does anyone know which part of the brain is responsible for helping us see images into fluid motion? when Ive experimented with dextromethphan(an otc drug used for coughing, i used it recreationaly, it is a dissociative drug that has effects that are similar to ketamine) in my younger days i use to notice that when i waved my hand in front of my face i would see images of my hand instead of seeing it as one fluid motion.