You can pretty much consider it a law that your cognitive ability improves as you develop from a child into an adult. The usual exception to this is your ability to learn, especially with languages or a musical instrument, where children excel at picking up new talents. But with knowledge, memory, attention, and pretty much all other measurable mental capacities, children are the developers rather than the masters. Well, until one study came along to cast doubt on one aspect of our attentional ability.
Change detection is a popular concept studied in experimental psychology. It refers to our ability to notice differences between images. If you’ve ever tried a “spot the difference” puzzle, you know how tricky it can be to spot small differences between otherwise identical images that sit next to each other. But when you flash two images independently to people, and ask them to report whether there is a difference, it becomes difficult to notice even large changes in the images.
Our general weakness in spotting these kinds of differences is referred to as change blindness. The remedy is focused attention. When a change is significant enough, and there is no interruption in the continuity of images, our attention is automatically drawn to the change. But with interruptions in continuity, or when the change is small, we need to work much harder to focus our attention in the right area. This is why filmmakers often get away with continuity errors between shots or frames. The transitions between shots disrupt the image continuity enough that we miss the errors. Here is a fantastic example of a card trick employing change blindness, so you can see for yourself.
So what does this have to do with children? Researchers decided to directly compare change detection abilities between children (4–5 years old) and adults (~20 years old). Both groups saw cartoon characters that could differ in one of two characteristics (body shape or hand shape). During the main part of the experiment, participants were only asked to look for characters who matched a particular body shape, so their attention was focused on a single characteristic. After the main part of the experiment, the adults and the children saw a range of characters, and were asked whether or not they had previously seen those exact characters. Adults performed just as well as kids when rejecting characters who differed in the characteristic that they focused on during the main experiment (i.e. body shape). But shockingly, the kids were significantly better than adults at identifying characters who differed in the characteristic they did not focus on (i.e. hand shape).
When it comes to detecting visual changes outside our direct focus, children may outperform their parents. It seems that adults have a highly selective focus while children are more diffuse or scattered in their attention. Attention-related circuits in the brain are developing throughout childhood, and it may be that this immaturity in attentional control results in a serendipitous advantage for processing information that is not immediately relevant. So for us adults, our mature ability to zero in on particular visual traits means we are successful in recognizing relevant changes. But when asked about details that are irrelevant to that previous focus, the kids come out on top.