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. Now let’s try this one Can YOU spot the robin in this herd of reindeer?

There are a number of confusing elements to the puzzle, such as reindeers with patterned horns, red and yellow scarves and Santa hates which draw your eye away from the Robin.

The puzzle was created by Focus Clinics, a laser eye clinic in London with a 100 percent 20/20 success rate for all common prescriptions to illustrate how much we rely on our eyes and the importance of keeping them in good health.