Childhood Apraxia of Speech (CAS) – Yaelcenter report​

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This paper is a summary of over 20 years of experiencing CAS through treatment, consultation, training and research. Over the years we have worked with over 2000 children diagnosed which speech deficit, in Israel and worldwide. A complex therapeutic system was established, gaining extensive knowledge regarding CAS. Many therapists around world took part in the evolvement of this entity called the VML (Verbal Motor Learning) method.

This paper represents the line of thinking and therapeutic perception of CAS in Yaelcenter. It is based on the extensive experience, local research, literature, and inter-disciplinary approach. This paper analyses the CAS using interdisciplinary tools. The process is not bound to any professional frame or method, but rather allow room to variety of opinions and perceptions.

The goal of this paper is to reflect on the many facets of the CAS phenomenon; diagnosis, evaluation, sources, consequences and therapy. You are invited to draw your own conclusions based on the data presented here.

Mrs Dyspraxia and me

Before diving into the professional literature, it is important to listen first to the personal story of a person who can describe the phenomenon in-vivo. This is a good way to start understanding the phenomenon. A 5 years old boy diagnosed with ASD, came to an evaluation in Yaelcenter. He was non-verbal, no pre verbal skills and not even single syllables production. There were severe hypotonia while the examination suspected severe CAS. He looked very bright though having no expressive skills. The speech difficulties were extremely severe, this is how he described it through a presentation he wrote for a conference when he was 9 years old:

“….Dyspraxia is difficulty with planning a movement. Therefore, I don’t have problems in school or romance, but it is difficult for me to talk or getting dressed. The biggest problem with being dyspraxic is that people think you do everything on purpose, because how come you are not going up the slide when told to do so. I mean, once it works and once not, it is all about divine inspiration or the organizing your legs ‘ the boy doesn’t have learning skills’. When they tell you to go to the grocery store to buy icy poll with your aide and you are shouting and crying ‘he likes icy poll, so he probably doesn’t understand’. “

“…if you don’t suffer from dyspraxia you can’t really understand it. When I was few months old, I tried to say mummy, but it didn’t come out. I wanted to move my tongue, but it curved backwards. I wanted to cry, don’t remember exactly what I was thinking but I felt depressed. I have tried to speak many times more but instead of speech sounds I was growling, I felt cursed. No one understood what I was trying to say. My solution was sophisticated politics. I made everybody work by being passive. I wanted to revenge at who ever thought I didn’t want to talk.”

(Translated from Hebrew).

Today this boy is 18 years old, graduating bachelor’s degree in art history and public law. He is an artist, painter, writer and publicist. Yet speech is not intact.

A poem that he wrote represents the inner perception of a child straggles with CAS: (translated from Hebrew)


The other place where I stand,
Isolated like an island in the middle of the sea
In the other place I learn
That I am not like everyone else
In this other place the silence is ruling
The voice is not coming, in or out
The sea is built from millions of tears
And the island is island of love
I long for a comforting hug
Saying: your life is not a sin
I will cry for what I have taken from you
You answer: you know also how to give back
The difference is forged in me, engraved and sad
This is how I was born.
There is no shame
But when I am hugged and loved
I know that I have reached the land

In order to understand Apraxia and CAS specifically, it is not enough to define or observe, we need to feel the essence of the difficulty. If you want to experience Apraxia try to perform a very difficult motor task such as; gaggling with 3-5 balls, bouncing table tennis ball on the side of the racket or throwing darts accurately 50 times consecutively. Practice consecutively for 30 minutes in front of an audience and examine your feeling. It is very likely that you would like to stop after less then a minute. Speech is a much more complicated skill and highly more important than the skills mentioned above. Therefore, inability to acquire speech might have much bigger consequences. The non-verbal child is experiencing this frustration for years.


