Psychophysical studies have revealed that retinal and depth periphery play a dominant role in activating vection, or visually induced sensation of self-motion. But since abstract stimuli such as random-dot patterns and vertical stripes have been used in these studies, the results are not always applicable for designing more realistic visual displays in real-world applications. Indeed, it has been shown that for human orientation, a real-world display is more effective than an abstract one (Howard and Childerson, 1994 Perception 23 753 – 762). We investigated how vection was controlled by the peripheral part of a stimulus consisting of a real-world display. Stereoscopic and nonstereoscopic video clips were taken through a windshield while driving on (i) a straight, (ii) a gradually curved, and (iii) a sharply curved road at slow and fast speeds. Vection was measured with these stimuli which were presented on a 63 deg wide and 38 deg high video projection monitor. The results showed that although the stereoscopic display generally activated more forward and sideways vection than the nonstereoscopic one, the difference was barely statistically significant. When only the central 18 deg diameter of the display was presented, similar vection was activated as with a full field display. When the central 40 deg diameter of the display was occluded, vection did not change significantly, though observers found difficulty in assessing the direction of self-motion. It is concluded that retinal and depth periphery of real-world stimuli do not play a significant role in activating vection.
