The Benussi effect with rectangles?

The perceived depth of the Benussi effect is usually demonstrated by presenting a configuration of nonconcentric circles on a rotating disc. However, in the current investigation with 21 undergraduates the Benussi effect was elicited by presenting an eccentric configuration of rectangles. Depth was reported when the configuration of eccentric rectangles was alternated rapidly and successively with its mirror image. As is characteristic of the Benussi effect, there was an increase in apparent depth with an increase in the eccentricity of the rectangles.