The semantic meaning of Apraxia/Dyspraxia in Latin is; A= total absence, Dys = partial absence, Praxis = planning of movement. Apraxia is a motor disorder caused by damage to the brain (specifically the posterior parietal cortex) in which the individual has difficulty with the motor planning to perform tasks or movements when asked, provided that the request or command is understood, and the individual is willing to perform the task. Apraxia can occur in different body parts, areas or functions. The Apraxia can be acquired or developmental, it can be mild or severe. Using this term is subjective depended on the country, profession and organization. In some countries Dyspraxia is the leading term while in others Apraxia. In other places Apraxia is considered as the severe version while Dyspraxia the mild version of the phenomenon. Eventually the important factor dealing with Apraxia is the essence of the phenomenon regardless of the arbitrary names given.

American speech, Language and Audiology Association (ASHA) definition

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.
(ASHA CAS report , 2007)

DSM 5 definition

The Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (American Psychiatric Association [APA], 2013) uses the term verbal dyspraxia to describe this disorder. It is discussed within the Speech Sound Disorders category, under the subheading, “Associated Features Supporting Diagnosis.” Verbal dyspraxia is described in the DSM-5 as a disorder in which “other areas of motor coordination may be impaired as in developmental coordination disorder” (p. 44). According to the DSM-5 (2013:44) Verbal Dyspraxia is a term used for speech production problems and is included in the DSM-5 Communication Disorders section as “Speech Sound Disorder”. DVD is essentially an expressive language disorder where it may be difficult to understand what the student is trying to say. In severe cases the student’s speech may be unintelligible. The student with DVD frequently struggles to produce words or sounds, and facial distortions may accompany his/her struggle to produce targeted sounds. The student may have a limited range of consonant and vowel sounds. Speech may be slow and lacking in normal phrasing and intonation, and as a result the student’s speech may sound very flat and what he/she is communicating may not sound very interesting, with the result that the student may not communicate what was intended.

Diagnostic criteria for “Speech Sound Disorder” (DSM-5, 2013:44)

  1. Persistent difficulty with speech sound production that interferes with speech intelligibility or prevents verbal communication of messages.
  2. The disturbance causes limitations in effective communication that interfere in social communication, academic achievement or occupational performance, individually or in any combination.
  3. Onset of symptoms is in the early developmental period.
  4. The difficulties are not attributable to congenital or acquired conditions, such as Cerebral Palsy, cleft palate, deafness or hearing loss, traumatic brain injury or other medical or neurological conditions.

Speech Disorders Classification System (SDCS)

Shriberg (2010a) describes the speech disorders classification system (SDCS) which organizes the speech sounds disorders and define them. Shriberg divides the disorders into 3 sections:

  1. Speech Delay (SD) includes 3- to 9-year-old children with significant speech sound deletions and substitutions that typically normalize with treatment.
  2. Motor Speech Disorder (MSD), includes children with significant speech sound deletions, substitutions, and distortions that may not completely normalize with treatment. This section includes Apraxia and speech and dysarthria (tone deficit).
  3. Speech Errors (SE) includes speakers with speech sound distortion errors (typically on sibilants and/or liquids) that are not associated with the risk domains and adverse social, academic, and vocational consequences documented for SD and MSD, but may also persist throughout the lifespan.

The SDCS was found reliable (Shriberg et al, 2010b). SDCS presents a good effort in trying to understand and classify the speech sound disorders.

However, there are few difficulties with this classification:

  1. The definitions of SD and MSD are partially differentiated by the treatment outcomes – being or not being normalized by treatment. Using observed treatment outcomes can’t serve as a major differential factor but rather the essence of the phenomenon. Differentiating SD from MSD should be done based on the existence of a motor component as a source of the problem.
  2. Shriberg defines SD at age range of 3-9 years old based on the criteria “that typically normalize with treatment”. Shriberg defines three etiologic subtypes of SD : (a) cognitive-linguistic processing constraints that may be, in part, genetically transmitted (SD-GEN); (b) auditory-perceptual processing constraints that are the consequence of the fluctuant conductive hearing loss associated with early recurrent otitis media with effusion (SD-OME); and (c) affective, temperamental processing constraints associated with developmental psychosocial involvement (SD-DPI). What if the cause for the SD is poor motor planning? What if the SD normalized through treatment is motor based? Using the terms SD and MSD at the same level of definition is problematic. One is defined using the behavior of phenomenon (SD – the speech is delayed) while the other by using the cause (MSD – motor speech deficit). Even though Shriberg do mention 3 possible causes for SD, the main definition is based on age range and success in treatment.
  3. The reliability test for SDCS (Shriberg et al, 2010) goal was to estimate the reliability of the three data reduction methods used in the SDCS: narrow phonetic transcription, prosody-voice coding, and acoustic analyses. This test was based on 5 MSD participants who had very specific genetic diagnosis and were verbal. These participants don’t represent the MSD population, in addition to the very small sample size. The results should be carefully analyzed due to many limitations.
  4. The SDCS is relaying on ASHA CAS diagnostic guidelines which refer mostly to children with verbal skills. Following these guidelines exclude the non-verbal children which should be included, if the main source of their speech deficit is motor based. Further discussion regarding the guidelines in the following pages.

