Abstract: Introduction: When an individual moves in an environment, his or her cognitive system must simultaneously update information pertaining to the spatial relations between the environment and his or her body; this is termed as spatial updating. Similarly, when an individual imagines himself or herself or the surrounding objects to be rotating, the representation of the spatial relations between him or her and the surrounding objects will be updated; this is known as image updating. Wraga et al. (2000) found that egocentric image updating had an advantage over array-centered image updating. Further, Zack et al. (2003) found the different brain activation patterns between them. This suggested that there were two different processing subsystems underlying both egocentric and array-centered image updating. Based on the conflicting-of-reference model of spatial updating, developed by Presson et al. (1987), the present study aims to examine whether conflicting reference frames influence egocentric and array-centered image updating, and if so, how can it be realized.
Method: The study included four experiments that were attended by 64 undergraduates, aged between 18 and 23. The participants were unaware of the purpose of the experiments; further, all participants had normal or corrected-to-normal vision. Acting as stimuli, 3D pictures representing a scene were drawn using 3ds max 6.0 software. Stimulus presentation and data collection were controlled by a Lenovo microcomputer using the E-Prime software. The effects of conflicting reference frames under the baseline condition were tested in experiment 1. In experiment 2 to 4, conflicting reference frames were systematically manipulated to explore their effects on the two kinds of image updating.
Results: The results indicated the following. First, conflicting reference frames had significant effects on egocentric image updating; however, in comparison, they had comparatively minor effects on array-centered image updating. As a result, the self-rotation advantage of image updating decreased gradually, and eventually disappeared. Second, the effect of conflicting reference frames caused by tilted observers was unequal to that caused by tilted scenes in that the former was smaller than the latter. Finally, the effect of conflicting reference frames on array-centered image updating diminished if a local spatial reference frame was included in the scene and was tilted at the same angle as the scene. However, at the same time, the effect of conflicting reference frames on egocentric image updating was unaffected by this experimental manipulation.
Conclusions: The results suggest that there were different cognitive mechanisms underlying egocentric and array-centered image updating. Moreover, the results extended the conflicting-of-reference model developed by Presson et al

Key words: spatial updating, image updating, conflicting reference frames, imagined self-rotation, imagined array rotation