American Speech-Language-Hearing Association

Communication Services and Supports for Individuals With Severe Disabilities: FAQs

Basic Information About Augmentative and Alternative Communication

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What is AAC?

AAC stands for "Augmentative and Alternative Communication." AAC is used by people who some of the time or all of the time cannot rely on their speech.  For example, a child who has not yet developed understandable speech might use a speech output device to produce words.  But, as his speech becomes clearer, he may only need to use this device in some situations.

AAC defined: The American Speech-Language-Hearing Association defines AAC as an area of clinical practice that attempts to compensate (either temporarily or permanently) for the impairment and disability patterns of individuals with severe expressive communication disorders (i.e., the severe impairments in speech-language, reading and writing). AAC incorporates the individual's full communication abilities and may include any existing speech or vocalizations, gestures, manual signs, and aided communication. AAC is truly multimodal, permitting individuals to use every mode possible to communicate. The ability to use AAC devices may change over time, although sometimes very slowly, and the AAC system chosen today may not be the best system tomorrow. In any case, an AAC system is an integrated group of four components used by an individual to enhance communication. These four components are symbols, aids, techniques, and/or strategies

Are there prerequisites to use AAC?

There are no prerequisites to use AAC. The currently accepted evidence in the literature suggests that no specific skills are prerequisite for successful use of AAC in the broadest sense.  AAC is an intervention approach that can be the beginning of communication development for an individual. There are a number of AAC options available to begin the intervention process.

For more information: 

How does my child's cognitive age relate to his/her learning to communicate?
Position statement of the National Joint Committee

What is meant by aided versus unaided forms of communication?

Typically, forms of AAC are divided into two broad groups, known as unaided and aided forms of communication. Unaided forms of communication consist of nonverbal means of natural communication (including gestures and facial expressions) as well as manual signs and American Sign Language (ASL). These forms of communication can be employed by children and adults who are able to use their hands and have adequate fine-motor coordination skills to make fine-grained production distinctions between handshapes. Of course, communication partners must be able to understand the signs for communication to be functional.Aided forms of communication consist of those approaches that require some additional external support, such as a communication board with visual-graphic symbols (i.e., pictures, photographs, line drawings, Blissymbols, printed words, traditional orthography) that stand for or represent what an individual wants to express or a sophisticated computer with symbols, words, letters, or icons that "speaks" for its user via either synthetically produced speech or recorded natural (digitized) speech. From laptop computers that talk as well as perform a wide range of other operations (e.g., word processing, World Wide Web access) to computer linked devices dedicated to communication, technological advances during the 1980s and 1990s have produced numerous vehicles for communication.

Access to aided forms of communication can be via direct selection or scanning. Recent technological developments now permit the use of both direct selection and scanning in the same device. Direct selection includes typing or pointing with a hand, a head stick, or the user's eyes to indicate symbols from a set of choices. From an array of four picture symbol choices that represent toys, for example, a child can use his/her finger to point to the picture of the specific different toy with which he/she wants to play.

An interdisciplinary team is involved in decision making. Speech-language pathologists may work with occupational therapists, who may assist with choices of forms of AAC as well.  Physical therapists may provide evaluations related to seating and positioning for communication.

For more information:

Beukelman, D.R., & Mirenda, P. (1998). Augmentative and alternative communication 2nd ed. Baltimore, MD: Brookes. 

Lloyd, L.L., Fuller, D.R., & Arvidson, H.H. (Eds.), Augmentative and alternative communication: A handbook of principles and practices. Boston: Allyn & Bacon.

Does the child have to understand the symbols on the device before I add them?

Not necessarily. Often new symbols are included on a communication board or device because they will be taught in context, and having them available 1) allows the communication partner to demonstrate their appropriate use and 2) allows the augmented communicator to experiment with their selection. With a voice output communication device, the availability of auditory feedback can be very helpful in learning to associate a symbol with its meaning. On the other hand, if the intent is immediate functional use of the device, a child is going to be hard-pressed to communicate effectively with symbols s/he doesn't already know. It is usually best to teach one new thing at a time, so if device operation is the goal, stick to known symbols. If language teaching is the goal, introduce new symbols in the context of a familiar device and/or familiar communication situation. 

Who uses AAC and how do I know AAC is right for my child?

By recent estimates, well over two million persons who present with significant expressive language impairment use augmentative or alternative communication (AAC). AAC users encounter difficulty communicating via speech due to congenital and/or acquired disabilities occurring across the lifespan. These conditions include but are not limited to autism, cerebral palsy, dual sensory impairments, genetic syndromes, intellectual disability, multiple disabilities, hearing impairment, disease, stroke, and head injury.

AAC is probably right for your child when he or she presents with a severe expressive communication impairment that interferes with or prevents with development and use of oral language. The decision to introduce AAC should be made in consultation with a team of professionals who can assist with issues specific to system/device prescription, procurement, and use. The lead professional in this endeavor will typically be the speech-language pathologist. Others who might be involved include but are not limited to occupational therapists, physical therapists, rehabilitation engineers, special educators, vision specialists, audiologists, and psychologists. Finally, when considering AAC, parents and professionals must remember that there are no prerequisites to AAC use. That is, all individuals should have access to AAC systems or devices that promote effective communication. 

