Look Who's Talking

The exhibit can be perceived either as two white faces looking at each other with a black background, or as a black vase on a white background. When we pushed the button, the persons appear to be talking to each other.
This exhibit is classified as figure-background illusion. The shape of the figure depends on which side of the outline is regarded as a part. The changes in the figure that we saw may be due to our shift of attention on the shape of the outline. Our experiences and interests can influence how we perceived the figure. This would affect our inclination as to which side of the outline should be given emphasis.