The outside world appears to us, immediate, in detail, and seemingly without any effort. We generally don’t question that this is the actual world we live in. However, what we see depends on what we know and what we are searching for.
For example, when looking at the neighboring image, you might just see a bunch of colored lines. If you now search for the yellow line elements, you will find them all within an instance, and see that they form a circle. Similar, if you pay attention to the curved line elements, a rectangle will 'pop-out'.
This illustrates how our perception is an active process that relies on what is relevant for us at a given moment in time. In our lab, we seek to understand the neuronal mechanisms supporting this process. We're mainly using three-photon imaging in macaque monkeys that are trained to perform visual search tasks, like finding a yellow circle.