Click on the picture below and figure out how the girl spins? Answer by posting a comment, add also what your job or field of expertise is. According to an article in an Australian news site people seeing the girl spin clockwise use their right brain half and if they see her spin anti-clockwise they use the left brain half.

Me and my colleagues are engineers so we should be pretty "left brainy" but we all saw her spin clockwise so I do not really believe in the article. I could see her spin anti-clockwise too when looking at her shadow for a while imagining she is turning the other way and then looked at her, try it and will blow you away. This shows that we humans do not sense the reality but what we perceive as the reality.