What type of words serve as the bottom rung, or atomic words, in the lexicon?
The ones that come out from WordNet [a lexical database of the English language developed at Princeton that ranks words from the most basic to the most complex] are words like: abstraction, act, entity, event, group, phenomenon, possession, etcetera.
How does this manner of organization reflect a mechanism in our brain?
My interpretation of this result is that culture has over time evolved the meanings of the words in our lexicon so as to minimize the total size of definitions. And the reason that was selected for was because that way we could all fit more words in the head and have a richer vocabulary.
Does that imply an underlying drive toward efficiency or conciseness?
Sometimes when you speak about evolution, you mistakenly say that evolution is striving for developing a wing. But, it's blind cultural evolution. Over time, meanings of words are going to change. The structure of the lexicon is passed on, generation to generation, there'll be selection pressure changing it in certain ways. Sometimes it will change in ways that are hurtful, making it harder for people to remember. Those will tend to change back over time. So, it's blind cultural selection with no directionality per se.
If the dictionary study involves cultural evolution as its driver, then the new work on the visual system involves natural selection–based evolution. Why is it that we need to "perceive the present," as you put it, or see into the future?
Animals who move or are in a world that moves around them—as long as there are things moving somehow relative to you—will be selected to have perceptions that are true. We have about a tenth of a second delay between the time light hits the retina and the time of resultant perception, which is considerable given that you move 10 centimeters [four inches] in that amount of time even if you're only walking one meter [3.3 feet] per second. That means that if you didn't compensate for this neural delay, anything you perceive to be within 10 centimeters of passing…. [It] would have just passed you by the time you perceive it. You'd always be seeing the world as it was a tenth of a second earlier and seeing what the world looks like 10 centimeters behind where you in fact are--if you hadn't run into whatever it is you're looking for.
So, in the new work, you detail various optical illusions. (See related slideshow here.) Do these illusions result from all the errors in our visual system that need to be compensated for?
In this work, it's ones dealing only with forward motion, which is, I think, one of the main kinds of motion that we're good at dealing with. Even when you're standing still or rotating, for example, that's going to be a different kind of optic flow. Potentially, we're able to correct for those, too. But, all of these illusions turn out to be explainable from forward motion correlates. We're doing compensation all over the place. We play video games where there are made-up rules of optical flow that our visual systems can figure out on the fly.
In the new work, you were able to sort optical illusions into categories based on four visual features that were being misperceived. What particular features are those?
There are four different domains of misperception: The first is illusions of size. The second is illusions of speed. The third is luminance, or contrast. The last is illusions of perceived distance. Now, there are different ways of affecting those kinds of misperceptions—the key features that are causing those illusions. For example, size differences within your visual field could cause misperceptions or illusions of speed.
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Add CommentI've gotta call snake oil on this one. The Changizi all appear as just what they are to me. Nothing bulges, nothing moves. I suspect he got a big grant to make them and just 'cuz he says that's what ppl are supposed to see, they do. So, perhaps, he won a grant on the power of suggestion, not illusion? Mark, go to night school and get better photoshop skills if you're going to continue with this, I found your illusions passe and your theories on color a bit protracted.
Reply | Report Abuse | Link to thisYou possibly not up to the end are of value the work performed by you. Nevertheless, your article as is impossible by the way. Also it is very well put in the concept developed by me. Possibly, subjects of my site (http://www.spast.ru), on which work is presented (http://www.spast.ru/book/Inform/Inform.htm), can seem to you a little attractive if you wish to familiarise with it. Nevertheless, it is very pleasant, that in the future works to me on whom will refer.... Instead of to convince only to the thoughts. Your experience is important, not only for me but also for a science as a whole.
Reply | Report Abuse | Link to thisBy the way, whether you studied this mechanism at primacies? I think, that degree of a prediction at them should be even above, than at the person - using and other more developed mechanisms.
