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AUGMENTATIVE AND ALTERNATIVE COMMUNICATION SYSTEMS

The history of using augmentative and alternative communication (AAC) systems for communication is rather brief. Prior to 1975, there were descriptions of nonspeaking individuals using simple letter boards, picture boards, and typewriters to communicate messages (Goldberg & Fenton, 1960; Goldstein & Cameron, 1952; McDonald & Schultz, 1973; Vicker, 1974). The early use of AAC systems was limited to a few individuals with physical handicaps or aphasia who had the ability to independently point to symbols. Several factors came together in the late 1970s that had a major impact on the development of AAC devices. In 1975, PL 94-142 was implemented, mandating that all handicapped children between 5 and 21 years of age be provided with a free public education. With the implementation of this law, nonspeaking individuals who previously had been excluded from the educational mainstream began receiving the attention of speech-language pathologists and educators. The development of microcomputer technology was the second factor that impacted the AAC field. Prior to the development of microcomputers, AAC devices were handmade electrical systems, or nonportable computer systems. Vanderheiden and Grilley (1977) offered an overview of electronic AAC devices that were available in the early 1970s. Many of these early AAC systems consisted of adaptations to electric typewriters, or were simplistic electronic scanning devices without printed or spoken output. The Canon Communicator was one of the first commercially available augmentative communication devices specifically designed for nonspeaking individuals. It was a small device that strapped to the user's wrist. A small touchpad with alphabet letters could be used to spell messages which were printed on a small strip printer. The Canon Communicator could only be used by individuals with sufficient spelling and fine motor abilities. A modified version of the device is still available commercially (see Appendix). The AutoCom was of one of the first computerbased electronic AAC systems that could