Each year the Neural Correlate Society selects its favorite visual illusions, with a panel of judges narrowing the field to ten finalists and the three overall winners voted on by members of the society. The top three illusions of 2009 are:
1. The break of the curveball (Shapiro, Lu, Knight, Ennis). Compare the trajectory of the ball when viewed directly versus peripherally:
2. Color dove illusion (Barkan & Spitzer). Select a background color and focus on the black dot within the dove. The background disappears, but the color has a lingering effect:
3. The illusion of sex (Russell). A simple change of contrast alters our perception of the gender of this face:
View the rest of the top 10 list here.