Who would I contact to learn more about AAC?

There are several sources of up-to-date information about research, practice, and policy issues and AAC.  Professional organizations whose members serve persons who use AAC are an essential source for information. They include, for example, American Association for Mental Retardation; American Occupational Therapy Association; American Physical Therapy Association; American Speech-Language-Hearing Association; Council for Exceptional Children Division for Communicative Disabilities and Deafness; RESNA; TASH; and United States Society for Augmentative and Alternative Communication. Each of these groups offers print and electronic forms of information through newsletters, journals, web sites, listservs, and chat rooms. Each also conducts annual conferences that include presentations and instructional courses on the topic. These eight groups are also members of the National Joint Committee for the Communication Needs of Persons with Severe Disabilities (NJC). Resources are posted on the NJC Web site as well.

For more information:

How do you decide what kind of symbols or what kind of AAC device to use?

Designing an AAC system that employs graphic symbols for an individual user necessitates decisions about the type of communication device and the type of symbols that will be displayed. The selection of symbols and of a device is determined by the communication and linguistic profile of the intended user. This is not a simple task because an individual's ability to communicate successfully may hinge largely on the accurate representation of words, phrases, or expressions that span a range of communication functions. One issue to consider is the representational nature or type of symbols themselves. Symbol sets vary from picture-like graphics (e.g., Picture Communication Symbols Mayer Johnson) to the combination of different elements or forms to depict meanings (e.g., Blissymbols). For individuals with some orthographic skills, symbol selection may not be an issue because by using letters, they can produce any possible words or sentences by spelling out their messages. Issues to consider in the selection of devices are their capacities in terms of the number and size of the symbols available, and the type of display (static, dynamic) offered.   

The use of symbols that may closely represent the actual referent or meaning may offer an easy entree to symbol learning and communicative use. This feature is called symbol iconicity. The photograph of a car, for example, would more closely resemble a line drawing of the car and thus be viewed as more iconic. Sometimes the term guessability has been used or the likelihood of determining a symbol's meaning by its resemblance to the actual item it represents. Though it would seem that the easier path to symbol learning would be to use symbols with iconic value, the task is actually a more complex one. Judgments about the iconicity of a specific symbol can vary across individuals (e.g., Franklin, Mirenda, & Phillips, 1996). In contrast, the selection of more abstract or arbitrary symbols might appear on the surface to be more difficult initially, but may offer potential gains as the individual develops symbolic skills. Sometimes symbol set selections are made for other types of reasons, such as the ability to produce the images easily and efficiently.

Other decisions about the device itself include the number of symbols available to the individual at a single time or available in total. A related issue is the size of the symbols displayed on the device at one time. Clearly, within a finite area, the size of an individual symbol and the number of symbols that can be displayed at a single time will impact one another. The individual's own visual and motor skills also must be considered in determining the best symbol x number x size displays. Different demands are placed on AAC users who operate on static versus dynamic displays. In static or fixed displays, symbols are arranged on individual pages; the symbols do not change position on the display. In such systems, one page is physically removed and replaced by another in order to access additional vocabulary. In other types of displays, dynamic displays, touching a single symbol allows the student to access multiple overlays automatically. Clearly, the differences in these two types of displays include not just the access to vocabulary, but make distinct demands on the type of memory skills needed as well.

For more information:

Mineo Mollica, B. (2003). Representational competence. In J.C. Light, D.R. Beukelman, & J. Reichle (Eds.), Communicative competence for individuals who use AAC (pp. 107–145). Baltimore: Brookes.

Sevcik, R.A., Romski, M.A., & Wilkinson, K.  1991. Roles of graphic symbols in the language acquisition process for persons with severe cognitive disabilities.  Augmentative and Alternative Communication, 7, 161–170.

Wilkinson, K.M., & McIvane, W.J. (2002). Considerations in teaching graphic symbols to beginning communicators. In J. Reichle, D.R. Beukelman, & J.C. Light (Eds.), Exemplary practices for beginning communicators (pp. 273–321). Baltimore: Brookes. 

What considerations are there when determining the best mode of communication to target in intervention? For example, are pictures always better than signs?

The best form or forms of communication for any individual are those that the individual will use to communicate with other people. One variable affecting use is understandability, and understanding is affected by many contextual variables such as the familiarity of the communicative partners with different modes of communication (signs, pictures, speech-generating devices).

A common view among SLPs and other communication specialists is that an individual will eventually use pictures more than other forms of communication because pictures may be more readily understood by a range of communication partners in various environments. Each type of communication takes time and cognitive resources. For signs, the communicator has to recall and produce the motor movements. For pictures, the communicator has to locate and select the pictures. Perhaps for these reasons some individuals with severe cognitive disabilities may prefer to use signs (rather than pictures or photographs) when communicating with partners who understand sign language.

