Faces on the brain
The brain has specific areas devoted to the face
When we see a face we can judge almost immediately that person’s sex, age and ethnic origins, and can tell to some extent what he or she is thinking and is like. We can tell if it is someone we have seen before, even if they have aged, changed hairstyle or are wearing new glasses. This ability depends mainly on specific face-recognition systems in the brain.
A dramatic illustration of this specificity comes from people who cannot recognise faces, a condition known as prosopagnosia (facial blindness).
The term was coined by a German physician in World War II who studied patients with brain damage, including a soldier with a bullet wound who could not recognise the faces of his friends and family, or even his own face, but relied on clothing or other cues. People with prosopagnosia can see perfectly well and can describe or draw someone as well as anyone else, but cannot identify someone as a particular individual.
The condition is generally associated with brain damage, though there is some evidence of inherited forms. It is also possible that milder forms are more common than once thought – perhaps explaining why some people have trouble tracking particular characters in films.