The SDCS classifies the speech disorders, however some difficulties are founded in the basic definitions. I would suggest the following corrections:

  1. Speech delay should be a broad name for all speech deficits since speech is delayed in all cases.
  2. The deficits should be differentiated by the cause category and not by the behavior of the treatment.
  3. The time frame should not be relevant for the definition since the cause might have existed from birth, and still relevant after 9 years of age.
  4. The influence of the cause should be classified according to severity.

Diagnostic evaluation of motor speech skills (DEMSS)

Strand et al (2013) developed a diagnostic tool for CAS to assist in the differential diagnosis of CAS. The research protocol was very complex and thorough, however lacked in subject’s definition and inclusion criteria:

1. The DEMSS claims to address severe CAS “the DEMMS is designed specifically to examine the speech movements of younger children and/or children who are more severely impaired, even those who may not yet produce many sounds, syllables, or words.” However, it will not include non-verbal children. The DEMSS treats children with partial verbal skill as severely impaired.
2. children diagnosed with ASD were excluded from the study as if there is no CAS within ASD. This exclusion criteria potentially dismissed big CAS population with very specific features.
3. Participants needed to be able to attend to the clinician for the duration of the DEMSS, attempt the direct imitation, and tolerate cueing. These criteria might create bias as well in the final results of the study.
4. The cluster analysis failed to identify CAS based on clinical diagnosis.
5. The clinical diagnosis was the gold standard for the test validity. Using the subjective guidelines, whom the test strive to prove, as the gold standard for the test is problematic.

CAS Characters

The main guidelines for diagnosis CAS by ASHA (2007) are:

1. inconsistent errors on consonants and vowels in repeated productions of syllables or words.
2. lengthened and disrupted coarticulatory transitions between sounds and syllables.
3. inappropriate prosody, especially in the realization of lexical or phrasal stress.

Children diagnosed with CAS have demonstrated few acoustic characters:

  1. Decreased differentiation of stop place of articulation (Sussman,Marquardt, & Doyle, 2000),
  2. Decreased differentiation of vowels (Nijland et al., 2002),
  3. Higher degrees of anticipatory coarticulation within syllables (Maassen et al., 2001; Nijland, Maassen, van der Meulen, et al., 2003),
  4. Lack of impact of syllable boundaries or syllable shape on coarticulation (Maassen et al., 2001; Nijland, Maassen, van der Meulen et al., 2003),
  5. Lack of intersyllabic coarticulation (Nijland et al., 2002), and variable idiosyncratic patterns that were less predictable acoustically in any given phonetic context (Maassen et al., 2001).
  6. Nijland, Maassen, van der Meulen, et al. (2003) further noted that children with CAS had higher scores than typically developing children on measures of coarticulation and vowel accuracy when a bite block was placed between their teeth.

Few studies have addressed the hypothesis that children suspected to have CAS have deficits in auditory perception, auditory discrimination, and/or auditory memory; Bridgeman and Snowling (1988), Groenen and Maassen (1996), Maassen et al. (2003).

Summary definition

There is no consensus regarding the definition of CAS in the literature. Most of the guidelines come from ASHA, however visiting other countries reveals different perceptions. Since there is no biological gold standard for CAS, the diagnosis relays on the subjective guidelines which are not under agreement. This situation leads to difficulties in the validity of research protocols.

