Need Brain Training?
Our Brain Fitness Questionnaire will help you find your match.

Others Found
Does Ginkgo Biloba Improve...
Although there have been numerous small studies investigating the effects of Ginkgo Biloba on memory, they have generally have been
preview

New Tricks for Your ...
The results of the 7th Annual Best Illusion of the Year are in! The winner: “Silencing awareness of change by
preview

Don’t Relax Too ...
A study showing that people who retire earlier have lower performance on cognitive tests. This is another piece of evidence
preview

SHARE:

Convex or Concave?

To most people, five of these circles look convex. The one at bottom center looks concave. In fact, all the circles are identical. The one at bottom center is just upside down. However, the brain interprets the circles with the darker part at top as concave and the darker part at bottom as convex. This is because the visual system assumes light is coming from above (the sun, an overhead light) and perceives the shape according to that model.