Prosopagnosia is an impairment of one's ability to recognize faces. This interview with one person with face-blindness is fascinating top to bottom.

What problems does it cause?
The issue is how I remember faces. It doesn’t matter if I know the person: I’ve walked right past my husband, my own mother, my daughter, my son, without being able to recognize them.

It can be very embarrassing, and it can offend people. I once had to drop a sociology class, because I told the professor, to her face, that she was a horrible lecturer. I thought I was complaining to a fellow student! It’s as if I have a missing chip — you feel like you’re just not trying hard enough. Faces are so important to humans that we have a special part of our brain dedicated to recognizing them. Most people remember them as a whole piece, but I don’t.

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To tell people apart I have to find a distinguishing feature. And context is huge. If I’m expecting to see somebody, I’ll figure out who they are by observing their body language, listening to their voice. Good-looking people are the most difficult to recognize.

Is that because their faces are symmetrical?
Yes! Straight teeth, noses within regular limits … everything is so … normal! It’s like a flock of chickens. So what I do is look for specific features. I have one friend who’s average height, middle aged, and white, and she works in an office full of average middle-aged white ladies. And even worse, it’s a doctor’s office, so they are all wearing scrubs. If I meet her at work, I can only recognize her if she smiles — it’s very specific. But these are the things I look for: Some people have a distinctive nose; some people have two different-colored eyes.

I had no idea Chuck Close suffered from prosopagnosia, and now I see so much of his work in a new light.

This is one area where some technology like Google Glasses could really help.

I have problems watching a lot of films and TV shows because everyone looks so perfect I can’t follow the plot. I have a face-blind friend who used to work at the Beverly Hills Whole Foods. His employers loved him because he never recognized the famous customers.

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Can you recognize yourself?
Not always. I’ve had to say to friends of mine, “Is that a picture of me? Who is that?” If I unexpectedly see myself in a mirror, I might think it's somebody else. It's like, Why is that woman staring at me? Those times, I’ve been struck by how serious I look.

One of the many interesting ideas to come from this piece is that prosopagnosia can also be seen as a positive, as immunity against our obsession with symmetry as an indicator of attractiveness, or to unconscious racism.

What attracts you to people?
I have a thing for voices and intelligence. While I can appreciate that someone is attractive on an aesthetic level, I don't feel it on that visceral, "Whoa! They're hot!" way. At least not when I first meet them. I really only become sexually interested when I have talked to someone long enough to know them. I would be hard work to date. I met my husband at the university science fiction club. He has an incredible voice — he’s a public speaker, his grandfather was a radio announcer, and his father works in television. And he’s the smartest person I know — he used to teach English literature.