Wide-eyed Wonder: an artist's musings on three-dimensional vision

Some are color blind. I am stereo blind.

Archive for April 2011

New online brain map aides visual system research

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One of the factors for developing strabismus as an infant is whether other family members have the disorder. There often is a genetic connection in patient family history.

A new online atlas of the human brain is now available to researchers and anyone else with an internet connection. The visual cortex is being linked to the presence of specific genes here: http://www.brain-map.org/

An article in yesterday’s Wall St. Journal explains

A project of the Seattle-based Allen Institute for Brain Science, the online atlas offers researchers a powerful new tool to understand where and how genes are at work in the brain. That could help them find new clues to conditions rooted in the brain, such as Alzheimer’s disease, autism and mental-health disorders like depression.

In these two normal male brains, the connection between normal vision development and any genes that have been mapped can be more deeply explored. As more human brains are donated to the atlas for mapping, one day I would imagine a brain representing 4% of the population with strabismus will be donated, researched and mapped.

When I visited the site and searched for “visual cortex” a data list from two donors appeared. One link to an 8 year old boy showed a list of genes found in his right visual cortex with a link to the related gene symbols and name, ENC1 or ectodermal-neural cortex 1. This link goes to a page which has links to additional research on ENC1.

The second interesting link is from the brain-slice image, which takes you to a page with all the slices, and the visual cortex areas are labeled. One can zoom in on any of the images on the right and even see the cells.

The Allen Institute online brain map is breaking ground, with potential for further research into genetic connections for strabismus and stereo blindness.

Until now, researchers have been hard-pressed to link symptoms of the diseases they study to the biochemistry of genes that might be responsible for them. [1]

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Written by Lynda Rimke

April 16, 2011 at 10:26 am

In search of verification

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As blankets of clouds give way to bluer skies and the light grows stronger, I am checking my vision with my red-green glasses. I want to see some color mixing between the right and left eye to verify teaming.

the graphic designer's color wheel

Red and green light mix to create yellow, unlike red and green pigments that mix to create black, so I should be seeing yellow, or what Vision Therapists call “luster” in the areas that I believe are starting to develop 3D.

This is the color wheel that designers for the web and print media use. Four color printing presses and photographic papers use black, yellow, magenta and cyan inks or film layers to create all the colors we see. Magenta, yellow and cyan (a sky blue) are represented in the inverted triangle. Computer monitors and televisions mix red, green and blue to create all the colors of the rainbow, including white. Red blue and green are represented in the base down triangle.  Half way between red and green is yellow, a perfect mix of the two.

This morning, my white bathroom sink was bathed in soft sunlight. I photographed it through the red and green lenses of my analglyphic glasses and layered each photo at 50% over a white background in Adobe Photoshop. Then I started erasing where my right eye has vision loss. This is pretty much what I am seeing when I allow my right eye to dominate by suppressing the left eye when I fixate on the top of the bathroom fixture while wearing the red-green anaglyph glasses. My best educated guess it that I am experiencing normal correspondence with eyes aligned, but my brain is creating a map of right and left viewpoints because my brain is unable to suppress the left eye in the areas where my right eye is blind.

My unique analglypic view of things

The red area is highly unstable, as I can switch back to left-eye dominance and make it completely green. My goal is to make the red area yellow, a combination of both eyes pointing at the same place at the same time: the top of the bathroom fixture.

The elusive yellow “luster” didn’t happen, probably because I was trying too hard and thinking about it too much. My attempt using a finger to create physiological diplopia easily made two faucets when I converged on my finger about 5″ in front of my nose. What eluded me was the single faucet about 20″ away and two fingers at 5″ that would verify that I was diverging to point both eyes at the faucet.

The elusive divergence, of which I am slowly gaining ground on the Brock string, is what is needed to see 3D more than 5-12″ beyond my nose, which is my current maximum distance with confirmed eye teaming on the center bead of the string.

The cereal bowl that became 3D was 8-12″ under my nose. So I’m fairly certain my 3D experience was valid. On April 6th I had written:

This morning I had just vowed I wasn’t going to try anymore today, after nearly driving myself crazy with looking for anything and everything 3D since getting up an hour before.

I picked up my bowl and resumed eating my granola and BLAM!— the rim of the bowl looked different. I could tell I had both my eyes rooted to it’s outer edges. The rim looked larger somehow, and was slightly misshapen in the upper right part of it’s curve, probably due to the edge of my blind area. I just kept gazing at it in wonder, and something else appeared within a blink: I could see the space inside the bowl, hollowed out and tangible, with my spoon resting against the bottom.

