Mathtalk: Usable Access to Mathematics‪.‬

INTRODUCTION This paper describes the design of a user interface that aims to enable a visually disabled reader to gain an active reading of standard algebra notation using synthetic speech and non-speech audio. Two concepts are central to this paper, "external memory" and "information flow control." The aim is to relieve the reader's mental demands and to make them active in reading complex material, in this case algebra. The paper describes the Mathtalk program, which uses prosodic cues in synthetic speech to improve the usability of the auditory presentation and browsing to make the reading process active. Two facilities are important in making the reading process active: browsing and planning. Mathtalk includes browsing functions that are powerful but easy to use and an "audio glance" that facilitates the planning of the reading process. It is hoped that the design principles used in the design of the Mathtalk program can be extended to interfaces that facilitate reading many types of complex information.