The spinning dancer illusion, as seen on the right, was created by web designer Nobuyuki Kayahara in 2003. Because it lacks the visual cues used to determine depth, it can be seen as spinning in either direction.

Around 2007/2008 it was widely circulated as a right-left brain personality test. That the image can serve as a personality test has been dismissed by skeptics, which is reasonable as their is no evidence for the proposition. It would be nice to have a concrete answer though, so, to that end, the illusion was appended to the Big Five Personality Test as a “research item” and people who took the test were directed to indicate which direction they saw the image spinning (or were given the option not to answer).

In this time 934 of the test takers indicated their answers were accurate and suitable for research. The sample is 53% male; average age is 30.0 years; 72.1% saw the dancer spinning clockwise. The differences in their big five personality traits are tabled below.

Trait Average (clockwise) Average (counterclockwise) p extraversion 3.08 3.07 0.84 conscientiousness 3.32 3.47 0.01 neuroticism 2.98 3.09 0.08 agreeableness 3.89 3.89 1 openness 4.08 4.02 0.22

There was one statistically significant difference (p<0.05), conscientiousness, but its effect size was minor. So, yes, the spinning dancer can serve as an indicator of personality, although an extremely minor one and not in a right-brain left-brain sort of way. The data used for the post can be downloaded for reanalysis here.