It’s scientifically proven that, although the brain isn’t really a muscle, it needs the training to stay in good shape. Solving a riddle is a fun way to make your brain think outside the box or sweat with effort.
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.