Experiment AIE1, which studied 16, 32 and 48 FOV conditions, did not show a uniform pattern in the reported presence data. Nor was there a uniform pattern in the visual-inertial nulling data for these conditions, as reported in Section B.2. In order to test whether a clear main effect for both measures could be found in the predicted direction, it was decided to study a different manipulation. The manipulation chosen was to compare a meaningful to a random scene. It was hypothesized that the meaningful condition would produce higher values on both the nulling and reported presence measures.
This meaningful/random manipulation was motivated in part by Experiment CogE1 (see Appendix A), which showed a main effect in the direction of higher reported presence for meaningful as compared to meaningless stimuli. Unlike the meaningful/meaningless manipulation of Experiment CogE1, the meaningful/random manipulation studied here affects low-level perceptual factors, such as number and distribution of edges.