American Speech-Language-Hearing Association

AAC: More Than Three Decades of Growth and Development

by Rose A. Sevcik and MaryAnn Romski

For more than three decades now, the field known as Augmentative and Alternative Communication (AAC) has addressed the communication needs of individuals who cannot consistently rely on speech for functional communication. Tracy Rackensperger, whose article precedes ours, has grown up with AAC. Her story highlights for us developments in the hardware, software, and speech output options available to an AAC user from the 1980s to the present. The capabilities of devices have become more sophisticated, and as Rackensperger indicates, the intelligibility of the accompanying voice output has improved substantially. Along with the technological advances that support AAC, there have been developments in the empirical knowledge base that support new approaches in clinical assessment and intervention decision making.

For example, some speech-language pathologists (SLPs) use AAC as a last resort only when all attempts at natural speech have failed, mistakenly thinking that AAC will hinder natural speech development and use. Recent research suggests just the opposite. Depending on the individual's communication needs, AAC can be used to supplement existing speech, as Rackensperger has indicated, and replace speech that is not functional. Research has also shown that AAC can be employed as part of language intervention strategies to develop children's speech and language skills. Some children who employ AAC systems may develop vocal and spoken language skills after experience with AAC.

AAC Defined

ASHA 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 severely speech-language and writing impaired). 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 as Rackensperger so clearly illustrates, 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.

Who Uses AAC

Those who encounter difficulty communicating via speech cross the life span from the young child to the older adult. Children who cannot use speech are either born with some type of congenital disability that hinders their development of speech (i.e., autism, cerebral palsy, dual sensory impairments, genetic syndromes, mental retardation, multiple disabilities, hearing impairment, a stroke at or near birth) or sustain an injury or illness that substantially limits their extant speech and language abilities (i.e., a traumatic brain injury caused by an accident, stroke, or, in a rare instance, severe psychological trauma). Some children's difficulty with speech remains over the course of their life, and thus some adults who use AAC, like Rackensperger, were once children who used AAC.

Adults may also become nonspeaking for a wide range of causes, including a stroke that results in aphasia, cancer that affects the vocal mechanism, traumatic brain injury, or a progressive neurological disease (e.g., Parkinsonism, Multiple Sclerosis, or Amyotrophic Lateral Sclerosis (ALS)). Not every child or adult presenting with one of these disorders is, or will be, unable to speak. Some of the adult-onset disorders that are progressive in nature may result in significant difficulty with speech later rather than earlier in the course of the disorder. As with all abilities and disabilities, there are individual differences in communication patterns.

Accessing Communication via AAC

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.

For some children and adults, direct selection is not a viable means to access a device because the severity of the individual' s physical disabilities limit motor control. In these cases, the items to be selected either are displayed by another person (e.g., a familiar knowledgeable communication partner) or by an electronic communication device (e.g., a computer that talks for its user) in a predetermined configuration or pattern. The AAC user must wait while a person or the device proceeds through items and reaches the item of choice. The AAC user then chooses the item by indicating a yes or no answer to a question, or by activating a switch. This type of selection is called scanning. There are many types of scanning including those that use vision (e.g., row column scanning, linear scanning) or hearing (e.g., auditory scanning). Although there is limited research evidence, it is generally presumed that scanning requires less motor control but more cognitive skill than direct selection, which, in turn, is believed to require less cognitive skill and more motor control.

Advances in the AAC Field

Research findings show that everyone can communicate. The field's focus has moved away from an assessment of devices-who can use what type of AAC device and a concentration on the technology per se-and onto the development and refinement of effective interventions that promote functional communication use, along with broader issues of consumer advocacy and social policy. Communication interaction research has focused on specific behaviors such as communicative functions (e.g., requesting, questioning) as well as enhancement of the rate and quality of interaction.

Another important area of research, particularly with changes in our health care system, is efficacy or outcomes of intervention strategies for individuals who use AAC. Here research is focused on the development of measurement tools to assess the broad range of functional communication outcomes possible from simply learning a new vocabulary word to communicating with a broad audience in a public speech. In January 2000, the ASHA Special Interest Division 12 hosted a Leadership Conference that addressed aspects of this issue. Division 12 will continue their work in the 2001 Leadership Conference focused on models of assessment (see story on page 13).

AAC research is answering questions that influence social policy decisions but a substantial amount of uncharted territory remains to be studied. More and more, SLPs are providing AAC interventions and making a difference in the lives of many children and adults and their families who encounter significant difficulty communicating. AAC is the essence of what our field is!

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Rose A. Sevcik is an Associate Professor of Psychology at Georgia State University in Atlanta. She currently serves as Coordinator for ASHA Special Interest Division 12: AAC.

MaryAnn Romski is a Professor of Communication, Psychology, and Educational Psychology & Special Education at Georgia State University. They have more than 20 years of research focus on the communication development of children with severe developmental disabilities and the formulation of interventions to facilitate children's communication.

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