As we have done already - after reading chapter 5 in Visual Intelligence, go through your text and find out how the text discusses the material in the reader and any additional detail it might offer. You will need to turn in a mind map in class on Tuesday so it might be a good idea to make a mind map before you start the next part of this project.
Try to adhere to the format below - keep the numbering for organization.
1) Discuss what you read in the reader. Think about what you learned from the reader. What were the main points the author was trying to make? What were some examples he used? What was the most interesting part of the chapter - etc.? Don't simply answer these questions; these are just some things to ask yourself before you start writing. I am pretty open to what you write about.
2) Discuss what you read in your text. How did the author of your text book go about addressing the related material? What did you find out about the topic that wasn't covered in the reader? What did you find interesting that was presented in the text? How difficult was it to find the related material in the text? Again don't specifically answer these questions, just use them as a way to think about the material. Feel free to experiment with your own style.
3) After you have had a chance to think about the material - what parts do you think you will remember and what parts do you think might fade from memory sooner.
4) Make a list of the terms and terminology you used in this post.
1) Chapter 5 discusses the way which we perceive color. The author discusses what factors will change the way we perceive the same colors in different situations. The author begins by discussing how the brain is connected to the eyes. The brain can in fact perceive colors without the eyeballs. When the lingual and fusiform gyri are stimulated in the brain they produce images of colored rings and halos. If either of these is damaged, color perception will be damaged. The opposite visual field of the damaged brain area is affected. Damage to this area of the brain will result in viewing the world in gray hues. The reader also discusses in depth about how our color perception makes watching movies entertaining. A movie is flashes of color being projected on a screen, and our brain puts all these colors together to form the characters, and setting of the movie. Our brain perceives these as objects, and movement so that we can follow the story of a movie, and enjoy ourselves.
2) My textbook discusses that the two most important features of color vision are creating perceptual segregation and signaling. My book also discusses how physiological research is done to better understand colors. My textbook discusses metamers which were also discussed in the reader. Metamers are two lights with different wavelengths distributions appear to be the same color if they stimulate receptors in the same ratios. This means if 2wavelengths produce the same neural response, they will appear similar. This is further stressing the point the reader makes that eyeballs aren’t responsible for color, but it is the way in which our brain interprets this data.
3) Some points I think I will take away from this reading was the metamers. After reading about this information in both sources I feel I have a good grasp on the concept. I also think I will remember to think about going to a movie theatre a little differently. I had never thought about a movie this way, so it was a new and interesting concept for me. I thought about how our perceptions of television would be less exciting as well if didn’t perceive the colors as objects, and instead saw splashes of color. I think the information that will fade from my memory will be the terminology from this chapter. There were many scientific terms to describe the color wavelengths, and how our brain breaks color down that I was interested in and did not commit to memory.
4) Metamers, lingual, fusiform gyri, colored rings, halos, wavelengths
1)In chapter 5, it focused on color; how and why we perceive the colors that we do. It begins with a few stories on different eye problems involving color. Cerebral achromatopsia is when someone can’t see any color. Hemiachromatopsics is when the person can see color from one eye and not another; like in the picture where half the painting is in color and the other half is only gray. These disorders occur from a problem with the occipital lobe, specifically the lingual and fusimorm gyri. When these two parts of the brain are damaged, the person can only see grays. Specifically, with hemiachromatopsics, the damage is only in one cerebral hemisphere.
The structure of the eye and how it connects to the brain plays a part in color as well. The left visual field (not the left eye) sends the image to the right hemisphere, and vice versa for the right visual field.
The color shuffle was an example in the book that helped describe how color is seen. How we see color depends on light, local reflectance, and a wide area of visual fields. With regards to local reflectance, low frequency is seen as red, moderate frequency is seen as yellow, and high frequency is seen as the color blue. The color shuffle also had two different pictures; one had the colors change gradually and the other example had abrupt changes in color. Gradual transitions show illumination change while abrupt changes are seen as a change in the surface color.
2)The textbook has more information on the impact of light on how we see color. For example, it says that fluorescent lights change the perception of color.
The text also talks about the impact of local reflectance on how we see color. The text says that how we see color mainly is determined by local reflectance. However, it only depends on the percentage of light reflected and not amount of light reaching the eye. This leads to the idea of color constancy. This is determined by our previous history with colors, chromatic adaptation, and the surroundings around the color.
3)I will remember the eye disorders because those are always interesting to learn about. I will also remember that our eye visual field sends the image to the opposite side of the brain.
4)Cerebral achromatopsia, hemiachromatopsics, occipital lobe, lingual, fusimorm gyri, color shuffle, local reflectance, color constancy, chromatic adaptation.
1) Chapter 5 was solely focused on the perception of color. The chapter was started talking about Hemiachromatopsics and how a painter was in a car accident and lost his color vision. I thought that it was fascinating that there was such a thing(obviously not for the person who has it). Another cool thing that they did in this chapter was the perception of color and how we percieve the color being there when it is really not. For example the neon worm and the red and black line example. And that we percieve more color in the second picture than the first.
2) In my book there wasn't anything I could find on the topic of Hemiachromatopsics. Instead I read a little bit about Age and Physical Conditions dealing with color perception. As you may have guess, color perception decreases as a person ages and can possibly be quite of a dramatic increase for some. My books stated that this is due to the cystalline lens in the eye and how as we age this lens gets yellower and therefore our color perception gradually darkens. Another thing that I found fascinating is that blue is the fastest deteriorating color. We tend to loose sight of the blues in the world before any other. I wonder why that is. People don't often realize their deterioration of colors as they grow older because they don't compare what they're seeing with others, therefore they don't realize that the color that they are seeing is actually a darker hue than that of someone younger or another person.
