Brain teaser: Only those with sharp vision can spot the leaf hidden among the parrots in the picture in 7 seconds?

Optical illusions are mesmerizing, mind-warping images that tax the brain’s ability to deal with reality. They often present things, drawings, or people in ways that cannot possibly make sense, thus raising wonder and interest. From cognitive and physiological to physical illusions, these visual tricks have been a subject of psychoanalysis for years, shedding light on how we perceive our surroundings.