Previous research had suggested that a foreground occlusion can increase vection. Experiment AIIE1 addressed the question of whether it can also increase reported presence. This question is important for both theoretical and practical reasons. The theoretical reason is that the RFC and the presence hypothesis predict a close relationship between vection and presence. Specifically, vection results from one aspect of the selected rest frame (the implied self-motion) whereas presence reflects the selected rest frame in general. Hence, if foreground occlusions increase vection (for possible reasons discussed in Section 3.7.6), then it follows that foreground occlusions should also increase presence. One purpose of Experiment AIIE1 was to test this theoretical prediction.
The practical reason for investigating whether foreground occlusions affect the sense of presence has to do with HMD design. Traditionally, it has been believed that a wide FOV is necessary to induce a strong sense of presence. There is a trade-off between FOV and resolution. Hence, if one wants to increase the sense of presence by increasing the FOV, one needs to lower the resolution. If a foreground occlusion mounted inside an HMD can increase the sense of presence, then it may be possible to have a high level of presence at a low FOV. Experiment AIIE1 investigates this possibility as well.