3)The information that stoood out to me the most throughout my readings are the ones that I read in my Sensation and Perception book about how your color vision starts to decrease with age. Also that blues are the first colors to deteriorate over time.
4)Hemiachromatopsics, Crystalline lens, color perception
1. Chapter 5 of visual intelligence was full of information. The chapter started off telling the story of two individuals with achromatopsia and hemiachromotopsia. Achromatopsia is color blindness resulting form an accident that injures the cerebral cortex. Hemiachromotopsia is color blindness in one hemisphere of the brain resulting in half of your visual field being color blind. The chapter then goes on to discuss how the brain interprets color through gradual and abrupt changes in color. What I found most interesting in this chapter was the definitions of hues, saturation and brightness of colors. I had a good idea what hues and brightness were but the book gave a better definition and showed a chart of how brightness works.
The reader defines a hue as a how much red, yellow, green or blue are in a color. Saturation is the purity of the hue varying from natural to gray to highly pure hues like pink. Brightness ranges from barely visible to dazzling. The reader then explains that the human eye sees in three dimensions of color and a photometer measures color in many more. One of the examples used in this chapter was a square consisting of forty-nine different colored squares. In one square all the colors are adjacent to very similar colors. It’s like when you pick a color of text on your computer you see the colors set up next to similar colors or colors of a different saturation. The next square showed all of the colors scrambled. When you picked out one color from the first square and tried to find its match in the second it was a little harder to do. This was showing that when you see a color you construct the color. The color you see depends on what’s around it. Just like in the past chapter talking about constructing images, we construct colors based on the wider visual field. The other example in this chapter I liked was a chart that showed how saturation, hues, and brightness all affect each other. (Page 129)
2. In chapter four of my text the author explains what chromatic colors or hues are as well as discussing saturation. The text then goes into color wave lengths which were also discussed in the reader. The text also defined an achromatic color as black gray or white a little differently than the reader. The text also poses the question of, how many colors the human eye can determine? It came up with 200 discriminable colors, 500 values of brightness, and 20 values of saturation. Multiply those together to come up with 2,000,000 different colors recognizable to the human eye. I think that is a crazy number. I also think its a little funny that when my fiancé and I were discussing colors he thinks every color out there is a color that came in the normal size crayon box. If he is shown something blue no matter what shade it is its still blue to him. Now I can prove to him there are 2,000,000 different colors out there not just the 24 box of crayons.
3. I think I will definitely remember what I learned about color construction. What you see isn’t always what you get. It depends on what is around what you are seeing. I can’t imagine being color blind or having half of my visual field be color blind. I had never heard of hemiachromotopsia before reading this chapter.
4. Hemiachromotopsia, achromatopsia, hue, saturation, brightness, cerebral cortex, photometer, chromatic colors, achromatic colors, wave length, and color construction.
1) The reader discussed a lot of examples and rules about illumination and light. It contained helpful pictures to demonstrate what it was saying. I found it interesting about the diseases of missing the L, M, and S pigments. It is linked to the X chromosome, so men are more likley to get protanopis (L), deuteranopia (M) or tritanopia (S).
2) My text talked a lot about hue and achromatic colors. There was this awesome picture that was in the text showing how much pigment of S M L it contained and what color it produced. I put it in my mind map. It shows cone responding to what color perception. The link is the same example in my text, but it is not color coded here
http://www-psych.stanford.edu/~lera/psych115s/notes/lecture5/images/color20.jpg
3) I will remember the pictures in the reader about illumination and light. Those helped a lot. I enjoyed reading about the L M and S pigments and their names if you are lacking one of them. I liked the 49 colored squares that were randomly shuffled and how we see them as a single color, where as the other 49 sqaure colors flowed together.
4) color, pigment, protanopia, deuteranopia, tritanopia, hue, achromatic color, illumination, light, cone responding
1)The reader talked about hue (the amount of reds yellows greens and blues in a color) and saturation(the purity of the hue). It also talked about the eye seeing in three dimensions of color and a photometer that measures many more. I liked that there were a lot of pictures to describe what they were talking about it helped it to be less confusing.
2)The text also addressed hue and saturation in chapter 4. I thought the definitions and pictures in the reader were less confusing than those in the text. I did howerver learn that the human eye can see 2,000,000 different colors. I don't feel like I have seen that many colors before ever!
3)I will remeber hues and saturation and hues the most and also that we see 2,000,000 different colors!
40 saturation, huse, photometer, dimensions
1)Chapter 5 discusses color percepterion. It begins by discussing why some people have a lack of color censation, called cerebral achromataopsia, which occurs when there is damage done to the cerebral cortex, causing a loss of color sensation throughout the entire cisiual field. It also discusses the term color shuffle. To describe color shuffle they gave us two different photos with 49 different squares of the exact same colors but in a different sequence. It was difficult to match up the exact same colors in the two different pictures and colors that looked like they were the exact same were actually different shades from each other. This chapter also covers how we perceive images in 3 color dimensio9ns of hue, saturation, and brightness and how this all begins at the retina using cones and rods as the two types pf photoreceptors. Rods in our eyes mediate our vision in low light and cones mediate our vision in bright light. There are three different kinds of cones (S, M, & L) which each respond to different levels of frequencies. In each of these there are two types of genes, Opsin, and Retinal and if one of these genes is absent, color blindness occurs.
