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LiveScience
Some people are better at recognizing a face. Now a study of individuals who have prosopagnosia, a disorder rendering them unable to distinguish another's mug, suggests a possible cause: a breakdown in a brain pathway used to process faces.
This breakdown seems to occur at different places in people with the disorder: About half of patients are able to recognize faces, but the signal gets lost before reaching the brain's higher-order centers. The other half seem to have difficulty analyzing faces to begin with, the researchers found.
"This is something we don't have a handle on. There are probably lots of different types of prosopagnosia. There are connections between these different areas, and there are a lot of places this can break down or fail to develop properly," study researcher Bradley Duchaine, of Dartmouth University, told LiveScience. "In many cases we don't understand why they failed to develop the mechanism necessary for face perception."
Duchaine brought in 12 people who were born with prosopagnosia and had them look at several photos of faces while their brain activity was monitored with electrodes. The faces included those of well-known celebrities and many people that the patients shouldn't recognize. The researchers compared the brain activities with those of people who recognize faces normally. [ Inside the Brain: A Journey Through Time ]
A normal brain will show certain responses when it recognizes a face. There will be a strong response after 250 milliseconds in one area of the brain that is responsible for analyzing the visual information from a face and making the connection of whether or not that face is familiar. Then, another response occurs in another area at around 600 ms, which connects that face with higher-level processing including specific information you know about that person.
When the prosopagnosia patients didn't recognize the famous faces, the researchers saw a weak-to-no response at 600 ms, suggesting their brains didn't complete the face-recognition circuit. If they did recognize a face (for example, a president who had been in office for a few years or someone with a unique birthmark), their brains looked just like a normal person's; they showed strong reactions at both 250 ms and 600 ms.
Interestingly, half of the patients showed a normal response at 250 ms and half didn't. The group who responded to the famous faces seems to have normal face-processing and memory abilities, but the signal gets lost when connecting to higher-level processing (the event that takes place at 600 ms) so they aren't able to connect those facial features to information about a known person.
"They are recognizing it at 250 milliseconds, but for some reason that information isn't passed along to those processes that are producing the 600 millisecond response," Duchaine said. "You might imagine there is some kind of disconnection between these [brain] areas, but we don't know what the problem is there."
Recent studies have found that this trait is inherited in families : If your parents are good at remembering a face, you probably will be too. People can also develop prosopagnosia after an accident or stroke in their temporal lobe, which damages the facial recognition centers. Duchaine studied only people who were born with the inability, though.
In contrast to prosopagnosia, some people can remember faces of people they met years ago and only in passing. The " super-recognizers," as they're being called, excel at recalling faces and suggest that there is — as with many things — a broad spectrum of ability in this realm.
Jia-Liu, a researcher at Beijing Normal University in China who wasn't involved in the study, said the study was very interesting. "This study is also important because this marker may be used in diagnosis of prosopagnosia and other cognitive disorders with deficits in face recognition, such as autism," Liu said.
The study was published Jan. 23 in the journal Brain.
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I don't remember faces well. It's embarrassing. I've actually gone on a first date to a restaurant, gone to the ladies room, and had a hard time recognizing my date when I returned. I learned to make a mental note of where the table was located so I wouldn't humiliate myself and offend my date.
However, I'm an Empath. I can tell total strangers a lot about themselves and their private feelings, just by standing close to them.
I wonder if the two are connected in some way.
I'm the same way. I hate it. (For me) it doesn't seem to help much in the context of this society if I can understand how someone feels, but I can't recognize them. Usually I can recognize people if I see them in the same place several times, and then only in that place (for example, a classroom). I would do the same thing you do (on a date) if in that situation. I have the same problem with directions, so I wonder if those two are linked.
Hah, it would be funny testing me with celebrity photos. I don't really follow the movie/tv/music scene, or really pay attention to pop culture at all.
I'm really not good with faces in general. I depend on a lot of cues to recognize people, including body shape, hair (including facial hair), the way they move, and voice. If you strip all of those things away and just show me the 3d contour of their face, I'd be almost hopeless.
I've had trouble picking out my own wife when she is wearing clothes I've never seen her in, and with a hairdo she's never worn before (this happened once when she was performing at a festival, and she came over between numbers, and I almost didn't cue in to her voice and mannerisms fast enough). When my daughter was wearing a swim cap, and an identical suit to the other girls, I had trouble picking out from the crowd at the swimming pool.
I have a mild form of this, too. It's very embarrasing at times.
Are they testing people's ability to respond to famous faces only, or does this inability extend to family members and such? It would be truly problematic if a person could never discern facial features among people in their daily lives. But not being able to tell apart strangers, new acquaintances, or even celebrities that one doesn't often watch isn't that surprising at all. I sometimes watch a movie and find that some actors look so similar the first time through that I can't keep track of who is whom.
And that study only analyzed whether an individual should be familiar or not. What about specific traits that make a person more or less easy to recognize? People tend to find cross-racial identification more difficult, especially if they are not accustomed to seeing a particular race. Would that too be a form of prosopagnosia, or does that condition require a person to literally never be able to recognize any face at all?
MSpielman, I just read a book called "You Don't Look Like Anyone I Know" about a woman's journey of discovery about her own face blindness, and the difficulties you describe are really similar to the ones she talks about. Seeing people out of context (where she would expect to see them or in different clothes or haircuts or whatever cause her a lot of problems too. Visual cues (besides the face) are essential to identifying people for those suffering with this disorder.
Visual cues (besides the face) are essential to identifying people for those suffering with this disorder.
At least from what I read in this particular book. :)
I dislike the term "face blindness". Before I knew it existed in a medical way, I've always called it "face dyslexia". I am not blind to peoples faces, they just don't "gel" in my brain, similar to what I think happens to dyslexic people. And for me, there is a repeatability quotient. Once I see people I have a hard time recognizing, I will finally start to recognize them after about the 20th time of seeing them, as long as they are in the same environment and hair style. I could not distinguish the difference between Monica and Rachel on Friends for the whole first season!
The first time watching Lord of the Rings, despite knowing the story inside and out, I had trouble telling the difference between Aragorn and Boromir. They both had similar hair and beard styles, which are normally my big cues. I was fine if they were talking, or when it was a clear plot moment for one of them. But action scenes, I had trouble.
I believe I have a mild form of this. It actually has made it hard for me to get to know my neighbors in my urban neighborhood...I need more repetition than a lot of people before I remember a face, or need to have a conversation (context) to tie it to. I find people remember me better than I them.
So when someone says "wow, I didn't recognize you with that hairdo", they may literally mean it? Interesting.