Augmentative and Alternative Communication
Augmentative & Alternative Communication (AAC) refers to any technique or aid that supplements, replaces, or enhances conventional communication methods, such as speech or writing. When a person is unable to communicate effectively with traditional methods of expression, these techniques are used to enhance (augment) or completely replace the individual's mode of communication. Most of us incorporate conventional AAC methods into our own communication, including hand gestures, facial expressions and head nodding. Telephones, TTYs, fax machines, computers, and typewriters are also used to communicate ideas and needs. These AAC methods are used by most of the general public. Many forms of AAC have been developed specifically for people with severe communication difficulties. These forms typically fall into two categories: aided techniques, such as communication boards & electronic devices, and unaided techniques, such as sign language and gestures.
The most effective & functional AAC intervention for an individual is determined through an assessment, and should always use the team approach. The inter-disciplinary team traditionally includes a speech language pathologist, occupational therapist, the individual and his or her family members, an educator and rehab engineer. The age, disability and goals of each individual will determine the makeup of the assessment team. Physical therapy, vocational rehabilitation, psychology, social services, recreational therapy, vision therapy, audiology, and medicine are other disciplines which may be involved in the assessment. The individual and their family members are the most important part of the process, and should be included in all components of the intervention. This includes the needs assessment, defining goals, identifying characteristics or features that will best meet the individual's communication needs, and then matching these features to the most suitable or appropriate system. In addition, the assessment may provide information on funding sources, and make recommendations for training and follow-up services. All AAC assessments should be guided by the needs of the individual.
The purpose of the team assessment is to determine the communication needs of an individual based on their physical, cognitive and language abilities, while also taking into account the environmental factors that will affect modes of expression. It is therefore very useful to perform the assessment in the environment or environments where the individual will be using the communication system. To enable the individual to communicate effectively, an AAC evaluation includes the following steps:
Low-Tech Communication Devices
This form of AAC typically refers to communication boards, displays, or wallets ("manual" indicating the use of the hands). Language is displayed using pictures, photographs, objects (e.g. soda can, cup, toy, candy bar), textures, letters of the alphabet, words, symbols, or a any combination of these. This type of system is accessed by pointing; using a finger, headwand or lightpointer, or eye-gaze to indicate needs and ideas. Typically, manual communication boards are used as an introduction to AAC and electronic devices, although they are not always a precursor to the use of high-tech devices. However, they have proven beneficial as a communication aid for individuals who are just beginning to recognize abstract concepts through pictorial representations; as a tool for emergent literacy; and for individuals who are functioning at a lower level, and/or are sensitive to, or do not respond well to auditory feedback. They are also a very important component for high-tech users, both as a complement to an electronic device and as a back-up system. These systems are fairly inexpensive and relatively easy to create.
High-Tech Communication Devices
These systems typically fall into two broad categories: dedicated communication systems and computer based communication systems. Dedicated devices are stand-alone systems designed for communication. However, they incorporate voice and can include printers and other features. Computer-based systems are typically laptop computers that incorporate communication software and usually a speech synthesizer; and can be used for other applications as well as for communication.
For the majority of high-tech AAC devices, language is generated through pictures, symbols, traditional writing, or a combination of these. Pictures or symbols may be used to represent a word, phrase, sentence or concept. These may be sequenced together, meaning two or more pictures are selected to create a phrase or sentence. Language is then "spoken" using either synthesized speech, digitized speech, or a combination. Synthesized speech uses a computer chip to generate spoken words from written text, based on phonetics. Digitized speech is an actual recording of an individual's voice, and requires more memory than synthesized speech. If digitized speech is the sole output method, however, it eliminates the ability to communicate spontaneously, since every word, phrase & sentence must be thought out beforehand and recorded into the device. Many devices allow language to be created on different levels. For example, the first level may be used to represent communication concerning activities at home; the second level for school activities, and the third level for church related activities. The amount of language created utilizing different levels, in conjunction with sequencing, is limited only by the amount of memory in the device.
Other systems have a single level or overlay, and allow generation of unique messages by combining or sequencing pictures in different ways. When traditional orthography is used messages can be spelled, or rate enhancement techniques such as abbreviation expansion or word prediction can be used . These types of features increase the cognitive and sensory/perceptual demands of the user.
Selection techniques for accessing communication systems are varied and often unique. With an appropriate access evaluation, a selection technique can be identified for anyone. Direct selection means the individual can access the device using their hands, a headstick, mouthstick or other typing aid, or an infrared or light-pointing device. Scanning is typically used by individuals who cannot direct select because of physical limitations. In visual scanning, the vocabulary on the communication device is "highlighted" in a predetermined manner (one cell at a time, by row then column). When the selection the individual wants to access is "lit up," speech is generated by activating a switch. Or, the switch may be held down until the appropriate selection is highlighted. When the switch is released speech will be generated. Auditory scanning is an option for individuals who are blind or visually impaired. With auditory scanning, selections are verbalized to the user through a small, external speaker. When the message they wish to express is heard, it may be verbalized to the communication partner by activating a switch. Communication systems may also be accessed through other indirect means, such as a joystick or trackball.
The type of communication system selected for an individual will depend on their sensory, motor, language, and cognitive levels. Other considerations include the portability of the system, how it will be mounted and/or carried, and expected battery life. How well does it stand up to typical daily wear and tear (being dropped, exposed to fluids)? Does the manufacturer have a toll free number for service & technical assistance? Is the system easy to program and use? How easily can changes be made? What is the "growth potential?" That is; does the device have the capacity to grow as the user's needs change? It is important to look at the way the person is communicating now, and to try and modify or blend some of those methods into the AAC system.
Information Resources:American Speech, Language, Hearing Association
Manufacturers of Communication Products:Ability Research,
For more information on assistive technology, please contact:Jill Oberstein, Project Director Arizona Technology Access Program
AzTAP provides support to five Regional Resource Centers (RRCs) in Arizona. These RRCs provide direct assistive technology services to persons with disabilities, and are available to help consumers select the most appropriate devices, and advocate for themselves in order to acquire funding for devices and services.ASSIST! To Independence
This document was developed by the Arizona Technology Access Program. Funding is provided by the U.S. Department of Education, National Institute on Disability and Rehabilitation Research (NIDRR) Grant #H224A40002. The contents of this publication do not necessarily reflect the views of NIDRR or the U.S. Department of Education, and do not imply endorsement by the U.S. Government.
Please contact the AzTAP office for a copy of this material in an alternate format. Rev. 07/01