2) My textbook disucusses the basic principles of color perception such as wavelengths. The text materials was very similar with the reader in disucssing cones and rods and the three different types in our eyes. I thought it was interesting how the text talks about how we can't see colors under the moonlight or dim lightvery accurately because dim light stimulates only the rods in our eyes and this photoreceptor does not permit color vision. One thing that was in the text that was not stated in the reader was that although it may seem strange, color is actually not a physical property although many may think it to be.
3) Somthing that stood out to me in the reader and alos the text that I found interesting was Sir Issac Newton's theory on prisms and their ability to create colors. This stood out to me because when I was little, I used to collect prisms and hang them from strings from my window ceil and when the sunlight would hit them they would create a rainbow of different colors on my wall and ceiling. I used to just stare at this and was always amazed at how pretty it was. The reading material states that this is becuase light reflects in different rates called frequencies. The yellow colors are reflected from interemediate frenquencies, the blue colors from high requencies, and the red colors from low frequencies.
4) Cones, rods, Cerebral Achromatopsia, Opsin, Retinal, Hue, Saturation color shuffle
1.) This chapter focused on color perception. It began with a couple disorders that people may have when having trouble perceiving color, like cerebral achromatopsia, where the person sees no color, just shades of grey, and hemiachromatopsia, which is a lesser version of the first disorder, where the person sees half in color, half in grey. The reader then went on to describe how a person has these disorders is because of damage to certain areas of the brain like the lingual and fusiform gyri. There was focus on what our perception of color is dependent on not only light but the rest of the visual field and how we interpret changes in hues as a change in brightness or surface, depending on how smooth of a transition is made from hue to hue. It showed pictures of a bunch of colors and in one picture they smoothly went from one color to the next and the other they were shuffled up to illustrate this as well as the fact that sometimes the same color can look different in two different context because of it's surroundings. A lot of emphasis was put on light, and how it can effect what we see. We tend to see something and assume that only one light source is hitting it, and we usually assume that this light source is overhead because naturally thats where ours is (the sun). Towards the end of the chapter the Young-Helmholtz Trichromatic Theory of Color Vision was discussed and how that theory centers around us seeing in 3 colors, red, yellow, and blue. The cones in our eyes see colors in bright light conditions and they do this by the frequency of the light that is reflected. Proteins called opsin and Vitamin A called retinals are in each cone, and if a cone is lacking one, then the person experiences colorblindness depending on what pigment they are lacking it on.
2.) My textbook had a lot of good information about colorblindness and the different types, and how the majority of people aren't really color blind, which I'm sure most of us know, but there are about 10 out of every 1 million people who see only in greys black and whites because they have no functioning cones. These individuals wear dark sunglasses because if they didn't they would see everything in normally lighted situations with a really bad glare because their rods aren't meant to work when there's a lot of light. It also talked about cerebral achromatosia and how that disorder is caused by damage to brain, rather then being hereditary, like the first case of colorblindness mentioned.
3.) I thought that the disorders were the topic that stood out to me most when reading this chapter. I usually find these to be the most interesting parts of the book and I really like how the reader incorporates a couple different disorders associated with what is talked about in the rest of the chapter. I also enjoyed some of the pictures that were included in this chapter, like the neon worm and the color shuffle.
4.) Cerebral Achromatopsia, Hemiachromatopsia, lingual and fusiform gyri, hue, Young-Helmholtz Trichromatic Theory of Color Vision, colorblindness, pigments, cones
1) Chapter 5 of the reader focuses on color. The chapter begins by giving us an image of seeing half in color and half in shades of gray. This is followed by actual accounts of such vision. To see only shades of gray is called achromatopsia. This is caused by damage to the lingual and fusiform in the occipital lobe. Studies of the brain in this area have led to the discovery that there is a section of the brain strictly devoted to the construction of color.
The chapter continues on to show us that we create color as we do lines. This was done using one example from Wallach. In looking at a sequence of short blue lines, we create a blue worm. Throughout the chapter, our perception of color is compared to a photometer which is a device that studies light. Color is said to be constructed at the same time we are constructing objects, shapes, and illumination.
Chapter 5 then goes on to discuss grays. Our perception of grays is due to illumination. The way we see grays is due to the principle of generic views and generic positions which says we choose the most stable combination of shape, color, and source.
Aperture display is also discussed. It can differ in hue, saturation, and brightness. We were also informed that we have three types of cones that respond differently to light. The types of cones all have different pigment molecules with instructions from genes. When genes are defective, color blindness is a result.
2)My text talks briefly about luminance. It says that luminance creates spatial differentiation.
My text also, mentions that there are different types of cones that we use to see different colors and briefly talks color blindness. My text doesn't say anything about color that the reader doesn't cover.
3)I think, as in most chapters of the reader, I will remember the example of the person with the visual problem. In this case it was the may with achromatopsia. I will also remember that the left hemisphere constructs our right visual field and not the vision in our left eye. I will also remember that we have different types of cones we see color with.
The things I won't remember are the things about how we see grays because I thought it was boring.
