Though a face cannot be both symmetrical and asymmetrical, it’s entirely possible for people to find both sorts of faces attractive. It’s also possible to prefer an asymmetrical face over one that is perfectly proportionate. “If you have a very symmetric, very easy to process face, then you have one problem: You won’t be remembered so well,” Claus-Christian Carbon, a professor of psychology at the University of Bamberg in Germany, told Nautilus. The expert pointed to Meryl Streep’s slight asymmetries to explain this theory. “The little imperfections of her face can be [read] as a sign of authenticity,” he added. Her features also make her more distinct, more recallable.
Margaret Livingstone, a neurobiology professor at Harvard Medical School, also explained to the publication that the human brain processes faces holistically, or as a grouping, not necessarily per trait. Additionally, our brains go about this work starting from the left and ending at the right. This means people don’t always spot asymmetries. David Perrett, professor at St. Andrews University’s School of Psychology and Neuroscience, explained, “I think because we are busy processing one side at one time, we don’t notice the left-right differences.”