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(© 2006 Evan Palmer & Phillip Kellman)
The Occlusion Velocity Illusion shown in the video demonstrates that when one part of a moving object goes out of view before another part, the two pieces appear misaligned, even though they are not (top row). This illusion can be counteracted by misaligning one portion of the rod in the direction opposite to the perceived misalignment (middle row). If observers are instructed to attend to the rod’s shape only within the blue box, they are still subject to the illusion (bottom row). This final observation indicates that the illusion is obligatory and not under volitional control.
Read more about the illusion and possible explanations
The Occlusion Velocity Illusion,