011/365 – Tuesday, January 11, 2011
- Keep your eyes fixed on the small white mark in the center.
- At first, the ring is stationary and it’s easy to tell that the dots are changing.
- A few seconds later, the ring begins to rotate and the dots suddenly appear to stop changing.
But play the movie again, this time looking directly at one of the dots and following it as the ring rotates.
You will see that, in fact, the dots had been changing the whole time, even during the rotation—you just didn’t notice it.
This failure to detect that moving objects are changing is also called silencing.
This is an example of silencing, as described in a paper by Jordan W. Suchow & George A. Alvarez published in Current Biology:
“Loud bangs, bright flashes, and intense shocks capture attention, but other changes—even those of similar magnitude—can go unnoticed.
Demonstrations of change blindness have shown that observers fail to detect substantial alterations to a scene when distracted by an irrelevant flash, or when the alterations happen gradually.
Here, we show that objects changing in hue, luminance, size, or shape appear to stop changing when they move.
This motion-induced failure to detect change, silencing, persists even though the observer attends to the objects, knows that they are changing, and can make veridical judgments about their current state.
Silencing demonstrates the tight coupling of motion and object appearance.”
The full set of demos and a reprint of the paper are available here