An augmentative communication interface based on conversational schemata

Abstract

Many people with severe speech and motor impairments make use of augmentative and alternative communication (AAC) systems. These systems can employ a variety of techniques to organize stored words, phrases, and sentences, and to make them available to the user. It is argued in this chapter that an AAC system should make better use of the regularities in an individual's conversational experiences and the expectations that the individual normally brings into a conversational context.

An interface and methodology are described for organizing and retrieving sentences appropriate to a particular conversational context, sentences that were possibly developed from earlier conversations. These conversations are represented according to the schema structures discussed by Schank as a model for memory and cognitive organization [16]. The interface allows the user to proceed with minimal effort through conversations that follow the schema closely, and facilitates the derivation of new schemata when the conversation diverges from existing ones. This interface, called SchemaTalk, is intended to operate in parallel with and to complement a user's existing augmentative communication system. The results of preliminary investigations into the effectiveness of the interface and methodology have been encouraging; further investigations are planned. Of interest for future study is how the use of schematized text might influence the way that augmented communicators are perceived by their conversational partners. Possible design modifications to improve the usability of the interface are also under investigation.

Much of the work upon which this chapter is based was completed while the first author was at the University of Delaware Center for Applied Science and Engineering, located at the duPont Hospital for Children, in Wilmington, DE.