Why do we observe patterns if squeeze or rub our closed eyes hard? Surely you’ve noticed such a strange phenomenon, and if not, try to do it now👀 These visual phenomena are called phosphenes. And nope, these are not "residual patterns of what one saw before closing one's eyes." These patterns are the result of excitation of nerve receptors. Pressures on the eyeball cause mechanical irritation of the retina and/or optic nerve. Since the visual centers of the brain are accustomed to interpreting information in only one way, they "draw" a picture before the eyes (most often in the form of divergent circles).