Cognitive Daily reports nearly every day on fascinating peer-reviewed developments in cognition from the most respected scientists in the field.
Humans are exceptionally good at recognizing faces they've seen before. It doesn't take much study to accurately recall whether or not you've seen a particular face. However, this pattern breaks down when faces come from unfamiliar races. A white person who lives primarily among other whites will have more difficulty recognizing Asian faces, and vice versa.
But how engrained is this difference? How much experience with other-race faces do we need to have before we can recognize them as well as same-race faces? Is learning to recognize other races as difficult as recognizing any new category of objects -- cars, say, or birds? When we do learn to recognize other-race faces, do we really know them as well as more familiar races?
While it has been known for some time that we can learn to recognize other race faces as well as our own, this last question hasn't been studied as thoroughly. Maybe in more difficult tests of recognition, we wouldn't do as well with different-race faces.
To explore this question, a team led by Elinor McKone developed a clever set of three experiments. In the first experiment, white Australian students were exposed to 32 different faces -- some white, and some Asian -- for three seconds each. After a brief break where they were distracted with multiplication problems, they were tested on a set of 64 pictures -- 32 they had seen before, and 32 new pictures. Their job was to say which were old and which were new. As expected, the students were significantly more accurate with same-race faces compared to different-race faces. This showed that with brief exposure, different-race faces aren't recognized as well as same-race faces.
Next, a new group of 23 students was trained extensively to recognize 6 pictures: three white faces, and three dogs. The pictures were only subtly different, as you can see here:
The students were required to be highly accurate -- nearly 90 percent correct -- for both faces and dogs -- this took hundreds of trials. Even when the pictures were shown upside-down, respondents had to be able to accurately identify each face and dog.
Next the test was made more difficult. Viewers had to focus on the center of a computer screen, and images were flashed for 150 milliseconds, again either upright or inverted, at varying distances from the center of the screen. Since the pictures were flashed faster than eyes can react and refocus on a new spot, viewers had to rely solely on peripheral vision to identify the pictures. Here are the results:
So after extensive training, there's a big difference in the results for faces and dogs: With upright faces, viewers were significantly more accurate than inverted faces, but with dogs the situation was reversed and viewers were actually slightly (but significantly) more accurate recalling inverted dogs. This shows that there's something different about how we learn faces than other objects.
In the final experiment, 48 white students were trained to recognize four "friends," selected from the initial set of 64 pictures in the first experiment. The friends matched the gender of the viewer, and each viewer's friends were all the same race -- either white or Asian.
The training again consumed hundreds of trials, and only when viewers were very accurate were they allowed to move on to the test phase (in fact, over half the participants were rejected because they never attained sufficient accuracy). They were tested in the same manner as experiment two, with images displayed at varying differences from the center of the screen. Here are the results:
This time, there was no significant difference in the results for white faces and Asian faces. In both cases, when the faces were displayed upside-down, accuracy was significantly lower than for upright faces. The results for Asian faces were similar to the results for same-race faces in experiments 1 and 2, and different from the results for Asian faces and dogs in those experiments.
In other words, memory for different-race faces can be trained to work in the same way it does for same-race faces, even in a difficult peripheral-vision test, in a relatively short period of time. It doesn't take years of immersion in a foreign culture, just an hour or so studying pictures (albeit hundreds and hundreds of them!).
This suggests that humans have a general pattern for recognizing faces that is adaptable even to unfamiliar faces. McKone et al. argue that we recognize same-race faces holistically, instead of feature by feature. Initially when we see a different-race face, we attempt to remember it using individual features, much the same we remember a animal or other object. But after some training, we learn to recognize even different-race faces holistically, which can be more accurate, but which doesn't work as well when faces are upside-down.
McKone, E., Brewer, J.L., MacPherson, S., Rhodes, G., Hayward, W.G. (2007). Familiar other-race faces show normal holistic processing and are robust to perceptual stress. Perception, 36(2), 224-248. DOI: 10.1068/p5499
Comments
Nice review!
I wonder what the implications of these findings would be for theories on ethnic exclusionism. The contact-theory predicts that people who are confronted with people from a different ethnicity will at first hold a negative attitude towards them, but when `enough' people from a different ethnicity live in the surroundings of a person, his or her attitude will become favorable. Empirical findings have been (somewhat) favorable for this theory.
The interesting question regarding the combination of both types of findings would be: does facial recognition lead to more favorable (ethnic) attitudes?
Would be worthwhile to find out, I'd think ...
Posted by: Rense Nieuwenhuis | April 29, 2008 4:39 PM
This reminds me of my initial experience in the Salt Lake City where every white person looked the same. And I thought it was just the jet lag :)
Posted by: Biswajit | April 29, 2008 5:44 PM
Very nice review, and a well designed experiment. It seems to be part of a trend toward studying perceptual plasticity in social situations. I agree with Rense that there could be interesting follow up experiments to test how this perceptual training actually affects social attitudes. The one that strikes me is likelihood to stereotype: a subject might be more likely to stereotype if he or she cannot recognize differences between individuals of an ethnic group.
