PRETTY! No, wait, UGLY!

(This is a guest post from our very own Chris!)

The other day I asked eminent commenter and Jaybird’s better Maribou for book suggestions for my son, who likes science fiction and post-apocolyptic stuff, but who, umm… isn’t particularly motivated to find books he likes. Among her recommendations she included the Uglies series by Scott Westerfield, the first two books of which are titled Uglies and Pretties. That reminded me of a visual illusion (everything reminds me of a visual illusion), so I thought I’d share it with you. Stare at the cross in the middle of the video screen, and press play, then prepare to be amazed and horrified!

If you’re wondering why this happens, it’s likely pretty simple. For obvious reasons we’re really, really good at recognizing faces, which means we’re able to process them in a lot of detail, simultaneously analyzing the features (like noses, mouths, eyes, etc.) and their relationships to each other (like how far apart the eyes are). The problem with continually analyzing things really fast in a lot of detail is that you have to rely on some pretty inflexible algorithms, which means that it’s going to be pretty easy to trick them. In this case, it appears that by quickly changing faces as we’re processing the relationships’ between features, the features of the new face and their relationships get all mixed in together with the features and relationships of the first face, and then things get all distorted and trippy. Suddenly George Clooney looks like he’s melting, and Liv Tyler looks like Steven Tyler.

Read more about the illusion from its discoverers here.


Jaybird is Birdmojo on Xbox Live and Jaybirdmojo on Playstation's network. He's been playing consoles since the Atari 2600 and it was Zork that taught him how to touch-type. If you've got a song for Wednesday, a commercial for Saturday, a recommendation for Tuesday, an essay for Monday, or, heck, just a handful a questions, fire off an email to


    • Yeah, that’s almost certainly the same thing happening. It’s trippy.

      Also, for both you and zic below, this video doesn’t bother my eyes at all. I wonder why that is.

      • Do you get migraines? I do, and zic gets them bad. Could be related, either via the brain or via eyestrain.

        • No, I don’t, and I don’t know much about the neurology of migraines, but I imagine that could be it.

      • There’s a part of the brain in the fusiform gyrus responsible for this boggle. At first the neuroscientists thought it was just for facial recognition but it seems to be specialised to all things familiar.

        • Interesting.

          I pay a lot of attention to the difference between my straight-on vision, which can be quite trippy on some days, and my peripheral vision, the peripheral often identifies correctly what’s distorted/warped by the inflammation in the brain causing my ocular migraine.

          Yet it’s hard to really look at something form the side, at the same time; to see it distinctly; it’s much easier to see motion there, the frog-eye bug detector is acute and also useful for spotting shooting stars. I’m recognizing what I see from clues, yet it’s much more accurate then normal ‘seeing’ when I suffer severe migraine.

          Which all leeds to vision as a complex process, much more then simply detecting light with the eye; a complex recognition system that (in my case) can be easily screwed up. Which has me wondering how it is that different ways of using my eyes (center of the field vs. edges of the field) feed information differently.

          • that’s actually pretty easy. Your color vision comes from your central eyesight (cones). You have rods everywhere else, and they are what senses movement.

            … I might suggest turning down the lights. Like, way way down (crescent moonlight levels). That might help reduce the amount of input on your straight-on vision, and with decreased processing you might be able to decrease the trippiness (or, alternatively, recruit other parts of your brain to “reprocess” it for improved understanding).

        • You’re right, it turns out the neurological picture of face perception is a bit more complex than the fusiform face area. There are several other areas that are “face-selective” within the temporal and the occipital lobes. In fact, there may be as many as 8 “face-selective” areas in the ventral and lateral portions of the temporal lobe alone, which, along with the occipital regions gives us two within the fusiform gyrus, one sometimes called the “occipital face area” which is directly adjacent to the fusiform gyrus, the superior temporal sulcus, the anterior and posterior temporal face patches, parts of the occipitotemporal sulcus, parts of the inferior occipital gyrus, and more (there even appear to be faced-tuned areas in the amygdala, which is sort of like the emotional hub of the brain). It’s likely that each of these regions helps with object recognition generally as well as responding to faces specifically, but also that they work together with the rest of the visual cortex as a “face network” to continually produce holistic and dynamic representations of faces, including information about identity, gender, mood, gaze direction, and perhaps even intention. Though what it does best is make for cool visual illusions.

          • Blaise, that’s a pretty cool study. I hadn’t read it until just now, thanks.

            I’m pretty sure what’s going on in this case, and the mirror case that Glyph linked, is just a part-whole processing issue (something similar to what happens with the Margaret Thatcher Effect), but no one’s done the research yet and I’m not a vision person, so I don’t know for sure.This illusion was discovered by accident by an undergraduate research assistant in ’11 or ’12, so it’s really new, at least in this form.

          • Years ago, I had the good fortune to fall in with a neurobiologist working on the turtle brain. Seems this one turtle species has two vision systems: one for above the water, another for below. Index of refraction problem. I did some programming for her, learned a lot in the process, tried to stay current on the subject.

            A good deal of the AI I’ve worked on has been in vision systems. Prosaic stuff, really, looking for defects in phone displays, dead pixels and the like. But all the advances in AI come from neurobiology, mimicking what the brain does. Turns out to be the best approach for parcelling out functionality, not only to discrete tasks but to integration tasks.

