How do you turn pretty girls into ugly trolls without make ups or special effects? All you need is some good ol' optical illusion. Here's the Flashed Face Distortion Effects:
Like many interesting scientific discoveries, this one was an accident. Sean Murphy, an undergraduate student, was working alone in the lab on a set of faces for one of his experiments. He aligned a set of faces at the eyes and started to skim through them. After a few seconds, he noticed that some of the faces began to appear highly deformed and grotesque. He looked at the especially ugly faces individually, but each of them appeared normal or even attractive. We called it the “Flashed Face Distortion Effect” and wanted to share it with the world, so we put it on YouTube.
The effect seems to depend on processing each face in light of the others. By aligning the faces at the eyes and presenting them quickly, it becomes much easier to compare them, so the differences between the faces are more extreme. If someone has a large jaw, it looks almost ogre-like. If they have an especially large forehead, then it looks particularly bulbous.
See it for yourself in this video clip:
http://mbthompson.com/research/ | YouTube Link - via The Presurfer
Now, for those who do not like my saying it, but would prefer something a bit more technical and "formal". Here is a segment from "Consciousness as Integrated Information: A Provisional Manifesto" by Neuroscientists Gerald Edelman and Giulio Tononi
The IIT claims that, just as the quantity of consciousness generated by a complex of elements is determined by the amount of integrated information it generates above and beyond its parts, the quality of consciousness is determined by the set of all the informational relationships its mechanisms generate. That is, how integrated information is generated within a complex determines not only the amount of consciousness it has, but also what kind of consciousness.
Consider again the photodiode thought experiment. As I discussed before, when the photodiode reacts to light, it can only tell that things are one way rather than another way. On the other hand, when we see "light," we discriminate against many more states of affairs, and thus generate much more information. In fact, I argued that "light" means what it means and becomes conscious "light" by virtue of being not just the opposite of dark, but also different from any color, any shape, any combination of colors and shapes, any frame of every possible movie, any sound, smell, thought, and so on.
What needs to be emphasized at this point is that discriminating "light" against all these alternatives implies not just picking one thing out of "everything else" (an undifferentiated bunch), but distinguishing at once, in a specific way, between each and every alternative. Consider a very simple example: a binary counter capable of discriminating among the four numbers: 00, 01, 10, 11. When the counter says binary "3," it is not just discriminating 11 from everything else as an undifferentiated bunch, otherwise it would not be a counter, but a 11 detector. To be a counter, the system must be able to tell 11 apart from 00 as well as from 10 as well as from 01 in different, specific ways. It does so, of course, by making choices through its mechanisms; for example: is this the first or the second digit? Is it a 0 or a 1? Each mechanism adds its specific contribution to the discrimination they perform together. Similarly, when we see light, mechanisms in our brain are not just specifying "light" with respect to a bunch of undifferentiated alternatives. Rather, these mechanisms are specifying that light is what it is by virtue of being different, in this and that specific way, from every other alternative—from dark to any color, to any shape, movie frame, sound or smell, and so on.
In short, generating a large amount of integrated information entails having a highly structured set of mechanisms that allow us to make many nested discriminations (choices) as a single entity. According to the IIT, these mechanisms working together generate integrated information by specifying a set of informational relationships that completely and univocally determine the quality of experience.
Full Text: http://www.biolbull.org/cgi/content/full/215/3/216
"The effect seems to depend on processing each face in light of the others. By aligning the faces at the eyes and presenting them quickly, it becomes much easier to compare them, so the differences between the faces are more extreme. If someone has a large jaw, it looks almost ogre-like. If they have an especially large forehead, then it looks particularly bulbous. We’re conducting several experiments right now to figure out exactly what’s causing this effect, so watch this space!"
I'm trying to say what is causing the effect. It's not a mystery except to those who love mystery.