Terms: achromatopsia, lingual, fusiform, occipital lobe, photometer, illumination, Aperture display, cones, spatial differentiation
Chapter 5 of the reader focused mainly on color. The chapter started off talking about a man named Jonathon who was an artist, and then we was involved in a minor car accident that damaged his cerebral cortex, and he could no longer see colors or even imagine them. Verrey saw this case, and hypothesized that the optical lobe, the posterior part of the lingual and fusiform gyri was the portion of the brain devoted entirely to the construction of color. The reader focused mainly on the way our brains construct color. An example of constructing color they used was the “neon worm “, there were black lines on the outside and blue lines on the inside, and our brains construct so that we see blue and black even when there is nothing there, it is almost as if we see a neon light. They also gave an example of construct of color in the color shuffle, where you see different colors depending on what is next to that color. Rule 24 was very interesting; it stated that we put light sources overhead. An example, the book gave of this was a muffin pan, it looked as if there were 5 muffins in the pan and one dent, but if we turned the book upside down it would be completely opposite. Another example of this is Corrugated Mondrian, which I found to be the most interesting part of the chapter. Using the Corrugated Mondrian you can see that reducing the angles between planes, will reduce the strength of the vertical groupings and hence reduce the differences in lightness. Meaning if you make corrugated Mondrian flat the colors will more easily resemble each other.
2) The text discussed a lot about shapes and forms. They gave an example of the Sine wave which has different levels of light waves depending on the darkness and lightness of the waves. It also discussed data driver processing which detects shapes. The text went over laws of grouping, and how our brain groups things together. The law of proximity groups things that are near each other together. The law of similarity groups similar things together. The law of good continuation groups things that have a gap in them as continuing. The law of closure closes gaps in a “unit”. The law of common fate groups things that appear to be moving in the same direction together. This chapter also focused on shape consistence and the Gestalt approach, emphasizing things as wholes.
3) I definitely will remember the reader a lot more than I will remember the material from the text. The reader gave really interesting examples, and made the point they were trying to get across clear. I will remember most of the drawings from the reader, like the neon worm, but I will most likely remember the Corrugated Mondrian longer than any of the other material.
4) Cerebral cortex, constructing color, vertical groupings, gestalt approach, neon worm, corrugated Mondrian, data driver processing, Law of common fate, proximity, similarity, good continuation, closure, and Laws of grouping.
Chapter 5 of the reader focused mainly on color. The chapter started off talking about a man named Jonathon who was an artist, and then we was involved in a minor car accident that damaged his cerebral cortex, and he could no longer see colors or even imagine them. Verrey saw this case, and hypothesized that the optical lobe, the posterior part of the lingual and fusiform gyri was the portion of the brain devoted entirely to the construction of color. The reader focused mainly on the way our brains construct color. An example of constructing color they used was the “neon worm “, there were black lines on the outside and blue lines on the inside, and our brains construct so that we see blue and black even when there is nothing there, it is almost as if we see a neon light. They also gave an example of construct of color in the color shuffle, where you see different colors depending on what is next to that color. Rule 24 was very interesting; it stated that we put light sources overhead. An example, the book gave of this was a muffin pan, it looked as if there were 5 muffins in the pan and one dent, but if we turned the book upside down it would be completely opposite. Another example of this is Corrugated Mondrian, which I found to be the most interesting part of the chapter. Using the Corrugated Mondrian you can see that reducing the angles between planes, will reduce the strength of the vertical groupings and hence reduce the differences in lightness. Meaning if you make corrugated Mondrian flat the colors will more easily resemble each other.
2) The text discussed a lot about shapes and forms. They gave an example of the Sine wave which has different levels of light waves depending on the darkness and lightness of the waves. It also discussed data driver processing which detects shapes. The text went over laws of grouping, and how our brain groups things together. The law of proximity groups things that are near each other together. The law of similarity groups similar things together. The law of good continuation groups things that have a gap in them as continuing. The law of closure closes gaps in a “unit”. The law of common fate groups things that appear to be moving in the same direction together. This chapter also focused on shape consistence and the Gestalt approach, emphasizing things as wholes.
3) I definitely will remember the reader a lot more than I will remember the material from the text. The reader gave really interesting examples, and made the point they were trying to get across clear. I will remember most of the drawings from the reader, like the neon worm, but I will most likely remember the Corrugated Mondrian longer than any of the other material.
4) Cerebral cortex, constructing color, vertical groupings, gestalt approach, neon worm, corrugated Mondrian, data driver processing, Law of common fate, proximity, similarity, good continuation, closure, and Laws of grouping.
1) The main thing that I got out of the reader was the different ways we construct different shades of certain colors. For the most part I think that we understand the differences between black, gray, and white. And our eyes are able to figure out the differences between the three colors. However when these colors are intertwined it starts getting a little more difficult because of the surrounding backgrounds. If you have a gray dot inside of a dark background it will seem darker than a gray dot in the middle of a white background. Even though both of the dots are actually the same shade of gray. Its just interesting to see the different ways that we construct shades of a certain colors, and the way that we bring all of the colors into perspective. It was interesting in the beginning of the chapter how they talked about cerebral achromatospsia, how its a loss of color vision because of damage done to the cerebral cortex. It goes on to talk about the different cones we have that help us respond to different types of light. For instance how a shirt inside of a mall would look great compared to if you finally got it outside under the sun light it may look different.
