Figure 5.

Size demo (Experiment 2). A red dot marks the center of the left flanker. In each row, fixate the plus sign and try to identify the middle object from the set of possible targets shown in the bottom row. In the first row, you can identify the target. In the second row, the center spacing is the same as in the first row, but it is very hard, if not impossible, to identify the target. In the third row, the edge spacing is the same as in the first row, and it is just as easy to identify the target as in the first row. For lopsided rectangles, equal edge spacing preserves crowding.