Beyond the difficulties in defining the CAS group, the current guidelines seem to exclude a very big group of CAS children. We can find in the literature the claim that there is no relation between ASD and CAS, hence the speech deficits in ASD are not motor related (will be discussed in a separate paragraph). In addition, the guidelines refer to children with some speech skills, hence verbal. These guidelines exclude the non-verbal population and the ASD population from CAS. These two groups overlap since many of the ASD population are non-verbal. Even so, the precentage of children excluded from the definition is extremely high.

This definition demonstrates the ruling professional opinion of what is it CAS. It is based on symptoms rather then the essence of the phenomenon, hence fails to include large groups of children. The major inclusion criteria for CAS should be the existence of motor planning deficit of speech and not the symptoms accompanied. The research efforts should be focused on defining the representing factors of motor speech deficit.

CAS Diagnosis

The diagnosis of CAS is based on the definitions described earlier. In order to diagnose CAS the clinician can use a diagnostic tool such as DEMSS or follow the guidelines prescribed by ASHA. In the VML method we use a different procedure. The first step would be to run a differential diagnosis. The examiner will screen the possible causes for non-speech condition and eliminate the irrelevant ones:

1. Anatomic disorder – soft palate insufficiency, damaged tissue, mouth structure, Etc.
2. Hearing
3. Mutism
4. communication
5. Dysarthria
6. Vocal cord damage
7. Local paralysis
8. Severe hypotonia
9. Expressive Language disorder/Aphasia
10. Muscle degenerative disorder
11. Breathing problems
12. Verbal Apraxia
13. Speech delay
14. Metabolic disorder
15. Cognitive
16. Other

After excluding the irrelevant options, the examiner needs to decide between 2-3 options usually. If CAS is one of the options, then it is required to examine the deficit thoroughly.


1. Eliminate all the measurable causes
2. Look for neurological signs and symptoms
3. Look at imitation skills
4. Look at general motor capabilities
5. Look at pre-verbal skills
6. Look at Single syllable pronunciation
7. Look at multi-syllabic structures control

Running this procedure ensures screening all the primary numbers of speech. This test can estimate with high resolution the occurrence of a speech motor deficit.

CAS insights


CAS prevalence is hard to determine due to the lack of reliable diagnosis. Very few prevalence papers were published in the professional literature:

  • 3.4-4.3% of the children with speech delay Delaney & Kent, 2004
  • Estimation of 1-2 / 1000 children Shriberg, Aram, & Kwiatkowski, 1997a
  • Group of children with communication problems was sent to non depended, blind ASD and CAS tests. The results showed that 63.6% of ASD have CAS (Tierney et al, 2015)

Tierney study was the only one who tested the question directly, even though only with relation to ASD and with small sample size. The high percentage of occurrence of CAS within ASD suggests high potential CAS prevalence of at least 1/100.

Autism and CAS

There is no consensus regarding the comorbidity of ASD and CAS.

There are researches who claim that the interaction between the two phenomena is very weak.

Shriberg (2011) found that there is no relation, however the research methodology was questionable. The research used convenient sample of 46 children with ASD participating in another research. The criteria for the other research was good intelligibility, hence all the children were verbal with good intelligibility. The chances of finding in this specific group children with CAS were very low to begin with, therefore biased research and results should be ignored..

The DEMSS tool developed by Mayo clinic (Strand et al, 2013) didn’t include children with ASD in the research, assuming there is no CAS among ASD.

Tierney et al (2015) on the other hand found a very strong relationship between ASD and CAS in a blind study. The definitions of CAS, including mostly verbal children, excludes the non-verbal population from the diagnosis among them many diagnosed with ASD.

In our clinic we see very strong relation between ASD and CAS. Most of the children referring to Yaelcenter clinic have speech deficit. In a 6 years longitudinal study done in Yaelcenter we found that over 65% of the children attending the clinic are diagnosed with ASD.

Inspecting their speech deficit will put most of them within CAS range having motor speech deficit. This finding can’t show direction in interaction between the phenomena but certainly a very strong connection.

