Comparing effects of navigational interface modalities on speaker prosodics

Displayless interface technology must address issues similar to those of GUI access technology for users with visual impairments. Both must address the issue of providing nonvisual access to spatial data. This research examined the hypothesis that strictly verbal access to spatial datsi places a cognitive burden on the user, which in turn impacts the prosodies, i.e., nonverbal aspects, of the user?s speech. The hypothesis was tested through experiments in which subjects used speech-based, displayless interface followed by a multimodal interface to perform a series of navigational tasks. Their speech was recorded during the experiments and post-processed for prosodic content. Statistical analysis of the post-processed data showed significant differences in subjects? prosodies when using the displayless versus the multimodal interface.