Prosody to Improve Usability of a Speech-Based Interface

This paper investigates the addition of prosody to a synthetic speech presentation of algebra notation in an algebra workstation for blind people. Prosody and lexical cues were evaluated in terms of their impact on disambiguating an utterance, enhancement of the retention of content and its contribution to mental workload. Prosodic cues alone performed better than the more traditional lexical cues on all three counts. These factors indicate that prosody can make a synthetically spoken algebra expression more usable. The addition of prosody to synthetic speech has a general application in presenting complex information whose syntax is known.