Red flags for CAS in young children

Childhood apraxia of speech is a complicated disorder that can be difficult to identify, due to its huge variability in presentation and similarities with phonologically-based speech sound disorder. The task is even more challenging when working with very young children with limited vocalizations. But what if there were specific red flags to look for in young children, similar to those we use for suspected autism or hearing impairment?

Overby et al. reviewed hours of home video footage of infants and toddlers to determine if there are clinical red flags that are reliably associated with a later diagnosis of CAS or speech sound disorder. Turns out, the speech characteristics of young children who later receive a diagnosis of CAS are markedly different from those of typically developing children. Between birth and 24 months, the following atypicalities were observed in children with a later diagnosis of CAS: 

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  • Limited vocalizations with few “speech-like” sounds

  • Lack of a speech-like consonant by 12 months

  • Limited consonant repertoire

    • specifically, < 3 consonants at 8–16 months and/or < 5 consonants at 17–24 months

  • Lack of velar productions and favoring of bilabials

  • Favoring stops & nasals

  • Limited syllable structures

    • productions between 13–18 months were largely vowels, lacking CV or CVC structures

As an early interventionist, being aware of these red flags may help to tease out language versus speech difficulties and provide appropriate interventions at a younger age. Infants and toddlers with a later diagnosis of speech sound disorder showed a similar, but less severe profile, and the results did not quite reach significance. However, it is important to be aware of this pattern so that we can provide all children with the most optimal early intervention services.

 

Overby, M.S., Caspari, S.S., & Schreiber, J. (2019). Volubility, consonant emergence, and syllabic structure in infants and toddlers later diagnosed with childhood apraxia of speech, speech sound disorder, and typical development: A retrospective video analysis. Journal of Speech, Language, and Hearing Research. doi: 10.1044/2019_JSLHR-S-18-0046.

Throwback (2009 & 2015): Speech delay? Language delay? Measuring it, and what’s common in toddlers with autism

For all the SLPs who work with younger children with autism (so ages 2–4), this one’s for you! The following is a review of two studies from the last decade that can help you understand and characterize the various expressive language profiles you may see in these children, as well as brainstorm therapy!

The first paper reports on a meeting of experts in early autism and language development. (NOTE: If you’re a science groupie who gets googly-eyes for big names, pop on over and look at the author list; #sofamous). The purpose of the group was to create a list of measures of the expressive spoken language of children with autism from 12 to 48 months of age. These benchmarks can be used in assessment (as part of a comprehensive assessment including parent report, natural language samples, and/or direct assessment), or to guide intervention.  

In the article, you’re provided with a chart (see Table 1) divided into “First Words (12–18 mos)”, “Word Combinations (18–30 mos)”, and “Sentences (30–48 mos)”. Then within each of those categories, you have measures for:

  • Phonology

  • Vocabulary

  • Grammar

  • Pragmatics

…and within each of those categories, the child must meet at least one marker, at minimum, to be placed within that category.  

So, for example, for the Sentences (30–48 mos): Phonology section, markers are:

  • 70%+ intelligible from a speech–language sample

  • Consonant inventory of at least 16–24 different consonants (75% correct), from a speech–language sample

  • Age equivalent score of at least 36 months on a standardized test (e.g. GFTA or other)

…and the child must meet the intelligibility criteria or the standardized test criteria in order to be considered as meeting that benchmark. 

Then, you’d look across the other measures to (so vocabulary, grammar, and pragmatics) to see where they fit in each of those categories. 

Overall, this provides a really nice way to consider data from multiple sources (and, importantly, to know which pieces of data to prioritize), and supports SLPs in describing the spoken expressive language of kids with ASD in a systematic fashion.

 

So, how do most kids with ASD perform with these benchmarks?

Aha! That’s what the next paper looked at.

