You may have heard of a condition called prosopagnosia, or face-blindness. It's when people are unable to recognize or recall people's faces, regardless of how long they've known them. I've suffered from a mild form of this my entire life, but fortunately my affliction is occasional and random. That is, some faces I'll instantly and permanently remember, others take some time to permanently fix in my brain, and other people I could see several times a day but never be able to recall what their face looks like. There's no seeming reason for the discrepancies, but I've noticed trends. I have yet to find an account of anyone who only experiences occasional face-blindness towards certain individuals, so I figured I'd go into detail about what I experience.
Up until a few years ago I didn't know there was a term for this. It was my secret embarrassment that led to a lifetime of awkwardness in school and when meeting new people. I don't know at what age I became aware that I had delays and difficulty recognizing some of my classmates, but usually during the first few weeks of the new school year, if there were new kids I didn't know yet, I had anxiety until my brain finally registered everyone's face. Until that happened, I could never predict whether I'd recognize an unfamiliar classmate the following day.
If the teacher had divided us into work groups earlier that week, and told us to get into groups with our partners, there was always the small chance that I'd have no idea who my partner was. I could look around the room and rule out the people I obviously knew. But if there were a few new kids that year, I might not be able to recognize them yet, and I wouldn't know who I'd sat next to the previous day. But this would only happen if my brain hadn't yet "fixed" the face in my head. Meaning, once I recognize and know someone, they'll never be unfamiliar to me from that point on. It's just that I never know if and when I'll struggle to remember a new face. It's so frustrating and embarrassing that I can't predict when or if this will happen.
As I said earlier, I've noticed some trends but they're not absolute. If I find you very interesting or attractive, I'm almost always able to immediately fix your face in my head, and I'll never forget you. If you are a rather bland and nondescript person (sorry!) I am likely to have trouble remembering your face. And there are a few people who, no matter how hard I try, just look the same to me and I don't recognize them. There have been weeks or months at a time when I couldn't tell two coworkers or two classmates apart, and then when it suddenly hit me and I could permanently recognize them, I couldn't believe it because they didn't look anything alike.
Brains are weird.
(I actually like it when people post lots of selfies from different angles and in different lighting, with different facial expressions. I can study the photos and tell myself "Okay, my coworker Jenn can look like this, or this, or this," and that does help if I'm trying to memorize who Jenn is.)
I do want to make a distinction here for those who are confused by the term face-blindness. I often see it "illustrated" by pictures of gray or blurred faces with no eyes or noses or features at all. This is not how I (or how I believe most people with face-blindness) perceive people at all. We are not literally blind. Our prosopagnosia is not related to a vision disorder, and we see every detail of a face just the same way we see every detail of anything else. What we have trouble with is facial recognition. I absolutely see your eyes, nose, lips, etc. Your face is a normal face. I could have a conversation with you, but if you're a stranger who walked away and came back 20 minutes later, there is a small chance I wouldn't recognize you, especially if you changed your shirt or your hair. Your face just wouldn't register as one that I'd just seen.
Fortunately, this is rare for me, and as I've gotten older I've learned to anticipate the possibility of it happening, so I try to pay more attention to the (for lack of a better word) bland or non-descript people I encounter. That's tough. Most people who have prosopagnosia can never recognize a face, even their family or loved ones; instead they learn to use cues such as hairstyle, voice, etc. And this can throw them for a loop if someone shaves a beard or changes their hair. And people with a severe form can't even recognize themselves in a mirror.
One thing I'd like to point out about myself is that I otherwise have a fantastic visual and spatial memory. I can glance at a map and memorize a route in my head, and recall it days later. I can scan an instructional diagram and then build the thing from memory. I know when something has been changed in my familiar surroundings. I keep dream diaries going back to childhood, and just reading descriptions of dreams I had 25 years ago makes me see them in my mind as if I'm experiencing them again. I can visualize and describe in detail memories of events that happened throughout my life. But for some reason, I blank on random people's faces. I don't know if this is at all related to prosopagnosia though.
Having to fake my way through a conversation with someone who knows me (but whom I do not recognize) was fairly common when I was growing up. Most of my parents' friends looked alike to me and I rarely saw them often enough to pay attention. I know many of them got insulted, and my parents were horribly offended by my seeming lack of interest in their friends. I've never told my parents about my troubles with facial recognition. I've read that it's thought to be genetic, so I wonder if any of my family had it and never talked about it, either.
Interestingly, I've never had any delayed recognition of family members.
The most frustrating thing is that I can't predict how long it will take before my brain permanently registers your face. As I explained earlier, if you're a visually interesting person with distinguishing features, and I'm paying attention, (and especially if I like you or find you attractive), my brain will register your face immediately and I'll never have trouble recognizing you. But if you're sort of plain, I might be unable to recall your face and spend months confusing you with another person. Eventually it will stick in my brain, but the length of time until it sticks is impossible to predict.
This can cause a professional embarrassment as well, especially because I work as a receptionist at an animal hospital. We have a few (human) clients who I still struggle to recognize even when they come in every week. If they come in unexpectedly without their pet (for example, to buy dog food or renew a prescription), I might not recognize them. I've had several clients drop their pet off in the morning and then come to pick them up in the evening, and even though I was the one who checked them in, when they come back I don't know who they are. Sometimes it doesn't matter if they've changed clothes over the course of the day or not. I cover myself by asking "Sorry, how do you spell your last name?" so I can look up their file without revealing that I don't recognize them. I'm getting better, though, because I have to force myself to pay attention to voice, height, gait, mannerisms, etc. But it's always a crapshoot until that day they walk in and all of a sudden I know who they are. There's no sudden "A-ha!" moment, it just...happens.
I am so thankful that my affliction is mild and that I never fail to recognize someone after that point.
Yeah, brains are weird.