76 6 DesigningBlended Reality Spaces Our mental activities are also changed through physical-digital blending, along with some of the ways in which we carry out our intentions. An integrated sense of mediated presence can potentially provide a smoother link between our intentions and actions in any combined physical/virtual situation, including those for users whoarenotfamiliarwithcurrenttechnology.Theexampleofadesignedsystemfor tangiblesocialnetworkingfortheelderlyispresented,asacaseofsatisfyingspecial needs via what we see as an almost universal approach to design. ABlendedRealityGame Blended reality space is essentially an interactive environment where the physical and the virtual are intimately combined. A number of researchers have experi- mented with sensor-based techniques for interacting with virtual entities via the manipulation of physical objects in space. The main idea of such a tangible interface, built on movementand position sensing techniques,is to providephysical forms which serve as both representations of and controls to digital information. The applications make it possible to directly manipulate the digital information with our hands, and perceptible through our peripheral senses through physical embodiment (Ishii 2008; Ishii and Ullmer 1997; Ullmer and Ishii 2000). Through this physical-virtual combination, physical objects provide users with clues about the virtual environment and help them develop skills in that environment, such as picking up, positioning, altering, and arranging objects (Ishii 2008). This definition providesacommonunderstandingoftheconcept,butitdoesnotidentifythefactors influencingthesenseofpresenceinsuchspaces,nordoesitdescribetheexactnature of the experience. Whataspectsdoesblendedrealityspacecontributetotheexperienceofpresence? Motivated by this question, we carried out an experimental study that examined three keyfactorsin the way blendedrealitiesmaybeimplemented(reportedinmore detail in Hoshi and Waterworth 2009): • Theextent to which tangible tools play a role in interaction • Whether a first person or a third person perspective is provided from the user’s point of view; and • If a third person perspective (of a self-representing avatar) is used, how closely the representation matches the appearance of the user. We used the Nintendo Wii video game and console, commonly available and widely used technology that can provide a satisfying and involving gaming experi- enceevenwithrelativelyinexpensivetechnology,includingcomputergraphicswith quite low resolution. The experiment looked at the effect of these variables on rated presence (LombardandDitton1997)andalsoself-presence(Ratan et al. 2007),which is the definedastheextenttowhichapersonexperiencesasenseofidentitywithavirtual characterisation of themselves – an avatar. Our expectation was that a physical tool