Duration of preceding motion
Click on:

The jump can also be perceived in the same direction as the preceding motion, but only when this motion is very brief, lasting less than 75-150 ms or so. When you click on one of the "Brief" buttons above, the texture rotates by only 1°, and then immediately switches to a new random texture. The tiny 1° rotation is perceived as a much larger jump, reported by most observers between 10° and 60°. Although the amplitude of the jump is highly amplified, its direction is always the same as that of the tiny rotation that preceded it. The same sequence can been seen in slow motion by clicking on the "Brief (slowed down)" buttons. On the other hand, if the preceding rotation last longer, the jump is in the opposite direction, as can be seen by clicking the "Long" buttons.