As researchers and practitioners we have been exploring the topic of presence, and in particular the contribution of the sense presence to interactive experiences, for several years. We have learned that the user experience of information technology is profoundly affected by the extent to which we experience ourselves to be really present in the mediated world that the technology makes available to us. Over the last two decades, many researchers, artists and designers have explored the role of the sense of presence in interactive experience (so-called ‘mediated presence’). While there is still not a general consensus about what presence actually is, it is fair to say that most investigators agree about what it is not. Presence is not the degree of technological immersion, it is not the same thing as emotional engagement, it is not absorption or attention or action; but all of these and several other factors have a potential role in understanding the experience of presence in interaction.

The Reality Helmet is an interactive experience, in which the user's vision and hearing is shielded off from the world. Video and sound is nevertheless recorded by the Reality Helmet, but through computer processing it presents sound to the user as vision, and likewise, vision is turned into a soundscape. The result is a form of artificial synesthesia. Other than as an appreciated art installation, which seems to make people calm and reflective, the Reality Helmet is used to explore relationships between the wearer's sense of presence and the kind of realism provided by the interactive environment.

Desktop virtual reality (VR) offers a powerful environment for visualizing structure in large information sets. In well-designed virtual worlds, users can employ skills from wayfinding in the real world. The paper reports on the development and testing of a series of prototype VR worlds, designed to support navigation during information visualization and retrieval. Results indicated that users subjectively preferred naturalistic environments over abstract ones, but that users objectively searched better in environments that had rigorous hierarchical structure, and support for both overview and detail. In comparison with a hypertext interface, the final virtual world design elicited more enjoyment, without worsening search performance significantly, when appropriate training time was allowed. This prototype shows the potential value of navigable VR that is engaging and useful for everyday information exploration.

No abstract available.

No abstract available.

Previous research has demonstrated that synthetic speech is less well recalled than natural speech. Luce et al (1983) concluded that this was because synthetic speech increases the effort involved in encoding and/or rehearsal of presented information. Results of the experiments described here, which involved ordered recall of lists of ten words spoken in either a synthetic or a natural voice, with repetition of the words as a measure of successful encoding, indicate that most of the memory deficit with synthetic speech is due to encoding difficulties, rather than problems with item retention. There is evidence that encoding synthetic speech involves more processing capacity than does encoding natural speech, but that once it is encoded it is stored just as efficiently.