Speech vs Language

The use of verbal language is a skill combined of few basic skills; understanding of language, pronunciation, expressive language and basic communication skills. The pronunciation is the ability to intentionally produce the speech sounds to create a meaningful language phrases. This skill is motor based, having sensory aspects such as; hearing, proprioception and tactile. The expressive language skill includes few domains: syntax, morphology, semantic and cognitive. All domains interact to produce one outcome; however, each domain stands for itself. We can see the unique neurological patterns of each domain through neurological pathologies. In these cases, we can observe a unique damage to a specific system while the others are intact. In order to use verbal expressive language, the person must have speech skill. Verbal expressive language can’t be tested reliably without speech. We need to distinguish these two systems even though the pathological outcome for both might manifest the same result. CAS is motor based deficit therefore doesn’t represent language deficit.

Developmental Consequences of CAS

1. Emotional – there are usually severe emotional influences for CAS, especially for non-verbal children. We can observe low self-confidence, low self-perception, frustration and behavioral problems.
2. Language development – inability to talk or some deficit in intelligibility can lead to reduced social participation, reduced interaction and delay in language development. It is not true for all cases – some will develop very rich language without speech skill at all.
3. Social – speech is the strongest and most common communication tool used in social context. Inability to speak usually reduce social interaction and the acquiring of social skills.
4. Communication – since speech is the most common communication tool, lack of it might lead to reduced communication and restricted interactions, especially in early age. Even when there is typing or writing skills, which can express full language range, the speech skill is a priority.
5. Cognitive development – reduced interaction and social participation due to speech deficit might lead to reduced participation in cognitive tasks and learning. The reduced use of language, which is part of cognition, can lead to a delay in cognitive development. Stereotypic notion says that if one can’t talk then there is no understanding. It is easy to conclude of cognitive skill based on speech level. However, cognition can develop without speech to the highest levels, and we should not determine the cognitive bar by the speech limit.
6. Lack of common knowledge – low participation, special schools and stereotype thinking might lead to decreased learning and low world knowledge.
7. False diagnosis – especially with non-verbal children due to CAS, a false diagnosis of ASD is very common. In a longitudinal study done in Yaelcenter only 5% of the children with severe speech problem (average age – 6 yrs) were diagnosed with CAS. Most of them were diagnosed with ASD. The meaning of it is wrong intervention based solely on communication tools rather then motor tools in addition.
8. Lack of appropriate educational frame – CAS phenomenon has no unique educational status or specific educational frame as ASD for example. These children will be placed in ASD, or language based frames, which will not necessarily address their unique needs.

CAS evaluation

Here is a list of few CAS evaluations:

1. The VML method evaluation process ( )
2. the Screening Test for Developmental Apraxia of Speech (Blakeley,1980)
3. The Tasks for Assessing Motor Speech Programming Capacity (Wertz, LaPointe & Rosenbeck, 1984).
4. DEMSS- Mayo clinic – Strand, E. A., McCauley, R. J., Weigand, S. D., Stoeckel, R. E., & Baas, B. S. (2013). A motor speech assessment for children with severe speech disorders: Reliability and validity evidence. Journal of Speech, Language, and Hearing Research, 56(2), 505-520.
5. Nonspeech test – Huer, 1983.
6. PROMPT evaluation
7. Goldman Fristoe Test of Articulation (GFTA-2) (Goldman and Fristoe, 2000).
8. REST test
9. The Kaufman Speech Praxis Test for Children
10. Nuffield test –
11. Apraxia Profile
12. Khan Lewis Phonological Analysis 2
13. Arizona Artic Prof Scale 3
14. Photo Articulation Test 3 (PAT3)
15. CAAP – Clinical Assessment of Artic & Phonology
16. Test of Phonological Awareness Skills
17. Linguisystems Articulation Test (LAT)

CAS Treatment

Specificity of the CAS treatment Due to the complexity of the CAS phenomenon which includes many areas of knowledge, the optimal intervention would be multi facets as well. Here are specific guidelines for treating CAS:

