Riddles that challenge us to spot differences between 2 similar images activate our concentration power to the maximum: they put our eyes and brain to work. This is great because training our minds is as important as exercising our muscles. 90 % of viewers can’t spot the mushroom, do you see it?

Sometimes we look at an image and something immediately catches our attention because it is not where it should be. Other times we feel that something is wrong, but we don’t understand exactly what it is and so we have to look more closely.

Then we notice details that we haven’t seen before and find more and more inconsistencies. Okay, that doesn’t usually happen in everyday life, but it does happen in our selection of images with strange errors that are difficult to detect.