Our bodies have the ability to quickly recognize events happening around us, such as our rapid fast reactions to a bear attack. The speed at which our brains comprehend and analyze the things we see is astounding.
Whether we know it or not, our peripheral vision is always at work analyzing our visual field. This is called spacial attention. Spacial Attention is the images our brain analyzes even before our eyes move to focus on a specific region. It's why if someone throws a giant rubber ball at our head, we have a split second inclination to move even before we fully see the ball soaring majestically towards us. These rapid responses have probably saved man kind thousands upon thousands of times.
Life motion is another function of our brains to process the things we see. By recognizing specific patterns such as the motion of a human body, or the flow of a liquid, our brain instinctively gives us an immediate idea of what we are seeing. So at night if I see to globes of light moving towards me, I would naturally be inclined to think a vehicle is barreling at me.
I personally experience this when I awake at night because the outline I can see of my backpack looks like a hunched over old man. So I go "Ahhh, there is an old man in my room!", but in actuality its just my perception based on the generic shape. Without detail in an image our brain fills in what we are seeing.
This raises the question of how our minds direct these intuitions and what objects we choose to identify with. Like human motion in a series of dots, demonstrated in lecture. Do we identify something because we see it in a large magnitude, or because its something we saw early on in our lives? So it acts as like a reference point? It would be interesting to see what various people see, within certain random objects, similar to a Rorschach test.