Thanks to Judith for providing the quote above in a comment in the blog - it spurred me to talk a little about vision and what we perceive when we look at something...
How much can we trust what we see? To quote a neuroscientist Professor Semir Zeki of UCL, "there is no reality, only brain reality". Or, to put it in my words, we can only interpret what our eyes see in terms of our own experience and our brain's experience of given situations - the brain creates a memory bank of information that allows it to interpret the signals sent by the eyes and we see.
So what we see depends upon how accurate our brain has been in deciphering the information supplied to it. The brain can be fooled by giving it conflicting or confusing information - a good website to look at is run by Dr R Beau Lotto of the Institute of Ophthalmology - Dr Lotto is also a lecturer in neuroscience at UCL - http://www.lottolab.org/Illusions%20page.html. In the image below the cube on the left shows 4 blue squares and the one on the right shows 7 yellow ones. In reality all these squares are grey - they appear differently because of the colours juxtaposed - this is an optical illusion.
How much can we trust what we see? To quote a neuroscientist Professor Semir Zeki of UCL, "there is no reality, only brain reality". Or, to put it in my words, we can only interpret what our eyes see in terms of our own experience and our brain's experience of given situations - the brain creates a memory bank of information that allows it to interpret the signals sent by the eyes and we see.
So what we see depends upon how accurate our brain has been in deciphering the information supplied to it. The brain can be fooled by giving it conflicting or confusing information - a good website to look at is run by Dr R Beau Lotto of the Institute of Ophthalmology - Dr Lotto is also a lecturer in neuroscience at UCL - http://www.lottolab.org/Illusions%20page.html. In the image below the cube on the left shows 4 blue squares and the one on the right shows 7 yellow ones. In reality all these squares are grey - they appear differently because of the colours juxtaposed - this is an optical illusion.
So how much of what we see is real? To us it is all that is real. Something only exists as you see it. For another it exists as he sees it. How similar is the way you see something to the way I see something? Some of my pictures shown here, and the video clips that I am working on, are intended to challenge perception and make the viewer consider what it is that he is 'seeing'. I am showing you my reality where I have all the clues as to what it is but I am witholding some so that you must interpret it based not only on what I give you, but what you imagine it could be.
These pictures, for example, are both of a similar subject...
2 comments:
Lynda,
So how does colour blindness fit into this comparison - our mutual friend, RC, would get very frustrated when I would ask what colour he saw as we both looked at, for example, a red car - the answer was usually "brown" or some times "green".
Are all colour-blind people seeing the same colour as each other, but not the same as the rest of us see?
Does their colour perception vary depending on the strength of their individual affliction?
Also, is their colour perception affected by external factors e.g. a subject's parents may have been (partially) colour-blind too and set their offspring off into the world with some distorted colour values when trying to help their c-b child resolve their problem?
Phew! Does anyone EVER see/interpret the same colour as anyone else????
Fascinating, eh?
Keep at it!
Tim
I think you're right when you ask does anyone ever see the same colour as anyone else - I'm pretty sure the answer's 'no'!
Yes, colour blindness depends on the strength of the affliction.
Actually I see colour slightly differently in each eye - rather darker in one than the other! This is more to do with vision in general though than colour blindness.
At the lecture I went to by Prof Zeki he showed images of the brain depicting the areas that deal with different aspects of vision - the slightest thing can affect the working of these areas - damage can sometimes be reversed and sometimes not. So a person who loses colour vision can still perceive form and motion, although a grey world is an unattractive world he can still funtion.
Whereas a person who cannot perceive motion cannot live without help/supervision (interesting use of that word).
An example he quoted of damage to the area decoding motion is a patient who can see a stationery object, say, a red bus: as soon as the bus moves she loses it completely and it suddenly reappears when it comes to a stop. Imagine how difficult that would be to gauge what is coming towards you.
So put potential damage to the visual cortex together with the inadequacies of some inherited genes and it's a wonder we see so well as we do!
Thanks for the comments - it helps me to have to answer the questions too!
Lynda
Post a Comment