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Apparent motion display. A two-frame display in which two dots occupy positions at the top left and bottom right points of an imaginary square at Time 1 (a) and the top right and bottom left points Time 2 (b). Observers generally report that the dots appear to move between the two positions rather than simply appearing. At each position change, dots may be observed to move consistent with the interpretation presented in (c) or that in (d).