1. Intensity – since the main problem is motor planning, intensity of practice is required. It is very difficult to learn a novel, complex, motor task with minimal repetition and without intensity. Speech as a motor skill is very complex hence required intense practice.
2. Consistency – one of the common characters of CAS is inconsistency. The consistent training is important to create stability and sequence in learning, and to overcome the inconsistency which characterizes the phenomenon.
3. Faith – acquiring the speech skills for the apraxic child can be very difficult task. An important and powerful tool to deal with the extreme difficulty is faith. Faith of the child in the process and faith of the therapist in the child.
4. Motivation – extreme developmental obstacle requires extreme motivation source. At the first stages there are many failures and disappointments. In order to overcome that we need to supply enough motivation for the child. We need to allocate motivation sources and manage them along the treatment process. Without motivation there is no treatment.
5. Precision and accuracy – due to the complexity of the speech task we are required to achieve high precision and high accuracy within the treatment process. Sometimes a slight change in the direction of movement can be the difference between producing a sound or not. There are hundreds of variables to control simultaneously with good accuracy and precision.
6. Creativity – in the first stages of treatment the improvement is slow or even doesn’t exist. Despite that, we need to continue with the same topics of intervention. In order to maintain motivation and participation, the therapist must be very creative. The therapist needs to create small changes in practice constantly to keep the child motivated and interested.
7. Sensitivity – inability to speak might have severe emotional consequences. The therapist needto be very sensitive to the child’s emotional state and nonverbal massages in order to keep the child a positive state of mind. There are few techniques and guidelines which help the therapist maintaining happiness.
8. Multi-dimensional intervention – This type of intervention is essential in CAS case since the phenomenon is combined of many developmental areas. The multi-dimensional intervention can include several therapists from different areas or a multi-dimensional therapist.
9. Motor Learning Principles – since CAS is motor based it is necessary to use motor tools in treatment. MLP are tools used in movement teaching in different areas. These tools should be used for speech treatment as well.

Intervention Methods

There are few intervention methods for CAS across the world. Some are more specific, and some are in general speech therapy use:

The VML method

The VML method is a treatment system targeting motor speech disorder and specifically Apraxia of speech in children and adults. The VML method was developed in Israel, by Dr Elad Vashdi, through clinical experiences with children with Apraxia of speech, since 1997. The VML system is part of a bigger therapeutic system called MDT (Multi-dimensional therapy) and represents the interdisciplinary approach in therapy. The VML method includes a unique evaluation tool, mathematical analysis process, hundreds of manual techniques, extensive use of MLP and specific use of unique teaching principles. Few articles were published supporting the system, (Vashdi, 2013, 2014, Bell, 2017). The VML method is being practiced around the world in several languages and offers online evaluation and training. More details can be found at https://train.yaelcenter.con and

The PROMPT method

PROMPT, an acronym for PROMPTS for Restructuring Oral Muscular Phonetic Targets, is a multidimensional approach to speech production disorders has come to embrace not only the well-known physical-sensory aspects of motor performance, but also its cognitive-linguistic and social-emotional aspects.

Kaufman method

The Kaufman Speech to Language Protocol (K-SLP) is a method of teaching children with apraxia of speech the easiest way of saying words until they have increased motor-speech coordination. The Kaufman Speech to Language Protocol teaches the shell of words, without including the complex consonants, vowels, or syllables which make a word too difficult for the child to attempt. This teaching method is a reflection of how young children produce “first words” (Gomez et al, 2018).

ABA (Applied behavior Analysis)

The ABA method is one of the most popular methods for ASD in the world. The ABA is a behavioral approach which treats speech as a behavior and tries to modify it. ABA Therapists deal with CAS within ASD frequently.

OPT (Oral Placement Therapy)

The OPT method is SLP based and deals mostly with feeding, swallowing and speech difficulties. The method is motor based while using many oral exercises in treatment. This method is part of Talk Tools project which developed a tools kit for oral treatment.

Nuffield program

The Nuffield Dyspraxia Program (NDP3® Complete) is a flexible, comprehensive assessment and therapy resource for the management of severe speech disorders. NDP3® is used by thousands of speech and language professionals around the world and comprises an extensive treatment package, including therapy principles and techniques and a large set of images, worksheets and activities. (Murray, 2015).