For these individuals it can be helpful to encourage (and teach) multiple forms of communication. Individuals may need to be taught when it is appropriate to use different types of communication. For example, the individual may sign when interacting with parents at home but may use a picture-based system with nonsigners. Individuals with very complex needs and a limited communication repertoire can learn to use different systems in different contexts (Blackstone & Hunt Berg, 2003; Reichle, 1997).

Speech-generating devices also provide a way for an individual with severe cognitive disabilities to communicate independently because they produce spoken communication even though the individual is using pictures to create the message. These spoken messages can be readily understood by communication partners who may not be familiar with sign language. 

How should I approach parents about AAC when they are only interested in having their child learn to speak? Many parents seem concerned that AAC will interfere with speech.

Conveying difficult information to a parent can be tricky, especially when expectations are high. Here are a few tips: First, be respectful of the family's hopes and dreams. Acknowledge that all involved want the child to be verbal. Second, share the notion of development being a process. It might be helpful to make a timeline with developmental stages clearly marked. This can help illustrate a child's progression to speech. Third, share positive and negative prognostic indicators that may impact progression along the developmental timeline. For example, research has shown that the presence of consonants is a positive indicator for verbal development. Fourth, share that existing research supports the use of unaided and aided AAC with children with severe disabilities. It fact, it is clear that AAC does not prevent the emergence of speech (for a review of research visit the AAC Connecting Young Kids Web site). Finally, note that the most important outcome for the child should be improved communication. Although communication includes speech, it also includes much more, such as gestures, facial expressions, sound making, and aided AAC.

We all want children with severe disabilities to be verbal communicators. This said, we must remember that verbal communication is the result of developmental, physical, and environmental influences. Some children simply may not be at a developmental level consistent with speech. Others may not have the physical structures necessary to use intelligible speech. Children such as these will benefit from treatments targeting nonverbal and/or augmentative communication. An example might be a child who is 36 months old, yet communicates to request through nonverbal means such as cries, reaches, and touches. Appropriate treatment targets for this child may include expanding nonverbal communication to express intentions other than requesting (e.g., protesting, greeting, showing off, and commenting). It might also be appropriate for this child to pursue treatment targets that involve communication through aided AAC. 

How do I decide whether a high technology communication device or a low technology communication device is better for an individual?

Selecting communication devices is not an "either or" decision. People communicate in a variety of ways and therefore, one device will not meet the person's needs in all situations. It is important that a clear picture of the individual's current capabilities and needs are considered in order to select communication devices, communication techniques, and the symbol systems or symbol sets.

It is also important to contrast the "high" and "low" tech devices. The advantage of using nonelectronic communication options ("low tech" or "light tech") is that these displays can take on many forms and can be tailored to the abilities and needs of individuals across various activities. The primary advantage of electronic devices ("high tech") is that they provide output or "talk". When the individual touches a symbol on a high tech device, output for the message is relayed generally with voice output. Using electronic or high tech devices in conjunction with other techniques and or low technology options. may best serve the person's need to communicate.

For more information:

Downing, J. (1999). Teaching communication skills to students with severe disabilities. Baltimore: Brookes Publishing. 

Can sign language help improve my child's communication?

Many children with communication disorders have learned to communicate with sign language. Like other forms of augmentative and alternative communication (AAC), sign language may enable a child to communicate when they are unable to adequately communicate with speech. For some children, sign language appears to provide an important first step for later spoken language development. Other children continue to rely on sign language as their primary communication mode. Sign language can be easier to teach than speech because parents and teachers can help children form the hand shapes of sign language. It is important for communication partners to also learn sign language so that they can model and reinforce the signs the child is learning. There is no research indicating that sign language delays spoken language development.

For more information:

Abrahemsen, A., Cavallo, M., & McCluer, J. (1985). Is the sign advantage a robust phenomenon? From gesture to language in two modalities. Merrill-Palmer Quarterly, 31(2), 177–209.

Acredolo, L., & Goodwyn, S. Baby Signs: How to talk with your bably before your baby can talk. Chicago: Contemporary books.

Carr, E.G., Binkoff, J.A., Kologinsky, E.,& Eddy, M. (1978). Acquisition of sign language by autistic children. 1: Expressive labelling. Journal of Applied Behavior Analysis, 11, 489–501.

Gaines, R., Leaper, C., Monahan, C., & Weickgenant, A. (1988). Language learning and retention in young language-disordered children. Journal of Autism and Developmental Disorders, 18, 281–296.

Layton, T.L., & Savino, M.A. (1990). Acquiring a communication system by sign and speech in a child with Down syndrome: A longitudinal investigation. Child Language Teaching and Therapy, 6, 59–76.

Sigafoos, J. (1995). Testing for spontaneous use of requests after sign language training with two severly handicapped adults. Behavioral Interventions, 10(1) , 1–16.

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