Unbelievers, I have a question if you have the time?

So I was on the divan inside headquarters looking at the Iron Maiden poster hanging on the opposite wall. I noticed the stripes on the skeleton soldier's left sleeve and wondered if the artist redrew the sleeve to add two stripes?

Then I wondered based on the show Brain Games if I could draw just the hem of a skirt and legs would the brain add (see how I put that in there again? Did it make you go back? Have you found your place yet?) add a shadow onto the legs? Then I thought if it does then I wonder if it puts a shadow in that position based on its known light source? What would happen if you had an imaginary lamp would the brain add shadow in the position it would really be in if the source was real? Or does it assume a source? I need to propose an experiment like on Myth Busters.

Tell me what you think. Christians, Muslims and other religions are welcome to answer. thx