Information presentation for a wearable messenger device

In this paper we address the question of how message presentation can be optimized given the constraints of a wearable messenger device. The device delivers short messages and is equipped with a small screen and an earplug for speech output. Due to hardware and software limitations, text can be presented on the screen in chunks, but the pacing of the chunks cannot be fully synchronized with the speech. An experiment was conducted to assess the effect of five different presentation modes: speech only, text chunks only, speech+text chunks, full text at once, and speech+fulltext at once. The latter two conditions were included as control conditions. Subjects reported main concepts in each message right after presentation. It was found that the "speech+full message at once" condition resulted in a better performance than the "speech only" condition, but that it was not better than the "full text message at once" condition; the "speech+text chunks" condition resulted in a better performance than the "text chunks only" condition, but it was not better than the "speech only" condition. The results show that uni-modal presentation of text alone or speech alone may be as effective as simultaneous multi-modal presentation of text and speech, depending on the concrete details of the presentation.