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.

Let’s look at this picture. Here is a father with his daughter. Can you find a banana hiding in this room? This is not an easy puzzle. So if you solve it you are a genius and it means your IQ is higher!

IQ is an abbreviation of Intelligence Quotient. So, OK, but what is IQ? The IQ is a measurement of your intelligence and is expressed in a number. It’s an estimate also, there will always be a given amount of measurement error.

A person’s IQ can be calculated by having the person take an intelligence test. The average IQ is 100 by definition. If you achieve a score higher than 100, you did better than the average person, and a lower score means you (somewhat) performed less.

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.