The authors of this article evaluated over 100 kids ages 2–3 years old using the “Spoken Language Benchmarks” (what we just described! From the last paper.) They found:

Considering phonology, vocabulary/grammar, and pragmatics as three separate skill sets…

  • Most of the children’s lowest score was in pragmatics (of course, right?! They have autism…)

  • And the two most common profiles were:

    • phonology > vocabulary/grammar > pragmatics

    • phonology = vocabulary/grammar > pragmatics

    • See Table 3 for six other profiles observed, too! That table is really fascinating, seeing what’s most versus least common…

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So let’s chat about this. Basically, they found that, “… phonology tends to be relatively intact for most individuals whereas pragmatic difficulties are nearly universal…” and “… in terms of pragmatics, 88% of the children fell into the Prelinguistic group, which reflects a developmental level of less than 12 months of age.”

Nearly half of the kids achieved higher phonology scores than vocabulary/grammar and pragmatics. So it’s an area of relative strength! And when we think about kids with ASD on our caseloads, I’m sure you can remember many kids fitting this profile—good speech skills, and expressive language and/or pragmatics not so much.

Overall, being able to weigh relative strengths of phonology, vocabulary, grammar, and pragmatics for our kids with ASD helps inform treatment, and also could be quite helpful in identifying which types of treatment tend to help which types of children with ASD in both clinical work and research.

 

Ellawadi, A.B., & Weismer, S.E. (2015). Using Spoken Language Benchmarks to Characterize the Expressive Language Skills of Young Children With Autism Spectrum Disorders. American Journal of Speech–Language Pathology, 24, 696–707.

Tager-Flusberg, H., Rogers, S., Cooper, J., Landa, R., Lord, C., Paul, R… Yoder, P. (2009). Defining Spoken Language Benchmarks and Selecting Measures of Expressive Language Development for Young Children With Autism Spectrum Disorders. Journal of Speech, Language, and Hearing Research, 52, 643–652.

Throwback Pub (2017): Treating CAS in the under-three crowd

Childhood Apraxia of Speech. Where to begin? If you’ve tried searching for treatment strategies in very young children, like here or here, or read ASHA’s Technical Report (though that one’s now a decade old…), you know it’s slim pickings. There are good treatment strategies for older children. But, ah, hellooo, what do we do before age four?

This study describes the Speech Motor Learning (SML) approach and tested its effect on a 33-month-old boy with CAS. SML is based on the Four Level Framework (FLF) of speech sensorimotor control. The basic idea in the FLF is that there are four phases in processing speech: linguistic-symbolic planning, speech motor planning, speech motor programming, and execution. The motor and sensory systems communicate to develop motor plans and adjust motor programs. See the article for a synopsis of the FLF.

SML uses principles of motor learning to train sound sets of gradually increasing difficulty. The (very basic) idea is to build “core motor plans” for each speech sound, and then build the flexibility to execute those motor plans in varying phonetic contexts. Nonword targets are based on stimulability, accuracy of production, and developmental appropriateness, and are introduced in a series of stages. The SLP trains a small set of stimulable consonants and vowels, and targets CVCV non-words in five levels of increasing difficulty as the child masters each level. For example, the first level might include nonwords like /bɪbu/, /bɪbi/, /bɪba/ and then slowly increase complexity to nonwords like /bɪdu/, /bɪmu/, /bɪgu/.

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Does it work? Well, maybe. The boy in this single case study had been involved in an early intervention program using the Hanen program for over a year with minimal improvement in his articulation. He had normal hearing as screened by an audiologist, and scored within normal range on the Rossetti Infant-Toddler Language Scale. Treatment was provided for 9 weeks, and the authors examined whether the treated sounds could be correctly produced in words or nonwords. The child decreased his total number of errors per word and non-word, and improved his production in the first set of targets and some of the second set, but the authors hesitated to attribute all of his progress to the treatment alone because his baseline scores were variable.

For more on the SML approach and FREE software for creating CVCV and CVC stimuli, see the lead author’s website here.

 

van der Merwe, A., & Steyn, M. (2017). Model-driven treatment of childhood apraxia of speech: Positive effects of the speech motor learning approach. American Journal of Speech-Language Pathology, 1-15.