Posts Tagged ‘Avatar’

“But I thought you were blue!” That’s what Jake Sully, the main character in Avatar, says when he wakes up as an alien at the very end of the movie. Actually, the movie ends just before he has a chance to say anything, but that’s my guess about what he would have said. The question is: Why would he say that? (Or, if you’re a stickler: Why would I say he would say that?)

For those who haven’t seen the film, what you need to know is that Sully is a human who, from the safety of his brain-interface chamber back at the lab, can remotely control a “soul”-less alien body. And, at the end of the movie, and through the miracle of human suspension of disbelief, his human self gets literally uploaded into the alien’s body. Sully thereby becomes a bonafide eight foot tall, blue alien, and in the final frame of the movie we see his alien eyes open.

Question is: What does Sully see when he opens his eyes? And, more to the point: Does his new alien wife still appear blue to him?

By way of answering, let’s back up and remember what visual systems are for. When we look out at our world through our eyes, we implicitly believe we are seeing it as it truly is. Our eyes and visual systems are to us objective scientific measuring devices. But evolution does not select for objective scientific equipment – evolution selects for visual systems that best serve the animal and its reproduction. Although often the best perception is one that veridically reflects the truth, sometimes the best solution is a “useful fiction,” a little-white-lie perception that serves us better than an accurate accounting of the actual.

Consider the accent of your own voice. To you, you have no accent. It is other people that have an accent. And they think it is you that have an accent. Perceived accent, or “accentness”, is not a quality of the speech stream itself. Accentness is not an objective perception of anything out there. It depends on the baseline accent one has become adapted to, namely your own. When one adapts to a stimulus and it becomes baseline, the “qualitative feel” of that stimulus diminishes, i.e., it begins to feel like nothing to perceive it. The benefit of this is that even very  tiny deviations away from the baseline feel perceptually highly salient. Your own accent doesn’t sound accented because it is your baseline accent, allowing you to be trigger sensitive to the modulations around it from the voices of different people and their different emotional inflections. This is also why you don’t notice any smell to your own nose, any taste to your own tongue, or any temperature to your own skin.

And, in addition, it is why you don’t perceive your own skin to be colorey. People perceive the color of their own skin (or that of the most common one in their experience) as uncolorey and difficult to name. This perceptual adaptation to the baseline skin color allows people to be highly sensitive to the subtle color modulations happening on the skin of others as a function of mood or state.

Now we can circle back to our earlier question. When Sully opens his eyes as an alien, does his alien wife still appear blue to him? And the answer is no. He’s one of them now, and will perceive his wife’s skin, and his own skin, as peculiarly uncolorey, no longer blue at all. He will also not notice the taste of his own alien saliva, something you can be sure he would have noticed were he to have tasted alien saliva as a human. And now we see why alien Sully exlaimed, “But I thought you wereblue!” Let’s just hope he wasn’t into her only because she was blue!

Other pieces about color vision and skin are here, and also play prominently in my book, The Vision Revolution.

This first appeared on January 6, 2010, as a feature at the Telegraph.

Mark Changizi is a professor of cognitive science at Rensselaer Polytechnic Institute, and the author of The Vision Revolution (Benbella Books).

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This first appeared on January 2, 2010, as a feature at the Telegraph.

You know what I love about going to see plays or musicals at the theater? Sure, the dialog can be hilarious or touching, the songs a hoot, the action and suspense thrilling. But I go for another reason: the 3D stereo experience. Long before movies were shot and viewed in 3D, people were putting on real live performances, which have the benefit of a 3D experience for all the two-eyeds watching. And theater performances don’t simply approximate the 3D experience – they are the genuine article.

“But,” you might respond, “One goes to the theater for the dance, the dialog, the humans – for the art. No one goes to live performances for the ‘3D feel’! What kind of low-brow rube are you? And, at any rate, most audiences sit too far away to get much of a stereo 3D effect.”

“Ah,” I respond, “but that’s why I sit right up front, or go to very small theater houses. I just love that 3D popping out feeling, I tell ya!”

At this point you walk out, muttering something about the gene pool. And you’d be right. That would be a rube-like thing for me to say. We see in 3D all the time. I just saw the waitress here at the coffee shop walk by. Wow, she was in 3D! Now I’m looking at my coffee, and my mug’s handle appears directed toward me.Woah, its in 3D! And the pen I’m writing with. 3D!

No. We don’t go to the live theater for the 3D experience. We get plenty of 3D thrown at us every waking moment. But this leaves us with a mystery. Why do people like 3D movies? If people are all 3D-ed out in their regular lives, why do we jump at the chance to wear funny glasses at the movie house to see Avatar? Part of the attraction surely is that movies can show us places we’ve never been, whether real or imaginary, and so with 3D we can more fully experience what it is like to have a Tyrannosaurus Rex make a snout-reaching grab for us.

But there is more to it. Even when the movie is showing everyday things, there is considerable extra excitement when it is in 3D. Watching a live performance in a tiny theater is still not the same as watching a “3D movie” version of that same performance. But what is the difference?

Have you ever been to one of those shows where actors come out into the audience? Specific audience members are sometimes targeted, or maybe even pulled up on stage. In such circumstances, if you’re not the person the actors target, you might find yourself thinking, “Oh, that person is having a blast!” If you’re the shy type, however, you might be thinking, “Thank God they didn’t target me because I’d have been terrified!” If you are the target, then whether you liked it or not, your experience of the evening’s performance will be very different from that of everyone else in the audience. The show reached out into your space and grabbed you. While everyone else merely watched the show, you were part of it.

The key to understanding the “3D movie” experience can be found in these targets. 3D movies differ from their real-life versions because everyone in the audience is a target, and all at the same time. This is simply because the 3D technology (sending up left and right eye images to the screen, with glasses designed to let each eye see only the image intended for it) gives everyone in the audience the same 3D effect. If the dragon’s flames appear to me to nearly singe my hair but spare everyone else’s, your experience at the other side of the theater is that the dragon’s flames nearly singe your hair and spare everyone else’s, including mine. If I experience a golf ball shooting over the audience to my left, then the audience to my left also experiences the golf ball going over their left. 3D movies put on a show that is inextricably tied to each listener, and invades each listener’s space. Everyone’s experience is identical in the sense that they’re all treated to the same visual and auditory vantage point. But everyone’s experience is unique because each experiences themselves as the target – each believes they have a special targeted vantage point.

The difference, then, between a live show seen up close and a 3D movie of the same show is that the former pulls just one or several audience members into the thick of the story, whereas 3D movies have this effect on everyone. Part of the fun of 3D movies is not, then, that they are 3D at all. We can have the same fun when we happen to be the target in a real-live show. The fun is in being targeted. When the show doesn’t merely leap off the screen, but leaps near you, it fundamentally alters the emotional experience. It no longer feels like a story about others, but becomes a story that invades your space, perhaps threateningly, perhaps provocatively, perhaps joyously. No, we don’t suffer the indignity of 3D glasses for the “popping out feeling”. We enjoy 3D movies because when we watch them we are no longer mere audience members at all.

Mark Changizi is a professor of cognitive science at Rensselaer Polytechnic Institute, and the author of The Vision Revolution (Benbella Books).

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