As part of my thinking and writing process for this mood ring project, I did some research. Here are links to sources that were helpful, and a few passages that I found particularly interesting. I will keep adding to this list as I work back through my notes.
To read more about my writing process, see my log entries with the tag, vision.
Georgina Kleege’s Sight Unseen
The biggest inspiration for this project is Georgina Kleege’s 1999 book Sight Unseen. Not only did she give me the idea for trying to find my own blind spot, but she inspired me to think more about vision and blindness and to bust the binary between seeing and not seeing.
At the end of her introduction to Sight Unseen she writes:
…my goal is not merely to expose my blindness to the reader’s scrutiny; some general insight can come from introspection. I also hope to turn the reader’ s gaze outward, to say not only “Here’s what I see” but also “Here’s what you see,” to show both what’s unique and what’s universal. I invite the reader to cast a blind eye on both vision and blindness, and to catch a glimpse of sight unseen (5).
In another essay, from the summer of 2020, she defines casting a blind eye:
To offer a different perspective on the subject, to provide observations devoid of the distractions and manipulations of images and to foreground other sensory perception as well as knowledge outside the sensory realm.Georgina Kleege, “Look Into My Eyes”
How we See, some Basics
Sight vs. Vision: sight is the functioning of the eye itself while vision is the functioning of the eye and brain together.
vision, another way of describing it: not just seeing with our eyes, but the ability to understand, almost instantaneously what we see, with our brains (The Visual Thing).
So if you take anything at all away from this talk tonight, please try to remember: Vision is information processing; it is not image transmission. Your visual system does not just transmit an image of the world up to your brain, because there’s nobody up there to look at an image. There’s nothing up there except nerve cells and all they do is either fire or not fire. So seeing is whether some neurons are firing and some neurons are not and what information those cells are extracting by the firing patterns from the pattern of light that lands on your retina.video lecture by Harvard neuroscientist Margaret Livingston about vision and art
Light enters through the cornea and travels to the retina in the back of the eye where it hits the photoreceptor cells–the rods and cones–which emit electrical impulses that then travel through the optic nerve to the lateral geniculate nucleus (LGN) in the thalamus and then to the primary visual cortex (v1). Here, the analysis (or interpretation? or processing?) of visual data starts and the image begins to be reconstituted. Data travels through V1 and V2 and continues its path: to determine the what of the object, it travels the ventral pathway to the temporal lobe; to determine the where, it travels the dorsal pathway to the parietal lobe.
Rods and Cones
There are two kinds of photoreceptor cells in the retina: rods and cones. Cones are densely packed in the center of your vision while rods are in the periphery. Cones are responsible for color and fine detail/visual acuity. They make it possible for you to read and to recognize faces.
In terms of recognizing color, there are 3 types of cones: blue or short, green or medium, and red or long:
Each of these photopigments has a different sensitivity to light of different wavelengths, and for this reason are referred to as “blue,” “green,” and “red,” or, more appropriately, short (S), medium (M), and long (L) wavelength cones, terms that more or less describe their spectral sensitivities.Cones and Color Vision
Before being diagnosed with cone dystrophy (well, first misdiagnosed with Best’s Disease in 2016, then Cone Dystrophy in 2018), I had never heard of cones and rods, or if I had, I didn’t remember hearing of them. The first two things my doctor said to me in 2016 was that I would need to look at someone’s shoulder to see their face (looking through peripheral vision) and that my retina was made up of rods and cones and my cones were scrambling.
Working on this mood ring project, I have learned more about cones.
things I’ve learned about cones:
- You have a lot less cones than rods (120 million rods to 6 million cones)
- Each cone cell connects? transmits? to only one neuron, while there are many rods for each neuron
- Cones are very important: for reading, seeing details, making sense of shapes, seeing things quickly
- The outer layer of the cone cell has discs which contain the protein photopsin (rod cells have rhodopsin). When these proteins absorb light a chemical reaction occurs and then electrical impulses travel through the ganglion cells to the brain
- cones are named cones because one part of them sort of looks like cones (although, having looked at various diagrams of them, I don’t really see it, but maybe that’s because of my lack of cones?)
