Designing auditory cues to enhance spoken mathematics for visually impaired users

Visual mathematic notation provides a succinct and unambiguous description of the structure of mathematical formulae in a manner that is difficult to replicate through the linear channels of synthesized speech and Braille. It is proposed that the use of auditory cues can enhance accessibility to mathematical material and reduce common ambiguities encountered through spoken mathematics. However, the use of additional complex hierarchies of non-speech sounds to represent the structure and scope of equations may be cognitively demanding to process. This can detract from the users' understanding of the mathematical content. In this paper, a new system is presented, which uses a mixture of non-speech auditory cues, modified speech (spearcons) and binaural spatialization to disambiguate the structure of mathematical formulae. A design study, involving an online survey with 56 users, was undertaken to evaluate an existing set of auditory cues and to brainstorm alternative ideas and solutions from users before implementing modified designs and conducting a separate controlled evaluation. It is proposed that by involving a wide number of users in the creative design process, intuitive auditory cues will be implemented with the potential to enhance spoken mathematics for visually impaired users.