Some extra-virgin olive oil is adulterated with lower-priced, lower-grade oils and artificial coloring along the supply chain without retailers or consumers ever knowing. Matthias Schrader/AP hide caption

itoggle caption Matthias Schrader/AP

The Delboeuf illusion makes one dot appear larger than the other. But they're the same size. Your brain is misled by comparing the dots to the surrounding circles. Washiucho/Wikimedia Commons hide caption

itoggle caption Washiucho/Wikimedia Commons

Chef Jose Andres at his avant garde Minibar restaurant in Washington. Andres' experiments with gelatins have helped make him one of the most innovative chefs in the country.

Jacquelyn Martin/ASSOCIATED PRESS hide caption

itoggle caption Jacquelyn Martin/ASSOCIATED PRESS

The miracle fruit from West Africa has a chemical that binds to and boosts sweet taste receptors in the presence of acidic foods. Courtesy of Keiko Abe hide caption

itoggle caption Courtesy of Keiko Abe