But I also appreciate that this research undermines the tendency to say that, because we're better at recognizing faces of our own race, we 'inherently racist.' This explanation -- no, we're better at recognizing faces like the ones we see a lot of the time -- is both less socially pessimistic and more plausible neurologically.
Posted by: Greg Downey | April 29, 2008 6:44 PM
I'm a little bit skeptic about the experiment. When I looked at the dogs, I differentiated the photos based more on leg placement in the photo than on characteristics of the actual dog. I wonder if I'm the only one, or if participants of the study did likewise. I would argue that leg placement is easy to recognize whether a photo is right-side up, upside down, sideways or inverted. Facial characteristics on the other hand are harder to perceive when the photo is angled. I would like to see the study re-done using perhaps 10 photos of each person and 10 photos of each dog and testing for recognition of the same specimen from differing photos. After all... in real life our brains must adjust to seeing the same person with many different expressions and from many different angles. I think that would give more credible results for both sections of the study.
Posted by: Todd Isler | April 29, 2008 7:32 PM
Fascinating!
Have there been studies that examine whether non-human animals have similar highly accurate recognition mechanisms for their own species? Crows come to mind... I imagine some other animals, like mice, probably rely on scent as much as or more than visual cues.
Posted by: Jeannie | April 29, 2008 7:36 PM
I'd say this is not unexpected. It's a common experience of westerners who move to Asian countries. After a while you get much better at recognizing faces, and after some months you even become reasonably good at distinguishing nationality. Chinese, Koreans, Japanese and Thai for example all begin to look noticeably different. There's some website somewhere that has a self-test for this.
Posted by: JM | April 29, 2008 7:53 PM
I think this study clearly demonstrates that we tend to filter out those not automatically classified as potentially part of our immediate social groups. Whether we are culturally isolated from people with different skin color or facial features because of long-standing historical racism or not doesn't necessarily reflect inherent personal racist tendencies, but simply a neurological process adapted to what we're familiar with. I agree that these results are optimistic about the plasticity of culture, although the fact that they had to disqualify so many participants for never achieving high accuracy is a bit disappointing.
It would be interesting to study this in real life to see if it correlates. Certainly a college setting where people of different backgrounds come together on one campus would be the perfect place to do it. Like a "Real World" for face training. haha
Posted by: bg | April 29, 2008 9:03 PM
My experience of living in Asia for 15 years is that, not only is telling Asian faces apart fairly easy, it's now much harder for me to tell white people apart... and I'm white.
Posted by: robin | April 29, 2008 9:49 PM
maybe it's just me, but am I the only one who noticed that the, uh, "angle of the dangle" as it were, was significantly different between the 3 dogs? would the results be the same if we had genitals to go along with the human faces as well? :)
Posted by: ssd | April 30, 2008 4:22 AM
I just thought I'd throw in something fun and semi-related. I'm going to point the folks at that website over to this blog entry, too.
Here: http://alllooksame.com/
Posted by: Katy | April 30, 2008 8:44 AM
It makes sense if you think about it. Works the same way as accents. If you're unfamiliar with particular accents you hear only the major features of the accents. Different but similar accents aren't differentiated. On the other hand, people who've grown up around a particular accent will hear the differences in another accent, not the similarities.
Americans: Can you tell the difference between the Australian and the New Zealand accents? Brits: Can you tell the difference between an American accent and a Canadian one? (Almost) Everyone: Can you tell the difference between the Yorkshire and Lancashire accents?
Why should visual recognition be any different from aural recognition?
Posted by: SimonTeW | April 30, 2008 8:52 AM
Given that only half of the subjects ever reached sufficient proficiency to move to the test portion, doesn't this weaken the conclusion a bit?
Posted by: majolo | April 30, 2008 12:45 PM
I live in a pretty white area, but after spending a couple weeks in Tokyo (also a pretty racially homogeneous place, just a different race than my own), I picked up some skill in differentiating between Japanese faces. Growing up, a lot of older white people joked that "Orientals" all look the same, but I'm sure they'd say the same about us Polacks :)
Funny you bring up accents, SimonTeW. I was just saying the other day that I think I can pick out the difference between an Australian and New Zealand accent now, having listened to Peter Jackson, Fran Walsh, Peta Wilson, Lucy Lawless, etc. and compared it to all the Australian celebrities I'm slightly more familiar with. Haven't had a chance to test it, though.
Posted by: Dread Polack | April 30, 2008 5:23 PM
I noticed this in my own life. When I began the process to adopt a child from China, I began to look at pictures of children differently. I read books, watched movies, made friends with families who adopted at the same time or after I did. The same things happened when I adopted another daughter from India. A few years later when they started school, I was horrified to find that I couldn't tell their white classmates apart.
Posted by: Miss Cellania | April 30, 2008 6:36 PM
I was raised on a ranch. Any rancher can immediately recognize every animal they own. The really good ranchers can recognize all the individual animals for miles around. I've seen them do incredible feats of recognition. This is one reason I became a biology professor rather than a rancher. We had 350 sheep, and they all looked the same to me, except the one black one.
Posted by: Jim Thomerson | May 1, 2008 5:52 PM