reliability of eye-witness accounts

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If this were always true, how would I be able to process new, previously unknown, objects?

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Because they move. Or, if the object is stationary, you are moving. As a result they are detected by the motion-detecting black-and-white cones, and you will almost always glance there to see what it is.

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...and you will almost always glance there to see what it is.

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Almost always? The color question seems to come down to something like, "Is it possible to perceive some/any color/s outside of the fully-focused range?" Yes, the natural inclination is to move one's eyes. So tell me, for those who cannot move their eyes are they completely unable to sense color, or was Ben correct and there are a "few cones here and there" or baring that does the area of cones extend farther out than the fully-focused range?edited to fix quote tags.This message has been edited by Trae, 03-22-2005 11:35 AM

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Almost always? The color question seems to come down to something like, "Is it possible to perceive some/any color/s outside of the fully-focused range?" Yes, the natural inclination is to move one's eyes. So tell me, for those who cannot move their eyes are they completely unable to sense color, or was Ben correct and there are a "few cones here and there" or baring that does the area of cones extend farther out than the fully-focused range?

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Well yes as I understand it there are some cones outside the fovea, rather than a strict delineation of one from another. But whether the brain is actually equipped to take colour data from those cones may be a different question. B/W sensors only have to measure intensity, while colour receptors have to find colour and intensity; so if the "wiring" under the rods cannot accept colour data, it would not be transmitted, only the intensity data.But I do not know if that is actually how it works. It might be that you have some limited colour senses in the peripheral vision.I don't think that inabiolity to move your eyes would prevent you sensing colour. You would still sense colour, but would probably not be able to update the internal representation of your surroundings by moving your eyes to check what is there. I would expect you would be effectively blind to anything stationary in that zone*.

Understood..I wasn’t suggesting that people unable to move their eyes saw color differently. Though I understand your point about update the internal representation . I singled them out since with their heads immobilized they would not be shifting their view.I still suspect that my original limits of the focal area is smaller and within the area you’re considering.edited to add.Trigger Happy TV was just on. While most the participants are simply ignoring the action, occasionally you do see the effect of failure to recognize something right infront of one's face.This message has been edited by Trae, 03-24-2005 03:46 PM

Another thought that recently occurred to me is how focussed we are when reading text. I mean text is tiny - a fraction of an inch tall. And yet we can focus on the letters such that they become a virtual reality, to the exclusion of all else if we get really into it. Perhaps you also have the experience of failing to notice that the light has changed, due to being engrossed in reading.

That was along one of my observations earlier. That when I really focus on a single word my ability to see nearby words, without moving my eyes, is very limited. Much more so than I would have thought. I'd say it is roughly a word to either side.

Here is a lecture by Christof Koch at CalTech. He's one of the leading researchers in consciousness, specifically visual consciousness. This lecture was given as a part of an introductory class in cognitive neuroscience.Lecture 9: Attention and ConsciousnessThe whole thing is very relevant here; especially the first 40 minutes. If you're really pressed for time then I would recommend starting around "20:00" and ending around "40:00"--that's where the bulk of the experiments are available for you to try (You can try the experiments simply by watching the lecture). However, if you watch just the beginning, you'll miss explanation of other important experiments, and what inferences are drawn from the currently available experimental data.There are many examples of what kind of information our attentional systems gather, and what they can ignore. I would encourage anybody interested in eyewitness testimony, attention, or memory to watch the lecture. From the experimental evidence you'll get a better picture of how we work.edited to add subtitle.This message has been edited by Ben, Thursday, 2005/04/07 11:14 AM