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Can I Use the Complexity Approach with Children with Childhood Apraxia of Speech, CAS?

Jul 17, 2022

A child can have co-occurring speech sound disorders.  A child can have Childhood Apraxia of Speech (CAS) and have some phonological pattern errors or articulation errors.  A child can have CAS and have dysarthria.  The  assessment process will help determine the role and impact that each disorder plays in that child's speech impairment.  

I am currently working with a 4 year old boy with CAS who was also demonstrating the phonological pattern of stopping.  Stopping is when a child produces a stop consonant /p, b, t, d, k, or g/ in place of a fricative /f, v, th, s, z, sh/ or affricate sound /ch or j/. 

He was able to produce the /f/ and /s/ sounds in isolation, though had difficulty producing them in words.  He produced "shoes" as "dooz", "socks" as "docks" and "four" as "pour".  He was stimulable for the /f/ sound in simple words, when given multi-sensory cueing.  We used minimal pairs along with principles of motor learning to elicit the /f/ sound in initial position.  I used visual cues with speech sound cue cards, along with slow rate and simultaneous productions (having the child say the word together with you). Using principles of motor learning, we got in many repetitions of the /f/ sound in simple words during play activities.  

The /s/ sound however, proved to be more challenging.  He was able to produce the /s/ sound in isolation but when put into a word, he produced it as a /ts/.  He was somewhat successful in final position of the word i.e. ice, mess, but his productions were inconsistent.

Then I thought of trying the complexity approach with him.  What if I focused on more complex targets which may then lead to production of less complex targets?  I chose the /sl/ cluster.  Most children will omit the /s/ sound in the cluster i.e. lide for slide, and do not replace it with a stop sound.  Additionally, there is a way to classify sounds by distinctive features, which is called markedness.  One of the rules of markedness is that clusters imply singletons.  Therefore, working on a cluster will help the child acquire the singleton, in this case the /s/ sound.

I chose a few common /sl/ clusters such as "sleep", "slow", and "slide".  These were easy to practice with any open ended toy that has little people or animal figures.  Again, I used visual cues along with slow rate and simultaneous productions.  He was stimulable for those words and we started seeing success with the /s/ sound.  After several sessions, we saw carryover to simple /s/ words such as "see" and "sock".  Due to the apraxia component we needed to practice the words many times in blocked practice and the parent practiced it with him at home.  We continue to see progress to other words that we have not directly targeted.  Mom reported that he is starting to say "yes" instead of "yet".  

Why don't we utilize the complexity approach more often with children who have CAS? Firstly, there is currently no research supporting this method for children with CAS, so we must proceed cautiously. Secondly, CAS treatment typically emphasizes words with less complex structures to enhance the child's vocabulary rapidly and boost their confidence. Indeed, some children may lack the resilience needed to tackle more intricate target words.

That being said, there are occasions when I intentionally opt for difficult words to stimulate the motor system, aiming to trigger transformations in movement patterns and vocabulary. For instance, I enjoy focusing on diphthongs – syllables containing two vowels like in "out" or "eye". If the child can articulate both vowel sounds, I encourage it! Diphthongs are prevalent in many functional, power words like down, out, mine, hi, and bye.

As clinician's we need to choose the approach that works for each individual client.  For this client, the complexity approach was right for him and helped him be successful when other approaches did not.

I encourage you to learn more about the complexity approach and keep it in your toolbox.  

Listen to the SLP Now Podcast episode Crash course on the complexity approach.  Jennifer Taps Richard, M.A., CCC-SLP, from provides a comprehensive overview of the implementation of the complexity approach.

Check out the course from Kelly Farquharson, PhD, CCC-SLP  In her bio there is a link to her embracing expertise series.  She has several short courses on phonological interventions including the complexity approach.  Her instagram page has many posts that are packed with great information to help you treat speech sound disorders.

A great TPT resource on the complexity approach that I highly recommend is from Suzanne @playingspeech  Here is a link to the resource She provides you will all the research based information and guides you in the decision making process on whether this approach is right for your client.  She even has a freebie to get you started

I hope the information in this blog post will challenge you to individualize your treatment.  Therapy is not a cookbook.  As a clinician we need to use our clinical skills to find the right treatment for each client. 


Free Target Selection Handout for CAS

Learn how to choose target words for minimally verbal children, understand

multisensory cueing, and other do's and don'ts in apraxia therapy.