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It's not snake oil. If done right, the brighter center should appear to expand outward in brightness. But this is also not an illusion. The nearer an object is, the brighter it is, and vice versa. Light waves, like gravity, are proportional to the square of the distance from one point to another. As you approach a point source of light, the number of photons reaching your eye from that given point increases as well. The only illusion, if it could be called that, comes from the fact that there is a gradation. In that respect it works like Christmas chase lights, because our eye will follow a single shade or color as if it were a fixed object. In this case, it's neighboring shades that are changing, which makes one ring appear to "move" outward as our eyes rapidly (and PHYSICALLY) approach.
Reply | Report Abuse | Link to thisIncidentally, a simple zooming animation (wherein all the shades remain constant, but we make them larger), will not produce the same effect, because there must be a physical separation. A camera panning (not zooming, but actually moving) quickly to or away from this piece (on computer or paper) will produce the same effect.
Incidentally, image 6 of 10 has the same root explanation as the sphere with the center that appears to brighten outward upon a fast head bob forward, or physical approach of the eyes.
Reply | Report Abuse | Link to thisThe reason the lighter part of the rectangle appears tilted toward us is because this really is how light from physical objects works. As you approach a point source of light, the number of photons reaching your eye from that given point increases as well. Thus, we know on some level, (regardless of whether it is conscious or unconscious, the physics remains the same) that an object of uniform shade and hue will be "dimmer at a distance", and relatively brighter up close.
This is similar to the "illusion" of 3D borders in windows. On your screen, look at any button or 3D frame, or your slider bar to the right of this page (assuming yours is 3D). The left and top edges will be light, and the right and bottom will be dark. That makes it come "out" at you. If you reverse this, the object will appear to be sunken in. The left or right components are really arbitrary, and can be shifted. It's the top and bottom edges that produce the illusion. Why? Since 99.99% of our direct lighting comes from above, our brains have come to expect this, and interpret objects accordingly.
Your theory, Mark, makes me blush! It is from a typically male perspective, because it leaves out the main evolutionary root of our colour vision: FOOD foraging! Which, for our nimble-fingered primate forefathers, must have been fruits & berries and the like, up in those ancestral trees! Females may well have been the main fruit pickers, and their much higher colour sensitivity bears witness to this survival factor. (Colour blindness is twenty times more common in males, who, in Neandertal times, found their own survival niche through hunting, when there was not much fruit picking possible, due to the Ice Ages.)
Reply | Report Abuse | Link to thisI am constantly amused when I watch men at parties eating nothing but brownish-black meat slabs, thereby avoiding essential phytonuntrients from plant pigments. Eating a salad is considered 'unmanly'! Only when prostate cancer often strikes in middle age, tomato red lykopene seems to get back into the picture...
For a science-based , yet light-hearted approach to our daily diet, view Colour Eating on youthevity.com
"demonstrated that the shapes of letters in 100 writing systems reflect common ones seen in nature: Take the letter "A"it looks like a mountain, he says. And "Y" might remind one of a tree with branches. He also showed that across different languages most characters take three strokes to write out. That's because, he says, three is the highest quantity a person's brain can perceive without resorting to counting."
Reply | Report Abuse | Link to thisFirstly, writing systems arose using the rebus principle whereby pictures of natural things were selected to represent sounds that were similar to their names in language. It was not so much the selection of natural forms per se but the phonographic rebus principle that drove the use of pictures, and the fact that only natural forms can be depicted by pictures. All current writing systems evolved by graphical simplification of the pictures.
If you look closely you will see that the letters of the Roman and modern alphabets now bear almost no resemblance to pictures. Their linear forms arise from the execution of writing, simplicity for economy and most of the remaining attributes of shape arise logically from the simplest kinds of distinguishable graphical features.
Graphical features that arise for perceptual facility include symmetry and orientation to the horizontal and vertical axes.
I have this all worked out logically and you do not need to do any experiments.