2) In my text it talks a lot about the same things that the reader does. It says how perceptions are constructed by the mind. Which I think relates to the different parts of gray and how we interpret different shades of gray to actually be darker based off of its surroundings when they are actually the same color of gray. My text also talks a lot about the likelihood principle saying that we will perceive the object that is most likely to be the cause of our sensory stimulation. Also talks about hypothesis testing saying we will put the color we think is most logical to its surroundings. This deals directly with the reader and how a gray dot will look darker when inside of a black background because of its surroundings.
3) The thing that sticks out the most out of both the book and the reader is how we perceive different shades of gray to be darker or lighter compared to its surroundings. I would have never thought that we construct different colors like this but now it makes sense. Also with how different perceptions are constructed by the mind is important because it is actually our brain that is telling us that certain shades of gray are actually lighter or darker.
1) Chapter 5 of the reader is focused primarily on the ways in which we perceive color. To illustrate and expalin the complexity of color perception, the cahpter continues with more discussions of the anatomy of our eyes and our brains, color vision disorders that disturb color perception, and the chapter also explains additional rules of perception using illusions to illustrate the concepts in an understandable way.
THe reader's explanation of the anatomical structures which aid in color perception include the ways in which cones respond to color according to the lighting condition, as well as the specific structures in the brain called the lingual and the fusifrom gyri in the occipital lobe. Stimulation to these brain areas causes one to see rings or colors, and damage to these brain areas alters color perception.
One type of disorder related to damage to the regions in the occipital lobe responsible for color perception is called Cerebral Achromatopsia. In this disoreder, no color is seen, and the suffere is only able to visualize the visual world in grayscale. The other disorder discusse is termed Hemiachromatopsics which allows the individual to perceive color in one eye but not the other depending on which side of the brain was damaged.
THere are a number of complex rules our brain automaticall follows in order to determine the finite differences in color. A number of these deal with light sources, and the surrounding colors that assisit our brains in deciding how to interpret color. Two excellant examples of the latter include the color shuffle, and the Michael White figure (Hoffman, 1998).
2) The textbook discusses the evolutionary importance of seeing color in that color allows us to do things such as find edible berries in a bush. The text also discusses a few of the leading theories of color vision. These theories include Trichromatic Theory - which focuses on 3 receptor mechanism to expalin color vision, and Opponenet Process Theory - which expalins color perception as responses to opposing responses to color.
Like the reader, the text also discusses the importance of light in color perception, and how our brains compenssate for different lighting conditions to determine the color of objects. Such as the ability to accurately see a black lab in low indoor light, as well as bright light outdoors.
Color defiency is discussed, but primarily as it relates to genetic color blindenss, and not in the way the reader does, with specific brain damaged areas completely wiping away a person's ability to perceive color (Goldstein, 2007).
3) From the reader, I will recall the importance of the cones and the brain areas to help a person see color as it relates to the disorders (whose names are far too long to remember). And one of the things I will remember from the text comes from a concept presented by Isaac Newton. THis concept states that we don't actually see color, but our brain has associated certain colors with differeing wavelengths, and communicates color to us as a way to indicate the wavelength size - thus differentiating objects in our visual field - an important survival mechanism.
4) Terms: lingual & fusifrom gyri, Cerebral Achromatopsia, Hemiachromatopsics, Trichromatic Theory, Opponenet Process Theory, wavelenghts
1. Ch.5 in the reader goes on to explain how we perceive color. Firstly, we see a common myth about the brain and its connections. It does not connect on opposite hemispheres, as in left to right, right to left. In the diagram, we see that we connect to both sides of the hemisphere equally. The color shuffle was quite interesting, in that we can see two different colors depending on where we place them. This showed that color is not just dependent on the type of light we see, but also the different angles we see them at. This tries briefly to mend all of our concepts together at once. We create shapes, which we organize into objects. Once we organize these different objects, we place light sources onto them that illuminate them for us. Once illuminated, we decipher the color of the light and sequentially, the object. The reader also talks about frequencies and how they relate to waves. Waves can be rapid or long, these are much like light waves. Different frequencies are deciphered by the eye as different colors.
2. The text talks about chromatics, as the scientific study of color. It goes on to explain about electromagnetic radiation, and how the colors we see are in this visible light spectrum. I've had some grasp with this, as I've taken astronomy before and radiation is an important part in that study. Like in astronomy, Isaac Newton was a big part in the study of color. He coined the idea of a rainbow with his study of prisms, and inspired later scientists like, Goethe, to produce the Theory of Colors. The text also talks about the different types of rods and cones we have that aid in perceiving colors. It also touches on the ventral stream, which has alot to do with the V1 area of the cortex that we have read alot about.
3. I think for this portion of the reader I will remember more things from the text than the reader itself. With my previous background in Astronomy it was easier to relate to the linear parts of the book like color and radiation, than the images in the reader. The reader was helpful in elaborating on the text in this case, when it is usually the other way around.
