2001 Conference Proceedings

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AAC And Developmental Apraxia Of Speech

Cynthia Cottier, M.A., M.Ed., C.C.C.
Augmentative Communication Therapies
(626) 351-5402

Children with developmental apraxia of speech demonstrate severe communication difficulties which certainly negatively impacts their ability to reliably convey their needs, wants and thoughts. The term "developmental apraxia of speech" is often used to refer to children with articulation errors and who also have difficulty with volitional or imitative production of speech sounds and sequences. Clearly, these children are often candidates for augmentative communication system either as a primary communication system or a secondary communication system.

Often, parents of children with developmental apraxia of speech voice concerns as to whether the provision of AAC systems or techniques will inhibit or prevent the continued development of speech. There have been previous studies which have provided evidence that these concerns are unnecessary. The results indicated that when children with developmental apraxia of speech are provided with communication displays during activities that the presence of AAC does not inhibit their speech production. Clearly, an augmentative communication display can provide the child with a reliable means of communication until the child is able to develop his/her own speech skills to a level where they are able to support intelligible speech. If, however, intelligible speech does not develop to this level, the AAC system may certainly then become a more primary means of communication.

This paper focuses on the case studies of three children who were medically diagnosed with developmental apraxia of speech and who had intervention plans developed for them which included the use of AAC devices in addition to more traditional therapy aimed at increasing their speech skills. All three of these children exhibited speech which was informally judged to be less than 30% intelligible to unfamiliar listeners and no more than 50% intelligible to familiar listeners such as their families. AAC systems and techniques were a significant component in the intervention plan for all three of these children.

Each of the three children also demonstrated evidence of significant language delays prior to the initiation of intervention. Theoretically, at least to some extent, the language delays of these children may be attributed to the child's inability to produce and practice language. Since these children were all under 5 years of age, it was critical that AAC techniques and strategies be an integral part of the intervention plan to facilitate continued language development while their oral motor abilities also improved through intervention. Furthermore, it was crucial to preserve the motivation these children possessed for communication by preventing frequent communication breakdowns which were likely to occur if AAC techniques were not included.

The following case studies are examples of positive outcomes of intervention plans which occurred when AAC systems and techniques were included. While all of the children have not as yet developed their oral motor abilities to the point where they are able to consistently support verbal communication, all have exhibited significant improvements in their language level when AAC techniques were applied.

Case Study #1 - A.B.

When intervention began, A. B. was a 3 year, 2 month old boy with a diagnosis of developmental apraxia of speech but cognition was judged to be within normal limits. He demonstrated an intent to communicate and participate in social interactions. He relied primarily on signs, gestures, gross gesturing/pointing, word approximations, facial expressions, and yes/no responses through head nods and shakes. However, A. B.’s ability to communicate verbally to individuals less familiar with him was significantly reduced (i.e., less than 30%). His receptive language abilities were at, or above, his chronological age level and significantly higher than his expressive abilities as he typically used only single word attempts. It was reported that A. B. received specific oral motor therapy to increase oral motor abilities. Clearly, use of an augmentative communication device would improve A. B.’s communication opportunities and abilities while his ability to communicate verbally developed to a level which was reliable.

Initially, A. B. was presented with a light tech picture communication book containing categories of pages (i.e., colors, shapes, toys, animals), and a digitized voice output device (i.e., an AlphaTalker with a 32 location overlay that contained 16 symbols). He quickly and independently used both systems to respond to questions such as "What is your favorite color?" or "What do you want to play with?" using the picture communication book.

In addition, A. B. soon began independently initiate the use of the AlphaTalker to participate in interactive play activities to make choices and indicate preferences as well as to communicate his needs (e.g., he independently retrieved the message "I have to go to the bathroom" which was reportedly the first time he ever spontaneously indicated this need). Almost immediately, A. B. began to initiate the appropriate use of the device and he was significantly more involved and animated when provided with the device.

Within a short period of time, A. B. demonstrated good recall of the symbols and corresponding messages on voice output communication devices and rapidly increased his communication abilities and expressive language skills when using the augmentative communication systems and in addition exhibited increased interaction abilities. Secondary to A. B.'s rapid rate of learning and use of the presented symbols and messages, additional symbols were quickly added to the device overlay until it contained 25 symbols.

In addition, it was clear that A. B.'s expressive language use was significantly higher when augmentative communication methods than when no system was available. A. B. typically did not speak until directed to do so when using only verbal language and then used only single words however, when augmentative communication systems were used, A. B. consistently put together 2-3 programmed words/messages/utterances such as "go" + "more" and "No way Jose" + "my turn".

Based on A. B.'s skill when using augmentative communication systems, his anticipated communication needs, and the large gap between receptive and expressive language abilities, it soon became clear that a digitized voice output device would be too limited for A. B.'s long term use. It was obvious that A. B. showed excellent potential to combine single words to create novel language. Therefore, a DynaMyte communication device was presented to A. B. on a trial basis secondary to device portability features and the language capabilities the device offered. Within two therapy sessions, A. B. demonstrated excellent potential for the use of the DynaMyte and independently initiated the use of this device to convey complex thoughts.

Within 6 months, A. B.'s speech imitation skills had increased significantly. Clearly, marked increases continued to be noted in speech and language skills and soon, minimal differences were noted when he was imitating verbal models or the voice output from a communication device, although A. B.'s volume remained reduced and he needed encouragement to “use his words”. However, when cued to do so, he was able to produce words to reliably convey his thoughts and ideas.

Currently, A. B.’s primary mode of expression is speech; verbal utterances are typically 3-5 words in length. Reduced volume, articulation, oral motor skills, and voice intonation and prosody continue to negatively impact intelligibility and clearly require continued intervention to improve these skills.

