow down, use touch cues on the face, exaggerate mouth shapes or use hand gestures, then reduce support as the child improves.
• Feedback that shifts from frequent to occasional so the child learns to monitor their own speech.
• Practice that varies in rate, loudness and stress, so skills transfer to real conversation.

Named approaches that follow these principles include Dynamic Temporal and Tactile Cueing (DTTC), Rapid Syllable Transition Treatment (ReST), integral stimulation and the Nuffield Dyspraxia Programme. ASHA notes that these have the most supporting research among CAS treatments. By contrast, non-speech oral motor exercises such as blowing, tongue wagging or chewing tools are not supported by evidence for improving speech, and ASHA advises against relying on them.

Two other points are worth knowing. First, augmentative and alternative communication (pictures, signs or a speech-generating device) is often introduced alongside speech therapy so the child can communicate now. Research summarized by ASHA indicates it supports rather than replaces spoken language. Second, children with CAS are at higher risk for later difficulties with reading and spelling, so clinicians usually keep an eye on early literacy skills. Many children with CAS make meaningful progress with sustained therapy, but outcomes vary and no one can promise a particular result.

The Ontario pathway

For children who have not yet started school, the free Preschool Speech and Language Program is the usual starting point. Families self-refer, no doctor’s referral or diagnosis is needed, and the assessment is part of the service. In many regions, SmartStart Hubs are the single access point. Once a child starts school, support shifts to school board SLP services and, through Children’s Treatment Centres, School-Based Rehabilitation Services. Because CAS therapy depends on frequent practice, some families add private therapy, which OHIP does not cover but many extended health plans partly do. Where a child also has an autism diagnosis, Ontario Autism Program core clinical services funding can be used for speech-language pathology delivered by a CASLPO registrant. Our guides on how to get speech therapy in Ontario and the cost of speech therapy in Ontario go into the details.

What you can do at home

• Accept every attempt. Respond to what your child means, then model the word clearly once. Avoid asking for repeats, which can add pressure to speech that is already effortful.
• Offer choices and gestures. “Milk or juice?” with the items in view lets your child answer with a point, a word or both, and reduces frustration.
• Keep practice short and frequent once an SLP has given you specific words or phrases. Five minutes two or three times a day suits motor learning better than one long session. The articulation practice tool can be set to a small set of target words.
• Use routines. Repeated phrases at bath time, bedtime and mealtimes (“all done”, “night night”) give natural practice of the same movement sequence.
• Track what you notice. The milestone checklist and the speech sound checker can help you describe your child’s speech to a clinician. They are general information tools, not screening tests.
• Protect confidence. Make sure siblings and relatives do not correct or imitate. A child who feels safe talking will practise more.

If your toddler is late to talk and you are not sure whether speech sounds or language is the bigger concern, our guide on late talkers is a good companion to this one. Whatever the eventual label, earlier support is generally easier, and an assessment gives clarity either way.