(Transparent) Motion Aftereffect Demos
The demos below all demonstrate Motion Aftereffects after adaptation to transparent (bivectorial) motion. Three types of test patterns are used: a Static (binary noise) test pattern, a Dynamic test pattern consisting of dynamically refreshed binary noise, and a test pattern that is a combination of the two. The latter test pattern will result in a Transparent Motion Aftereffect when the speeds of the two adaptation components are chosen correctly, as described in: van der Smagt MJ, Verstraten FAJ & van de Grind WA (1999): “A New Transparent Motion Aftereffect”, Nature Neuroscience, 2 (7), 595-596. doi: 10.1038/10150
Requirements
- Most modern computers and graphics cards are sufficient. Due to the recent advances in screen resolution, make sue you are not too far away from the monitor. For best effects, the 256×256 pixel movies should span a visual angle of about 8 degrees.
- A CRT/data-projector with a vertical refresh rate of at least 75 Hz is best as well. On most LCD screens this is down-sampled to 60 Hz, though. It still works but especially the faster adaptation component is much less potent.
- A movie player that can play Apple Quicktime movies (with Apple animation codec). The Apple Quicktime software is available for both Windows and Mac.
Note that the demos might run better when downloaded on your HD instead of running them from within your browser.
Classic.mov
The ‘classic’ MAE of adaptation to orthogonally directed transparent motion. After adaptation a static test pattern appears. The MAE should appear unidirectional and going straight up.
Dynamic.mov
The same as the ‘classic’ MAE to adaptation to orthogonally directed transparent motion, but now using dynamic noise as test pattern. Although harder to spot in this demo, the overall direction of the MAE is still unidirectional and going straight up.
TransMAE_orth.mov
The transparent MAE. Adaptation is again to orthogonally directed transparent motion. One of the adapting components is fast, while the other slow. The test pattern consists of a static pattern as well as dynamic noise. A transparent MAE is perceived, in which the static test component seems to move slowly opposite the slow adaptation component, whereas the dynamic test component appears to move rapidly opposite the fast adaptation component.
TransMAE_same.mov
The same as TransMAE_orth.mov, but now the slow and fast adaptation components move in the same direction. In the combined static and dynamic test pattern the static component moves slowly opposite the adaptation direction, while the dynamic component moves rapidly in the same direction, thus ‘sliding over’ the static component.
TransMAE_opp.mov
The transparent MAE, with oppositely moving adaptation components.