What We Need to Know About AAC Interventions
May 31, 2022
One of the most significant characteristics of autism spectrum disorder (ASD) is a “delay in, or total lack of, the development of spoken language.” The Centers for Disease Control and Prevention (CDC) report that approximately 40% of autistic children are non-speaking and do not develop sufficient natural speech or writing to meet their daily communication needs. Individuals who are non-speaking qualify for augmentative and alternative communication (AAC) interventions to supplement (“augmentative”) or replace (“alternative”) natural speech.
AAC interventions include unaided strategies, such as gestures, manual signing, and fingerspelling, and aided strategies, such as speech-generating devices, tablet devices (e.g., iPad) with AAC-specific applications, communication boards, and the Picture Exchange Communication System (PECS). The essential goal of AAC interventions is to enable communication and language through any combination of modalities (e.g., remaining natural speech, synthetic/digitized speech output, graphic symbols, manual signs, gestures, body language, etc.).
Many families of non-speaking individuals as well as educators, speech-language pathologists, and occupational therapists, among others, often fear that implementing AAC may prevent the acquisition of natural speech. These concerns seem to be based on the common misconception that the use of an alternative communication modality might lead the individual to rely more and more on those “easier” modalities while giving up on learning natural speech.
The still common terms “severe communication disorder” and “complex communication needs” that are used to refer to a lack of speech and language further stimulate fears about the severity of the condition and imply significant reductions in quality of life. Fortunately, applied research in AAC has shown that such fears are not warranted. A growing body of research has demonstrated the many valuable benefits of AAC intervention:
Moreover, research suggests that AAC does not prevent natural speech but may actually facilitate its development.
Consequently, today there is consensus that AAC interventions benefit a much larger population, including not only those who already present with delays or impairments in speech and language, but also infants and toddlers who are at risk for these conditions. It is commonly understood that AAC interventions for non-speaking individuals should start as soon as the first warning signs appear. Early AAC intervention has the potential to reduce severity levels of language and intellectual impairment, and is often associated with improved long-term intervention outcomes.
In the past, AAC interventions for non-speaking autistic individuals have primarily focused on establishing functional communication and teaching basic communicative abilities such as requesting, labeling, and rejecting. Utterances produced through AAC modalities often remain at the single-word stage. One current challenge for the AAC field is in developing autism-specific interventions that systematically move learners from single word to multiple word utterances. The communicative repertoire needs to be expanded to produce more complex sentences and multi-word utterances. In other words, when introducing AAC to autistic learners, it is critical to have a strong set of instructions that go along with an AAC modality (e.g., manual signs, graphic symbol board, AAC devices). This will enable the learner to understand and build language through these alternative modalities.
Two approaches in particular are currently being investigated and have become increasingly popular for language learning via AAC: language modeling and matrix training. Both have shown strong potential in facilitating language growth during AAC interventions. Language modeling approaches include techniques such as aided language stimulation or aided language modeling. These are based on the notion that the learner can observe and mimic an interventionist using correct symbol utterances and combinations and reproduce these through an AAC modality. Matrix training is an innovative approach for teaching the combination of multiple symbols into full sentences; it also enhances generalization of newly learned language skills. Successful intervention results have been reported for both approaches, yet further replications are necessary to refine intervention protocols and elevate their empirical foundation to the level of an evidence-based practice.
Another challenge is to create meaningful literacy experiences and interventions for non-speaking AAC users on the autism spectrum. Recent research shows that about 90% of non-speaking individuals including those who identify as autistic are not acquiring literacy skills. As language skills keep on growing, it is equally important to enhance early literacy learning at the same time. Many autistic learners show emerging skills in identifying letters and recognizing sight words. Early literacy instruction is important to fully explore this potential.
An engaging and motivating intervention strategy to work towards this goal is shared storybook reading. In the same fashion as their typically developing peers, non-speaking autistic individuals can learn through storytelling and retelling. Such natural activities can enhance thinking and language skills while working towards reading comprehension. Shared storybook reading is strongly connected with later vocabulary acquisition and reading skills. Ultimately, autistic children who use AAC require the same type of experiences and instructions with books as their typically developing verbal peers.
Applied research on AAC interventions for non-speaking autistic individuals is of critical importance to affected families and their service providers because this field is particularly vulnerable to unsubstantiated, pseudoscientific treatments. Examples include facilitated communication and rapid prompting.
Facilitated communication is a non-evidence-based approach to communication intervention wherein a facilitator physically guides the hand or arm of a non-speaking individual to generate messages on a keyboard. The produced messages are claimed to be those of the person being facilitated. Experimental AAC studies, however, have revealed that the messages are produced by the facilitator.
Rapid prompting is a similar treatment option that relies on a facilitator to operate a letter board while the individual follows prompts for pointing, typing, and writing. Although such approaches may be appealing to families due to exaggerated claims about amazing and unprecedented benefits, there is consensus that they are pseudoscientific, unsafe, and unethical. Leading organizations such as the American Speech-Language-Hearing Association, the American Association on Intellectual and Developmental Disabilities, and the International Society for Augmentative and Alternative Communication have published position papers cautioning practitioners about the use of such methods.
AAC interventions for non-speaking autistic children and adults should be grounded in scientific evidence for their effectiveness. It is important to know that many AAC interventions such as the Picture Exchange Communication System or the use of speech-generating devices combined with proper intervention protocols have a solid research base and meet the standards for an evidence-based practice as outlined in reports by the National Autism Project and the National Clearinghouse on Autism Evidence and Practice. These AAC options have been proven to be reliable and beneficial solutions that do not present with the potential harms of pseudoscientific treatments.
When starting to use an AAC intervention with a non-speaking autistic child or young adult, keep the following tips in mind:
If we keep these principles in mind, we can enable our autistic learners to fully explore their communication abilities, maximize the outcomes of AAC interventions, and reach better participation across educational and social environments.
Oliver Wendt, Ph.D., is director of the Potsdam Augmentative and Alternative Communication Research Lab, associate professor and chair of cognitive and emotional disabilities at the University of Potsdam, Germany. He is also a faculty associate with the Purdue Center for Families and the Purdue Department of Educational Studies. His research investigates the efficacy of AAC interventions for individuals with autism and developmental disabilities. He specializes in single-subject experiments and meta-analysis of treatment efficacy research. He is a member of OAR’s Scientific Council. He is also first editor of “Assistive Technology: Principles and Applications for Communication Disorders and Special Education” and associate editor of the Augmentative and Alternative Communication Journal.