As I continue to lose cone cells–how many do I have left?–my rod photoreceptor cells remain. Most likely, they will stay and I will learn to see sideways (the title of my chapbook: when i cannot see straight, i will see sideways). Rods help us see in low light and involve our peripheral vision.
peripheral vision: the side vision; the things you see that you aren’t looking at directly; the larger landscape/background
If central vision represents the trees, peripheral vision is the forest. I will never lose the forest, even as the trees fade further.
The peripheral visual field for humans extends 100° horizontally, 60° medially, 60° upward, and 75° downward.All About Peripheral Vision
[note: I think peripheral vision will be a new section for this larger project!]
central (cones) vs. peripheral (rods) vision
what vs. where
A balance of these two systems play an important role in reading. We use our central vision to identify the words we are actively reading then we use our peripheral vision to help guide our eyes to where they need to land next so that we can read the subsequent words in the sentence. If our central vision wasn’t working, we would not be able to see the actual word. However, if our peripheral vision wasn’t working, our eyes would possibly direct us to a few words down a few lines versus the next word in the sentence. Comprehension would be near impossible.Central vs. Peripheral Vision
Some interesting facts that I might have learned but always forget because some part of me is resistant to retaining scientific information:
- 30% of the neurons in the cortex are for vision; 8% for touch; 3% hearing
- there are 4 lobes in the cortex: frontal (cognitive functions and voluntary movement); parietal (temperature, taste, touch, pain, spatial positioning); temporal (hearing–and more); occipital (vision) SOURCE
Ever since ophthalmology became a science, its practitioners have been obsessively preoccupied with only one aspect of the total, complex process of seeing—the physiological. They have paid attention exclusively to eyes, not at all to the mind which makes use of the eyes to see with.Aldous Huxley’s The Art of Seeing
Human perception is patently imperfect, so even a normal brain must fabricate a fair amount of data to provide a complete sense of our surroundings. We humans are lucky that we have these fancy brains to chew up the fibrous chunks of reality and regurgitate it into a nice, mushy paste which our conscious minds can digest.Alan Bellows
The brain, explains neurobiologist Semir Zeki of the University of London, has to actively construct or invent our visual world. Confronted with an overwhelming barrage of visual information, it must sort out relevant features and make snap judgments about what they mean. It has to guess at the true nature of reality by interpreting a series of clues written in visual shorthand; these clues help distinguish near from far, objects from background, motion in the outside world from motion created by the turn of the head.The Visual Thing
Things the Machinery of our Vision Does
- see color
- detect motion
- identify shapes
- gauge distance and speed
- judge the size of faraway objects
- see in 3D
- fill in blind spots
- automatically correct distorted information
- erase extraneous info that clouds our view (blood vessels, noses)
Low Vision, Legally Blind, Blind
At my last vision appointment in 2018 (has it really been that long?), the doctor predicted that within 5 years my central vision would be gone. At least I think that’s what he said; the farther I get from that day, the easier it is to distort my memory of it. If this occurs, I will be considered legally blind, which is a legal, specific designation used for qualifying for state/federal benefits. It was coined in 1934 by the AMA:
- 20/200 vision (central) or
- 20 degrees or less of visual field (peripheral)
This term only deals with 2 ways of seeing and is framed through person as worker, or child as student = future worker. Kleege writes:
The modern, legal definition (of legally blind) is arbitrary, a convention based on notions of what visual skills are necessary for an adult to be gainfully employed or a child traditionally educated. The definition has more to do with the ability to read print to drive a car than with the ability to perceive color, light. motion, or form.Sight Unseen
note: Doing some quick research about Minnesota and legal blindness, I found the official government site for State Services for the Blind (SSB). At the top, the different categories for users: For Teens, For Job Seekers, For Seniors, For Employers, For Vendors. Where do people who are not teen, not seniors, and not job seekers fit in here? I understand the need for helping blind people seek employment and that, as a category, blindness is framed through work/employment, but that is not the only way people identify–as teen, job seeker/worker, or senior. And, looking at their mission, it is not the only way they want to help people. The mission of the site is not just to help people get jobs: “We’re here to help Minnesotans live, work, read and succeed.”