4. illumination, frequencies, color wavelengths, electromagnetic radiation, ventral stream, cortex
chapter 5 the main ideas of this chapter is the way the brain function in allowing us to see color starting in the rods and cones, as light is reflect through the retina, the signals that allow us to see the image is the optic nerve which sends a message to the left and right brain as it travels to the visual cortex locate in the occipital lobe. Based on a study by neurologist Oliver sacks found that a patient had cerebral achromatopsia. Which is a loss of color vision affects the inferior part of the occipital lobe, in the lingual and fusiform gyri. If you get damage to one portion of the hemisphere it can affect the function of seeing color in the left hemisphere, or if you get damage to the right hemisphere you can no longer construct color in the left vision field that leads to the seeing color and gray called hemiachromatopsia. The colors or the hue, saturation, and the brightness changes the illumination gradual depends on light sources’ and the surface(s) of a figure such as grain, wood, ink on paper. The gradual change and the translation changes the image which can be use as light reflects on or around the image or figure from overhead direction such as graying or darkening such as in the photometer’s that displays a verity of hues in the saturation is also called the purity of it (hue). The photoreceptors recognized by the rods vision low lights and the cones bright light.
In the text it is covered in chapter 7 Goldstein (2007) it states that color helps in facilitate perceptual organization. The four basic colors, that help in giving us our visual spectrum is blue and green located in the middle of the spectrum and yellow and red that are in the long wave length end of the spectrum. The saturation make colors brighter or darker, by changing a wave length in the spectrum can create about a million different colors. If a situation which has two physical different stimuli can be perceptually identical is called metamerism, and if they have two identical fields in a color matching experiment they are called metamers. There are three type of wavelengths monochromat one wave length, dichromat needs two types of wave lengths, and anomalous trichromat needs three wavelengths. With that in mind there are two forms of color blindness which are monochromatism which is due to not having any function of the cones. The other is dichromatism that has three forms called protanopia: instead of seeing the gray color wavelength 492 nm. The deuteranopia the perception of color of yellow across the spectrum the neutral point is at 498nm, and the tritanopia sees blue as short, and red in long wavelengths. If there is damage to the brain it is called cerebral achromatopsia, color blindness. As we perceive a color of objects it can change do to illumination, and how the light reflects off of an object.
The parts that I believe that will stick in my head is how illumination functions and how it is processed in the brain, the perception and the wave lengths which can show different ways in which each person sees different things, as the colors are perceived as it travels through the retina, to the cones/rods and then through the optic nerve that crosses to the left and right hemisphere. If we cannot see color it is due to the damage in either part of the brain that affects the right or the left hemisphere of the brain which continues to travel through the optic nerve, the cones/rods. The hues of the color perception and the four basic color and the problems that effect blindness might fade because it sound different and is something that no one really pays attention to.
terms: Metamersim, matamers, protanopia, hues, color perception, illumination, wavelengths, spectrum
chapter 5 the main ideas of this chapter is the way the brain function in allowing us to see color starting in the rods and cones, as light is reflect through the retina, the signals that allow us to see the image is the optic nerve which sends a message to the left and right brain as it travels to the visual cortex locate in the occipital lobe. Based on a study by neurologist Oliver sacks found that a patient had cerebral achromatopsia. Which is a loss of color vision affects the inferior part of the occipital lobe, in the lingual and fusiform gyri. If you get damage to one portion of the hemisphere it can affect the function of seeing color in the left hemisphere, or if you get damage to the right hemisphere you can no longer construct color in the left vision field that leads to the seeing color and gray called hemiachromatopsia. The colors or the hue, saturation, and the brightness changes the illumination gradual depends on light sources’ and the surface(s) of a figure such as grain, wood, ink on paper. The gradual change and the translation changes the image which can be use as light reflects on or around the image or figure from overhead direction such as graying or darkening such as in the photometer’s that displays a verity of hues in the saturation is also called the purity of it (hue). The photoreceptors recognized by the rods vision low lights and the cones bright light.
In the text it is covered in chapter 7 Goldstein (2007) it states that color helps in facilitate perceptual organization. The four basic colors, that help in giving us our visual spectrum is blue and green located in the middle of the spectrum and yellow and red that are in the long wave length end of the spectrum. The saturation make colors brighter or darker, by changing a wave length in the spectrum can create about a million different colors. If a situation which has two physical different stimuli can be perceptually identical is called metamerism, and if they have two identical fields in a color matching experiment they are called metamers. There are three type of wavelengths monochromat one wave length, dichromat needs two types of wave lengths, and anomalous trichromat needs three wavelengths. With that in mind there are two forms of color blindness which are monochromatism which is due to not having any function of the cones. The other is dichromatism that has three forms called protanopia: instead of seeing the gray color wavelength 492 nm. The deuteranopia the perception of color of yellow across the spectrum the neutral point is at 498nm, and the tritanopia sees blue as short, and red in long wavelengths. If there is damage to the brain it is called cerebral achromatopsia, color blindness. As we perceive a color of objects it can change do to illumination, and how the light reflects off of an object.
The parts that I believe that will stick in my head is how illumination functions and how it is processed in the brain, the perception and the wave lengths which can show different ways in which each person sees different things, as the colors are perceived as it travels through the retina, to the cones/rods and then through the optic nerve that crosses to the left and right hemisphere. If we cannot see color it is due to the damage in either part of the brain that affects the right or the left hemisphere of the brain which continues to travel through the optic nerve, the cones/rods. The hues of the color perception and the four basic color and the problems that effect blindness might fade because it sound different and is something that no one really pays attention to.
key terms: Metamersim, matamers, protanopia, hues, color perception, illumination, wavelengths, spectrum
1) Chapter 5 of the reader is called The Day Color Drained Away. It focuses mainly on Cerebral Achromatopsia, neon spreading, and color theories and rules.Cerebral Achromatopsia is a disorder where an individual loses their color sensation because of damage to the cerebral cortex. People with this disorder see more in shades of gray than actual different colors. I found this to be an interesting disorder. To one day wake up and see the world in a completely different way because of the lack og color would be really hard to deal with. I think of all the different ways that color helps me in my everyday life, such as knowing if fruit is ripe or meat is cooked, using stoplights, and matching clothes, and it would be a big difference not having the capability of seeing them anymore. The chapter also talked about neon spreading. It gave the example of the neon worm and how it apears "glowing." Out of all of the differnt rules discussed in the chapter, I found rules 23 and 24 to be interesting. Rule 23 states that you construct as few light sources as possible and rule 24 states that we put light sources overhead. It gave the example of the muffin pan and how the shading and light makes your eyes think that the circles are concave and would be able to hold something.
