TITLE: ORGANIZATION OF PRE-STORED TEXT IN ALTERNATIVE AND AUGMENTATIVE COMMUNICATION SYSTEMS: AN INTERACTIVE SCHEMA-BASED APPROACH AUTHORS: Peter Bryan Vanderheyden COMMENTS: Master's Thesis; ASEL Technical Report ABSTRACT: The field of augmentative and alternative communication (AAC) is concerned with assisting individuals with severe physical and language impairments to communicate more effectively. Existing AAC systems make use of a variety of approaches to accelerate sentence generation, including different selection methods, encoding strategies, and natural language processing. Augmented communicators continue to produce words at a very slow rate, and have difficulty participating actively in conversation. However, only recently have AAC systems begun to make use of the predictable patterns that occur in conversation. To date, such systems have focussed on either highly constrained and relatively content-free utterances, or on loosely structured, monologue type text. This thesis develops an alternative but compatible approach to facilitating conver sational participation in AAC which attempts to target a broader range of conversations, representing both their content and structure. Motivated by schema theory, this approach applies schema structures to the domain of conversation. A set of structures is proposed with which text from past conversations can be made available for reuse. To demonstrate this approach, a prototype is developed and evaluated. The prototype behaves as an interface that augments a user's current AAC system by providing access to conversational schemata created and updated by the user. In the evaluation study, two individuals used the interface while taking part in a series of mock job interviews. Results of the study were encouraging.