The popular understanding of blindness–total blindness, no light perception–only applies to about 10% of people considered to be blind. (note: Kleege’s first chapter is all about blindness, as a literal and figurative term. She discusses how it is controversial for many reasons including how people self-identify: some identify as blind, others as visually impaired or legally blind or with vision loss or low vision.
Currently, low vision seems to be a popular term (as opposed to visually impaired or suffering from vision loss). While legally blind is an official, specific designation, low vision is less clear. Here’s how the National Eye Institute defines low vision:
Low vision is a vision problem that makes it hard to do everyday activities. It can’t be fixed with glasses, contact lenses, or other standard treatments like medicine or surgery.
You may have low vision if you can’t see well enough to do things like:
Recognize people’s faces
Tell colors apart
See your television or computer screen clearly
I can’t do many of these things, to varying degrees. I can still read, but it’s harder and takes much longer. Technically I might still pass a vision test at the DMV, but I don’t trust myself to drive. It’s hard when you can’t always see moving objects approaching and you can rarely tell where the stoplights are. I sometimes recognize people’s faces, but often don’t. I can tell some colors apart, but often see colors wrong–greens are yellow, oranges pink, dark brown/black/navy blue are the same color. And, I can “see” the television screen but miss a lot of what is happening.
In Kleege’s first chapter on blindness, “Call it Blindess,” she discusses how frightening blindness, as a term and experience, is for most sighted people:
The belief that human experience, both physical and mental, is essentially visual, and that any other type of experience is necessarily second rate, leads to the conclusion that not to see is not to experience, not to live, not to be. At best, the sighted imagine blindness as a state between life and death, an existence encased in darkness, an invisible coffin (30).
Perhaps it used to be for me too. When my doctor began describing my vision problems in 2016, my first question was, will I go blind?, which meant, for me, total darkness. That was all that mattered, I guess. I don’t remember if he said I wouldn’t before he said what I do remember: “You will have to look at people’s shoulders to see their faces.” I know I understood his answer to mean no and I was relieved, even though it didn’t really. To look at people’s shoulders means you need to use your peripheral vision because your central vision doesn’t work, which is one definition of legal blindness. Now, learning more about vision and blindness, learning to use the vision I have differently, learning to listen and be attentive in different ways, and learning to decenter vision as the primary sense, I understand blindness differently–not as devastating or something to fear. Yes, it can be a struggle, but more so I see it as an opportunity to explore new ways to be.
Blind Spots, Filling-in
A central scotoma is a blind spot that occurs in the center of one’s vision. It can appear in several different ways. It may look like a black or gray spot for some and for others it may be a blurred smudge or a distorted view in one’s straight ahead vision. Scotomas may start out as a small nuisance and then get larger or there may be several blind spots or scotomas that block one’s field of vision. Scotomas that develop in the periphery of one’s vision are not as concerning or disabling as those that develop in the center.What is it (Scotoma) and How does it affect one’s vision?
What is filling-in? It is the phenomenon in which an empty region of visual space appears to be filled with the color, brightness or texture of its surround. The brain is capable of filling-in the blind spot, borders, surfaces and objects.Visual Filling-in
Depicting Central Vision Loss
I believe that there is a problem with how central vision loss is typically portrayed in the media. Medical texts, journals, advertisements and even the websites of eye health organisations, portray central vision loss, and diseases of the macula such as AMD, and Stargardt’s Disease, as a big black spot at the centre of the visual field with perfect eye sight all around. These types of portrayals are meant to show what such diseases look like from the patient’s perspective. The problem may stem from the fact that most of these descriptions and pictures are made by people who do not have central vision loss – the voice of the patient is generally absent in discourses of eye health. I have found that these misrepresentations of vision loss are very different from my lived experience and that central vision loss is actually very hard to describe, whether in words or pictures. This is because the symptoms of central vision loss are dynamic and ever changing, they are always influenced by environmental, physical and emotional states. Such complex symptoms cannot be condensed into a simple catch all ‘black spot’.The Problem with Depicting Central Vision Loss