2) My textbook discussed cerebral achromatopsia in some detail. It states that people with this disorder usually suffer from a stroke or injury before this occurs. It also talked about how these individuals see only in gray, like the reader discussed, but it made me think that these people are probably living somewhat depressing lives. To me, my life would be like a black and white movie if I had this disorder. It would be really sad and depressing for me going from seeing beautiful colors every day to living in a colorless world. The text also discussed differnt color theories, such as trichromatic theory of color vision, that explains that it takes three differnt receptor mechanisms to make color vision work. It also depends on wavelengths and light sources.
3) I think that I will remember the neon illusions and the information on cerebral achromatopsia the most. The rules probably won't stick in my memory for long because there was a lot of information on them.
4) cerebral achromatopsia, color vision, neon spreading
1.) Chapter 5 is called the day color drained away. This chapter focuses on color and the reader opens up with a story about a man named Jonatan I, who suffered a concussion in a car accident and two days later he realized he couldn't see color. Jonathan I was diagnosed with cerebral achromatopsia, which is a loss of color sensation through the entire visual field caused by damage to the cerebral cortex. The most typical cause of this is damage to the most inferrrior part of the occipital lobe, in the lingual and fusiform gyri. Researchers have found that if they stimulate the fusiform gyri in humans with magnetic fields, they reported seeing chromatophenes, which are colored rings and halos. The reader states that we don't need light or even our eyes to see color, just stimulation to the lingual and fusiform gyri. The reader shows a lot of different color drawings and as we learned before, the photometer will not be able to pick up the same images as our eyes do. The part of the reader that I found very interesting was what Ewald Hering came up with. He noticed that certain hues never coexist in our perceptions of colors. For example, we never see a hue that appears to be both reddish and greenish or both bluish and yellowish. These pairs that do not coexist are called opponent colors. Hues that coexist are reds and yellows in hues of orange, and blues and greens in hues of cyan.
2.) The text starts out by telling a similar story about a man named Mr. I, who suffered a concussion is a car accident could no longer see color. This was the same story that the reader explained. The text states that color serves inportant signaling functions, both natural and contrived by humans. Color also helps to facilitate perceptual organization, where the world is organized into seperate areas. The ability to tell one object from another and to be able to see objects against a varied background, is greatly facilitated by the ability to see in color. This is crucial to the survival of many species and it relates to the topic of camouflage that we discussed!
3.) I know that I will remember cerebral achromatopsia because it was mentioned both in the reader and the text. The neon illusions were also very interesting and I think that will stick in my head for a while.
Terms: cerebral achromatopsia, cerebral cortex, occipital lobe, lingual and fusiform gyri, hue, photometer
1) Chapter 5 was titled the day color Drained Away and deals with how we see color. The chapter stared off by talking about Mr. I and how he was diagnosed with cerebral achromatopsia. This disorder is caused by damage to the cerebral cortex and causes a loss of color throughout the visual field. The chapter then discussed color research and the frequencies of color. The frequence determines the color you see; Blue results from high, yellow from medium and red from low. We interpret gradual changes of hue, saturation and brightness in an image as changes in illumination and surfaces. I thought the best image in the chapter was the muffin pan. The pan helps us understand that we construct as few light sources as possible and that we put light sources overhead. The rest of the chapter talks about filters and how they don’t invert lightness and how they decrease lightness differences.
2) The first topic that I found in the text was the saturation of color. The text went into more detail on how the intensity of light changes how we see color. The text also mentioned achromatic color and its colors associated (black, gray and white). I also found out that humans can see 200 different colors, 500 varieties of brightness and 20 different saturation. The last thing that I found was that the text said that we have three different kinds of cones and rods.
3) The one thing that I will remember more than the rest is probably Sir Issac Newton’s first research on color. Using prisms Newton figured out that different frequencies caused different colors to appear. When light goes through the prism it is broken up and we are able to see all of the colors after they go through the prism. The other reason that I will remember this is because I have a Pink Floyd poster in my room and it shows light going through a prism.
4) cones, rods, prism, saturation, frequency,
1) The main theme of Chapter 5 is how we percieve and interpret the color that enters our visual system. The reader goes into detail about how our hemispheres decipher and construct color. The reader starts out by discussing a case of a man with cerebral achromatopsia, which is a loss of color sensation throughout the entire visual field caused by damage to the cerebral cortex. We perceive our color through the hemispheres in our brain its not just through our visual system. When the lingual and fusiform gyri are stimulated in the brain they produce images of colored rings and halos. If either of these is damaged, color perception will be damaged. The reader focused mainly on the way our brains construct color. An example of constructing color they used was the “neon worm “, there were black lines on the outside and blue lines on the inside, and our brains construct so that we see blue and black even when there is nothing there, it is almost as if we see a neon light. The reader also talks about frequencies and how they relate to waves. Waves can be rapid or long, these are much like light waves. Different frequencies are deciphered by the eye as different colors. Personally, I thought the most interesting part of the chapter was learning about how we perceptually visualize different color schemes and that its mostly in the brain hemispheres rather than our eyes that perceive the color.
