I read an article by Carl Zimmer in the latest issue of Discover Magazine about research into how the brain recognizes faces. Just like all investigations into the human brain and vision, this one turned up completely unpredicted results.
Human brains contain a kind of average face template, and for each real face we see, we register how it differs from average. Is this face longer than average, wider than average? Is this nose narrower or wider or shorter or more bent than average? Are these ears bigger or more or less protruding? And so forth.
When we recognize a friend or a relative, we are remembering the idiosyncrasies of their features compared to the visual face templates in our brains. Zimmer points out that this is why caricatures work so well. The caricaturist exaggerates any facial idiosyncracies (as well as body idiosyncrasies) and we instantly recognize George W Bush or Barack Obama.
We couldn’t have predicted how our brains make social recognition possible. This part of the human visual system evolved over eons, starting with primate ancestors. We primates are social species, and our survival requires us, in part, to recognize one another as friends, relatives, or strangers. Our visual face recognition equipment evolved using reptilian brain parts that were already in place doing other jobs, or similar jobs for different purposes.
In the last couple of centuries, research uncovered a number of surprises about vision and the human brain. The visual part of the brain is in the back, even though our eyes are in front. We see and recognize objects using very little visual detail; but only certain details, such as edges, are useful. Our brains are determined to make sense of what we see, and will tell us fairy stories rather than just say they don’t recognize what our eyes have delivered.
Getting back to faces, many years ago I read an article about facial beauty. The author of that article had discovered that humans judge faces as beautiful if they are symmetric, the more symmetric the more beautiful. In other words, according to the Discover article, we seem to think the average face template in our brains is the most beautiful of all.
So instead of the eye of the beholder, perhaps beauty is in the brain of the beholder.