For years, the spinning dancer optical illusion has been making the rounds — usually with some text suggesting that if you see the girl spinning clockwise, you’re right-brained (more creative), and if you see it moving counter-clockwise, you’re left-brained (more logical).
But a psychology professor says that right-brained/left-brained stuff is hooey — and isn’t what the illusion was ever really about.
Spinning dancer silhouette illusion
A psychology professor has found that the way people perceive the silhouette illusion, a popular illusion that went viral and has received substantial online attention, has little to do with the viewers’ personality, or whether they are left- or right-brained — despite the fact that the illusion is often used to test these attributes in popular e-quizzes.
Nikolaus F Troje, PhD, says that a reported preference for seeing the silhouette spinning clockwise rather than counter-clockwise is dependent upon the angle at which the viewer is seeing the image.
“Our visual system, if it has a choice, seems to prefer the view from above,” says Dr Troje. “It’s a perceptual bias. It makes sense to assume that we are looking down onto objects that are located on the ground below us rather than floating in the air above us.”
In the silhouette illusion, created by created by web designer Nobuyuki Kayahara, a silhouetted woman is seen spinning on one foot, her leg extended. The appeal of the illusion is in the way the woman is spinning — she can be perceived as spinning clockwise or counter-clockwise.
Why the illusion works
Dr Troje and his team found that a view-from-above bias (VFA) is what makes the viewer prone to seeing the silhouette in a certain way, not one’s personality or whether the viewer is left- or right-brained.
When shown the silhouette illusion, the study’s 24 participants most often reported that the woman was spinning counter-clockwise if viewed from above, and clockwise if viewed from below. Thus, the viewing angle causes the difference in perception.
The theory can also be applied to other popular illusions, including a Necker Cube (as seen at right), which is often used in online personality tests.