2) In my text, I read about achromatic and chromatic colors. Whites, blacks, and shades of gray are achromatic colors. Blues, reds, greens, and yellows, are examples of chromatic colors. In addition to illustrating the difference between achromatic and chromatic color, the perceptual shift that occurs with the change from rod vision to cone vision raises a number of questions about the relationship between perception and neural processing,
3) I will probably remember the most how we eprcieve color and that its mostly in the brain rather than through the eyes. Its more about how we process what we are seeing than how we are actually seeing the colors.
4) Cerebral Achromatopsia, lingual gyri, fusiform gyri, frequencies, achromatic colors, and chromatic colors.
1) Chapter five continued to describe how we go about constructing our visual world with an explanation of how we construct colors. To hit this point home Hoffman begins with several examples demonstrating how we often create color where there isn’t any because it ‘makes more sense’ for there to be color there. Hoffman has been slowly progressing his main argument that every nanometer of our visual field is constructed by way of incredibly sophisticated rules; this chapter expounds this point by explaining how certain commonalities in our environment have caused us, by way of evolution, to interpret color in rather predictable ways. The rules which govern our experiences of color seem to depend largely on how we normally encounter color; viz. light comes predominantly from above us, and changes in positioning in the environment effect the color as well.
We are not like a photometer, which Hoffman routinely makes reference too. We don’t just measure color point by point since first, this would take way to long, and second, rarely do we see a color with an unobstructed view and perfectly clear light. We know that often light sources, real or artificial, cast shadows, and changes in angle effect how this light hits the object. One example of this is his picture on p.120 where flattening out the image causes us to be able to see that the two squares are the same color, whereas the angled view created two different shades.
Hoffman makes a reference on p114 that I think beautifully explains how we construct color, and it’s also a perfect metaphor for being a good magician. This quote is in regards to the two images which depict a gradual color change of the 49 squares, next to the random assortment of the squares. In one we construct a smooth surface with four light sources in the four corners, in the other, we see nothing but random boxes and no light source.
“It’s not that sometimes you try to create visual worlds and sometimes you don’t. You try to create them every tmie you open your eyes. It’s just that you can’t do something with nothing; put garbage in, and all that your visual intelligence can do is put garbage out. It takes a lot of work not to put garbage in…”
We generally attribute changes in color to changes in surface or illumination or both. Objects don’t change color for no reason. So whenever we can we try to make this fit, but the random assortment shows how this isn’t always possible. Hoffman makes reference specifically to a good film maker, but the analogy works for a magician as well. You have to work just hard enough to exploit the rules of visual intelligence, as long as the visual field is “close enough” to real life, the visual intelligence fills in the gaps according to what is would normally see under the same circumstances.
2) The first part of Ch 7 which discusses color was pretty boring to me and took a long time to read. It goes in depth into various aspects of color-blindness that were interesting but not like a lot of the other stuff in the reader or later in the chapter. I did enjoy reading about the difference between additive and subtractive color mixing. With paints it is subtractive mixing so that only the colors emitted by both of the mixing colors is reflected (in their example green is reflected from both blue and yellow). Whereas with lights, additive mixing, all of the colors that are reflected by each of the individual lights are seen. So blue, yellow, and green colors would be reflected back creating white light.
I really enjoyed the more elaborate description of color and light constancy discussed in the text. One explanation for color constancy, which is the fact that we can perceive the same color even with changes in illumination, was a phenomena known as chromatic adaptation. I remember this being discussed in cognitive psychology regarding faces, where if you stare at a picture of either Bush or Kerry for about 30 seconds the neurons which process that face will become fatigued such that if you then look at a picture with the two faces combined you are more likely to see that opposite person depicted. With color adaptation you become “fatigued” from viewing everything as skewed by the type of illumination (say the tungsten light) and so the change in perception of the color seems less than it really is. There is a similar effect with changes in light intensity since you remember the ratio between light and dark as opposed to the amount of light and dark. Ratio’s remain constant regardless of intensity.
3) The parts that I think I will remember are the points of disagreement between the two sources actually. Or maybe the points that they simply explained differently. For example the text discusses how we see shadows in explaining the visual intelligence of color. One experiment was to see a shadow cast by a cup on a table, when you color the boundary with a black marker it obscures the “shadowy edge” and you instead view the shadow as a change in color of the surface. Hoffman explains this in terms of rules we use to distinguish figure from ground, t-junctions, and the rule of generic images. Basically Hoffman uses more specific rules to explain how we see color.
When you draw the black line at the border you know that if it were a shadow you should see “mach lines” not a clear crisp edge, so if it is a shadow then it is only by some bizarre accident that the border is crisp. Similarly the black circle forms a part boundary according to the “minima rule for silhouettes,” rule 16, and we construct a new part as opposed to a shadow.
As the book progresses the overall relationship between his different rules is becoming more clear.
4) Photometer, illumination, color blindness, additive and subtractive color mixture, color and light constancy, chromatic adaptation, figure, ground, t-junctions