            Facial recognition is one of the first tasks assigned to the human brain, learning to identify our caregivers, process their responses to us. Lots of that task is also geared to our own self-image, learning to please caregivers, affection. As the robots grow up, they’ll be assigned the same set of tasks. And my guess is, they’ll be organised along the same lines as our own brains and minds.

          • Blaise, have you seen the studies on facial recognition in other primates? Turns out, even monkeys fall victim to the Margaret Thatcher Illusion, or at least a monkey version of it.

          • AAAAAAAA

            I just looked at wiki for Thatcher illusion.

            I will say that the inverted one does look “wrong” to me, but not as wrong as it does once you turn it right side up, at which point, GOTO line 1.

          • I wrote about that one once upon a time too. It is one of my favorites.

            Also, if you want more visual illusions here, I am happy to post them. I try to recreate them in Gimp all the time, so I might be mildly obsessed.

      • I met some folk who study this at the last MAX conference who were studying this. As I recall their interest started with the Pokeman(?) episode that caused massive #’s of seizures in Japan. We talked for a long time, and my recall is that said some people seek out this sort of visual over-stimulation; almost like they get high off it (my interpretation, not their words). Others, like me, are easily overwhelmed by it. It has to do with our filtering ability, where lack of filtering can lead to inflammation.

        I was very excited because that they thought they could make glasses that would filter out (compress) flickering light for sensitive people. That would mean I could, for instance, go to shows that involve light as part of the performance. I can’t right now. Very sad, that.

        • Blublockers seem like they’ve come a ways style-wise:

          A while back there was some thought that blue wavelengths might be triggering, which tracks nicely with my anecdotal experience with fluourescent lights. So of course, since it fits with my anecdata, it must be true! 😉

          • True for you.

            For me, it’s the fluctuation. Oddly, I’ve recently had mechanical sound (the blinker in a car, for instance) also cause optical migraine. Makes me feel like the walls in my brain are breaking down, and not in a good way.

        • Migraines are the brain malfunctioning. I get severe headaches, but they’re muscular-related, so at least I don’t have to stop eating chocolate.

  1. Ain’t no way to hide your lying eyes.

    (this is really interesting. It’s also really hard to watch, just a few seconds and I get the symptoms of ocular migraine.)

  2. This freaked me out when I saw it the other day on your blog.

    (Hey, does everyone who’s interested in neuroscience read Chris’s blog? You should read Chris’s blog.)

  3. My daughter read Pretties and Uglies (and Specials, which I think is the third in the series), so I skimmed through them, too. They’re not classic literature by any means, and your son may or may not be attracted to them given that there’s a heroine rather than a hero, but they are decent stories for adolescents, stimulating them–at least ideally–to think about what we do to make ourselves attractive and fit in, how authoritarian conformity can be, and what a person’s real value is or ought to be. A bit schlocky, but good schlock. Hella better than that vampire porn stuff with the girl whose life is worthless without a boyfriend, grr.

    • I bought him Uglies and Pretties, along with the first book in the series that Mike suggested, and the first book in another series that Maribou suggested, so I’m hoping he’ll find something he likes. But I don’t think the heroine vs. hero thing will bother him. He did like the first Hunger Games book.

    • He’s 14?

      The Susan Cooper books (The Dark is Rising Sequence) were beloved by my kids at about 9/11; but I read the books to them.

      When I was that age, I’d already begun reading the Roger Zelazney’s Amber books; and the last book wasn’t published until I was well into my 20s.

      With an the off chance we humans are about to begin mining asteroids, I recommend C.J. Cherryh’s book, Merchanter’s Luck

      • Haroun and the Sea of Stories by Salmon Rushdie. One of my favorite books.

      • Zic, 15. He’d get upset if he saw someone say he was 14, because you know, every year counts!

        Thank you for the recommendations. They go on the list. I’m going to try to get him to read 8-10 books this summer, and so far only have 4, so I will definitely check those out.

        He was severely language delayed when he was younger, so he hasn’t always been a confident reader. It’s only in the last year or so that he’s discovered he actually enjoys it, and I’m trying to turn him into a passionate reader without pressuring him too much.

        • I have a similar story.

          I read to my kids throughout high school. If he’s into it, and you can spare the half hour it requires on a daily basis (or near daily) it’s really helpful; particularly for the beginnings of books. I found that once my kids had bought into the story, once they heard the writer’s voice in their ear, it was easier for them to take over and finish the book on their own. Frequently, they wanted to finish reading on their own, my out-loud pace was too slow. I sometimes had trouble getting ahold of the book in question to finish it myself. I’m still catching up on a few of the more memorable unfinished books.

          The art of reading out loud, the sharing of story, the family discussion about story we all heard at the same time; these things are like our evening meals; the highlights of our family life. We still share the meals as often as we can; but the shared reading has slipped away. I miss it, and would have us read together again if I could.

          • OK, that is a friggin’ excellent suggestion. I’m going to try it this weekend. Thank you!

    • “My daughter read Pretties and Uglies (and Specials, which I think is the third in the series)…”

      How has Glyph not made a comment about The Specials, yet?

      I’m a little diappointed in that boy.

      • He’s still trying to work up a good Psychedelic Furs joke.

        • I just came from a PETA meeting, there are no good Furs jokes. They also don’t appreciate you parading your enormous phallic symbol around like that.

          I like the Specials a lot, but I was more of a Madness and (especially) Beat man.

          I actually have a post on first-wave Jamaican ska (the OG stuff that Specials and Madness and The Beat drew on) in the hopper. Stay tuned!

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