REST program

Rapid Syllable Transition Treatment (ReST) Program. Rapid syllable transition treatment (ReST) is an evidence-based treatment approach for children with Childhood apraxia of speech (CAS). ReST uniquely uses non-words (e.g. kuba, deefa) to teach transitions between sounds and syllables and to improve prosody. (Murray, 2015).

Melodic intonation

Melodic Intonation Therapy (MIT) is a language production therapy for severely non-fluent aphasic patients using melodic intoning and rhythm to restore language. Although many studies have reported its beneficial effects on language production, randomized controlled trials (RCT) examining the efficacy of MIT are rare. (Slavin & Fabus, 2018).

Linguistic Approach

claims that the need for social communication and language will encourage speech development among children diagnosed with CAS. The linguistic approach will use mainly Augmentative and alternative communication tools while practicing language. It will encourage language through creating language supported environment. This approach doesn’t explore the motor speech needs but rather put language constraints.

SLP (Speech Language Pathologist)

this is the primary profession which deals with speech, language, auditory and communication deficits. Speech treatment is the core of the profession. Unlike the described methods, SLP is a profession which uses different methods. Most of the research regarding speech originate from the SLP profession.

Augmentative and alternative communication (AAC)

The main purpose of the non-verbal child treatment is to enable good communication tool. The best tool is speech, however, any communication tool which can help should be applied as well. Training speech is usually a long process which can take years sometimes. Usually there will be other communication tools easier to acquire which can serve the communication purpose. AAC tools might include sign language, pictures exchange, writing/typing, or gestures. Other tools for children with severe somatic disorder might be eye tracking device ( or brain wave reader (Wolpaw, & McFarland, 1997). The most common AAC is communication through pictures exchange. There are many methods implementing this type of communication; tablet apps (Jabtalk, Grid, touch chat etc), Andy Bondy system ( and others. AAC can’t replace speech but rather serves as temporary solution. However,in some cases, it is the only solution.

Non speech oral motor exercises (NSOME)

The use of Non speech Oral Motor Exercises (NSOME) for motor speech sounds disorder treatment has been discussed in the literature in the last three decades, with most of the research presenting in conclusive results for using NSOME. Few researchers argued with passion that using NSOME is not ethical and therapists should “look themselves in mirror” and ask whether they are using an evidence-based practice and consider their morality and integrity (Kimhi, 2008, Lof , 2007). 75% of the academic instructors examined in a study conducted in the United States didn’t teach NSOME in their classes (Lof & Watson, 2009). Even though not taught in the academic settings, and the literature “forbids” it, many clinicians still use the NSOME. Few studies (Muttiah, 2008; Muttiah, Georges & Brackenbury, 2011) have discussed the differences between the clinicians and the researchers on the matter. The continuing use of NSOME in the therapeutic field may result from an old fashioned attitude (Kamhi, 2008) or from other misconceptions (Lof , 2007) that contradict what is taught by researchers. On the other hand, the use of these exercises in the field can result from an unsolved theoretical issue, as it is likely that practitioners are using a tool that works for them, while research has yet to support this. The relationship between NSOME and speech production should be researched more thoroughly in order to present a possible answer to the above debate.

In Yaelcenter institute we have conducted a research to test the connection between NSOME and speech treatment. The purpose of the research was to add evidence related to that debate and show the correlations between NSOME and sound production among children diagnosed with Childhood Apraxia of Speech (CAS). 256 entry evaluations and 89 long term treatment processes were analyzed retrospectively. The correlations between Single Sound Pronunciation (SSP) and NSOME variables (i.e. blowing, oral motor imitation and tongue movements) were calculated using the entry evaluation group, as well as the correlations between the changes in SSP and NSOME variables, using the long-term group. High correlations were found between NSOME variables and SSP in both groups tested. The results confirmed the relationship between oral motor skills and sound production.

Our clinical experience, involving over 2000 cases of children with motor speech disorder, supports the correct use of NSOME in the treatment. NSOME are not the goal but rather the mean to achieve speech goals. In some cases we found it critical for achieving speech sounds and in other cases their contribution was minimal.

Treatment intensity

ASHA (2007) recommended 3-5 treatment sessions per week due to CAS complexity and the need for intensity and repetition. Daily intervention can be very beneficial with periods of non-treatment weeks for resting. It is not easy to find a therapist for so many sessions per week, therefore we would suggest finding other solutions.

