I just saw this picture puzzle, and found it easily by doing a row-by-row scan, but it seems harder to find it just by looking around. I was thinking that the puzzle was intentionally designed to draw attention away from the correct location, by the following features:
- Every snowman is different and its nose points in an apparently arbitrary direction, so as to prevent any uniformity that would give the panda away.
- A sizeable fraction of the snowmen have extra things like scarves, hats, bow-ties and and even candy sticks, most of which are also brightly coloured. These distract the viewer as they automatically spend more time looking at these oddities, especially those with patterns. (Saccades tend to concentrate about them.)
- The panda ears are almost the same size as the buttons on the chest of each snowman, and the snowmen themselves are positioned such that many of them have their buttons appearing just above the snowmen in front of them at about where the ears should be.
So I was wondering what are the psychological processes that facilitate such visual misdirection. Is it just the saccade mechanism? My second question is whether there are more convincing examples. For other kinds of visual illusions there are plenty of unambiguous examples, but this one does not feel like an illusion as the task is just to find something.