A really good example of this effect can be seen in Adele's "upside down face" album cover – shown in both orientations (currently!) here: https://duckduckgo.co

A really good example of this effect can be seen in Adele's "upside down face" album cover – shown in both orientations (currently!) here: https://duckduckgo.com/?q=adele+upside-down+allbum&atb=v225-1&iar=images&iax=images&ia=images https://duckduckgo.com/?q=adele+upside-down+allbum&atb=v225-... It's amazing how, despite being completely and utterly non-normal the right way up, it looks fine rotated by 180º and your brain just fills in the blanks quite happily.