The intervention can be delivered by a professional speech therapist, parent, educator or tutor. The intervention should be monitored by the professional expert. Following this way will enable sustaining full program with feasible costs.

The length of the allied health treatment session is usually 20-45 minute depends on profession and place (30 minutes on average). The optimal speech treatment time is questionable. We find speech treatments length of 30-45 minutes as not satisfying the optimal needs of the therapeutic system, therefore we recommend sessions of 60-90 minutes at least. This time frame allows the therapists to have many repetitions and enable distributed practice. It is not easy to have the child focused and participating for 90 minutes, however, with good energy level management it is doable.

It is highly important to train the parents and other intervention providers in the system to participate in the process. This is the role of the professional therapist acting as the axis of the therapeutic system. This training can change the child’s environment and have a crucial effect on the child’s progress. The training should be thorough and intensive. However,not every parent can take this role and not every educator or tutor can practice speech.

Yaelcenter developed an online training tool for treating CAS. The training includes over 80 lessons using various learning platforms, which supply techniques demonstrations, background materials, evaluation ad analysis tools and teaching principles. This training enables therapists and families around the world an easy access to the CAS treatment knowledge.

The training can be found at


This report was conducted by Yaelcenter, hence represents Yaelcenter’s professional perception regarding CAS, using scientific knowledge.

This paper relies on literature evidence and worldwide clinical experience.

This paper reviewed many facets of CAS; diagnosis, evaluation, insights, treatment methods and controversial topics, along with the personal, in-vivo, view of CAS.

The objective was to present CAS on all of its aspects in a clear and organized way, for families and professionals.

The area of CAS is relatively new and limited due to lack of diagnosis, poor professional consensus, low awareness, low financial support and relatively limited treatment options.

On the other hand, the number of children require intervention is growing rapidly. Many of them are not getting the optimal intervention due to false diagnosis.

It is highly important to keep researching CAS theoretically and clinically.

It is important to find the key marker for reliable diagnosis and treatment.

We need to keep investigating and questioning our techniques and therapeutic tools. CAS is a motor planning problem. The main deficit is motor based and not language or communication based. However, it does effects directly the language, communication and social participation. Some research tries to tie CAS to other phenomena in a direct manner.

This research and other notions claim that CAS is also characterized by learning deficits and language problems. The semantic definition of CAS is very clear – motor based and nothing else. There might be comorbidity with other syndromes, but it stands for itself. Therefore, the differential diagnosis is highly important since CAS should be treated with motor tools while considering language and communication influences.

Motor constraints should be the first in line while planning the treatment. CAS definition excludes non-verbal children and the whole ASD field.

The definition and diagnosis guidelines are not essence based but rather symptoms based. This bias narrows the scope of the phenomenon and has huge implication regarding treatment and research.

Most of the entry evaluations at Yaelcenter are of non-verbal children diagnosed with ASD. Most of their speech deficit is motor based, proven in results of treatment years later.

We advise the use of motor speech praxis as the diagnosis marker for CAS regardless of severity, treatment results or other diagnosis.

Due to the complexity of the phenomenon it is highly recommended to use interdisciplinary treatment approach for CAS.

In addition, we believe that a multi-disciplinary therapist (York, Rainforth & Giangreco ,1990) can contribute significantly to this type of program, guided by experts from various fields.

Attributing CAS to a specific profession will yield better results but rather reduce the creativity needed to solve therapeutic cases.

Each practitioner should be tested by how significant the professional contribution is to the system and not by the profession.


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Dr. Elad Vashdi

Dr. Elad Vashdi

Yael Center founder, VML and MDT method inventor, has a doctorate in physiotherapy, published multiple articles in relation to childhood apraxia of speech (CAS), developmental disorders, child development and intellectual disability.

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The Yael Center is a professional therapeutic organization which focuses on speech therapy and multi-dimensional therapy via two unique methods. These methods were developed by the founder of the center, Dr Elad Vashdi, and Yael Center’s members. The center has been in existence since 1996.

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