Before you read on, look for toothbrushes in the photo above. Find them? Both of them? If you’re like the vast majority of people, you honed in on the one near the sink, but probably took a moment or two before seeing the other, much larger one hanging on the wall. Although it is technically much more visible and not out of context, for a while at least, your brain excluded that enormous blue toothbrush in your visual search.

As it turns out, size matters. When we search through scenes for a particular object, we often miss even giant targets when their size is inconsistent with the rest of the scene. That’s according to scientists at UC Santa Barbara, where this curious phenomenon is being investigated in an effort to better understand how humans conduct visual searches.