Conversations with A. B.’s teacher have revealed that though speech and language skills are still slightly delayed, A. B. is now expressing himself verbally in the classroom.

Case Study # 2 - A. G.

A. G. is now 7 years 1 months of age but was 4 years 6 months when intervention began. A. G. has a diagnosis of autism and apraxia. Initially, A. G. demonstrated an intent to communicate but used only a few gross approximations of overlearned simple signs for communication purposes (approximately 20 in all). Generally, A. G. communicated her needs and wants by using a few word approximations (10), pointing, her limited signs, yes/no responses and taking an adult to what she wanted. Overall intelligibility and effectiveness of speech was less than 20%. In addition, A. G.'s pragmatic use of language appeared to be deviant since she frequently used learned responses rather than manipulating the words and their order to express different meanings.

Initially, A. G. was provided with a Picture Exchange Communication System (PECS) for use at home and at school. Over the course of approximately 9 months, A. G. developed her ability to spontaneously use her PECS system to the Phase V (i.e., responding to questions) and beginning Phase VI level (i.e., responding and spontaneous commenting). During structured therapy activities, A. G. was able to construct 4-6 words symbol sentences to not only request and respond to questions but also to comment, describe and direct.

After approximately 18-24 months in intervention, A. G.'s ability to combine linguistic units (i.e., symbols/words) increased to the level where the actual use of PECS began to restrict, rather than enhance, her communication attempts secondary to the amount of time and energy required to combine symbols to form a 4-6 word sentence. Therefore, A. G. was provided with the opportunity to use a dedicated voice output augmentative communication device (i.e., DynaMyte) during home/clinic based sessions. The clinician felt it was necessary to begin training the use of a more sophisticated augmentative communication device to provide A. G. with enough flexibility to allow for enough generative language capability to allow her to continue to develop her fundamental language abilities. A. G. has responded extremely well to the use of this device in a short period of time (i.e., approximately 6 months) and she has easily applied the skills she developed while using PECS to the DynaMyte.

To date, A. G. is able to not only use the DynaMyte to use complete messages which have been programmed into the device to convey information but also combines single words from between 1 to 3 dynamically linked pages to form novel messages. Furthermore, A. G. is quite capable of navigating through linked pages and accessing information on the dictionary page through the use of categories when necessary. Clearly, A. G. has demonstrated significant improvement in both expressive and receptive communication. In addition, the length and complexity of her verbal utterances, as well as the intelligibility of her utterances, have all increased although her speech intelligibility is still not sufficient to support reliable verbal communication.

Case Study #3 - L. H.

L. H. was 3 year 8 months when intervention was initiated and is now 6 year 7 months of age. L. H. exhibited hypotonia, apraxia and developmental delays. L. H. was an energetic little boy who was quite captivating and engaging. He was able to attend to a variety of tasks which were interesting and motivating for up to 60 minutes but could be distractible as well. L. H. demonstrated an intent to communicate and used single sound approximations of few words (less than 30) for communication purposes. Generally, L. H. communicated his needs and wants by using these single sound vocalizations, gestures, pointing, and getting what he wanted himself. L. H.'s intelligibility was informally judged to be approximately 20% however, this was highly dependent on the listener's familiarity with L. H. and their ability to anticipate what he might desire. Generally, L. H. did no persist when he was not understood. Unfortunately, his communication deficits caused many individuals to perceive L. H. as less capable than his true abilities.

Initially, intervention focused on developing a functional communication method for L. H. as well as to increase his receptive and expressive language abilities. To achieve these goals, a Picture Exchange Communication System (PECS) was provided. The use of his PECS system was intended to promote more functional expressive language abilities while L. H.'s verbal abilities improved to the point where they were sufficient to support reliable verbal communication. Clearly, use of the PECS system decreased the amount of physical effort required for L. H. to communicate and this in turn increased his interest in communicating and ultimately promoted an increase in his production of speech attempts.

L. H. made excellent and rapid progress in the use of the PECS system. In addition, he demonstrated a significant increase in the amount, variety, length and the clarity of his productions. In addition, he frequently initiated the use of his PECS system and paired this with his speech productions. The PECS system clearly appeared to generate increased interest in the communication process. Within 24 months of intervention, L. H. began to use his PECS system to construct symbol sentence consisting of between 4-7 words to not only request but to respond to questions, direct others, question, comment, and describe. In addition, L. H.'s use of verbal utterances to respond to questions and to comment with up to 3 words increased to the 80% accuracy level. Currently, L. H.’s primary mode of expression is speech and he no longer depends on his use of an alternate means of communication as his primary means of communication.


A primary concern of many parents when AAC techniques and strategies are recommended is that it will prevent their child from developing his/her speech skills to the maximum potential. The successful outcomes of the three children with developmental apraxia of speech presented in this paper appears to provide some evidence that the presence of AAC does not limit the development of speech skills. Clearly, including the use of AAC as a major focus when developing an intervention plan was a significant component to the successful outcomes of these children.


Blackstone, S. (1989). Individuals with developmental apraxia of speech (DAS). Augmentative Communication New, 2(3), 3-5.

Beukelman, D., & Mirenda, P. (1998). Augmentative and alternative communication: Management of severe communication disorders in children and adults. Second Edition. Baltimore: Paul H. Brookes Publishing Co.

Blockberger, S., & Kamp, L. (1990). The use of voice output communication aids (VOCAS) by ambulatory children. Augmentative and Alternative Communication, 6, 127-128.

Haynes, S. (1985). Developmental apraxia of speech: Symptoms and treatment. In D. F. Johns (Ed.), Clinical management of neurogenic communicative disorders (pp. 259-266).

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