UP. DOWN. BOTTOM. These are such abstract concepts to me … not things to be SEEN other than depicted on a flat surface. But I am seeing these and other words that describe WHERE in three dimensional space with an explosion of never before understood meaning.

3D dishwashing and weeding fall into a more gray area, as those distances were about 16-20″ … in all probability, what I was experiencing was normal correspondence with a map of both right and left viewpoints, similar to what is depicted in the photograph of the bathroom sink.

“Ship’s Log” of Uncertain Seas

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The real voyage of discovery is not in seeking new landscapes but in having new eyes -Marcel Proust [1]

Wednesday April 6 Is it really depth perception?
At breakfast, I see my cereal bowl rim with distortion from right eye, both eyes feel anchored on the rim, and then came a strong perception of SPACE … INSIDE the bowl with my spoon resting at THE BOTTOM of it. Later I distorted the rim of my coffee cup with the same “eye teaming.” It looks as if it had been marred on the potter’s wheel. The distortion disappeared when viewed with each eye separately.

That evening, the dishes were all done in what looked like 3D, with the soapy water appearing further away, DEEPER INSIDE the sink … I decide to talk about it while it is happening. “I’m stere-oscoping!” I announce to Patrick in a sing-song voice “… the bowl is so big and NEAR as I wash it … and now I’ve made it small and FAR as I rinse … ” Was I really? Hope springs eternal.

Thursday April 7 OD&VT appointment or “Let’s see what we can see”

A visual field test of right eye reveals no vision in upper right half, save one small area above the dividing line on the nasal side of my central vision.

Visual field test, right eye

April 7th visual field test, right eye

(My Vision Therapy is always with my Developmental Optometrist. I had emailed her about my BRAO last week.)

Condolences are given and my OD/VT attempts to center-occlude my glasses over my right eye, to encouraging use of the left eye to strengthen it. I’m sure the expression on my face and direct protest that I was center occluding the left eye, not right, made her reconsider … “I’m fighting for my half-blind eye,” I explained. I do use my left almost all the time anyway and have no difficulty suppressing the right.

I share how I had restored my ability to “unsuppress” my right eye, and what I saw with the red green glasses when looking at a white wall (Dr. Press had suggested doing this in a comment to my April 1 blog post.) “I see total green on the top half of my vision and total red-orange on the bottom half.

“Could it be ‘left-eye over right-eye’ viewing that my brain has programmed?” I ask. She didn’t have a quick answer. (I’ve illustrated it in the image of my visual field test, above.) My fellow strabbie blogger, “Squinty” Josh, might guess that it’s a mega case of anomalous correspondence!

No 3D tests were done to verify my 3D breakfast bowl story. She made a comment that I was at step 5 before, and jumping to 20-something … she simply wasn’t sure what to do. I’m not surprised, as I never have done sequential anything well. I need to gulp the whole pie in order to understand any part of it. [2]

She took a long look at me on the Brock string, which looked the same way it does at home: both strings come into the bead, however the left eye nose-to-bead image (depicted to right) is weaker. Only one string goes out of the bead, as my blind right eye cannot see above the bead. Four and 10 base down prisms strengthened the left eye image in front of the bead and made it as clear as the right.

How my New Brock String appears

How my New Brock String appears to me

We work on the most basic part of my tranaglyph, which I can see completely if I turn it upside down. Right side up, the green upper right dot completely disappears. I need green on the bottom of my right-red visual field when viewing with red-green glasses.

Homework assignments are given on the tranaglyph and I’m to continue Hart Charts with left eye and new letter circling exercises, as well as eye control and thumb pursuits for the right.

We agree to bi-nasally occlude both right and left eyes as before to continue to strengthen peripheral awareness. She clarifies I am NOT using both eyes when I do this as either suppressed eye still turns to my nose behind the veil. I was hoping I was gaining some sort of peripheral fusion. Apparently not.

We agree to schedule an appointment in 3 months if my right eye vision improves.

Friday-Saturday April 7 & 8
Distraction

I’m pretty discouraged and don’t attempt much of anything, other than distorting cups, plates and bowls under my nose. I’m also majorly distracted because we finally agree with Freddie Mac on a price for the 5-acre foreclosed homestead we had won a bid on … way back in early February!

Sunday April 9 Renewal
I socialize and spend the afternoon at the homestead in left eye mode. My right eye looks turned in at every glance in the mirror. After visiting with my mother-in-law at the nursing home, I manage to still find the will to do my favorite phys-dip exercise in the ladies’ room, using the door stop on the wall. I can still make physiological diplopia both ways, converging and diverging. My creature even tilts his head back at me, just as always!

My inner kid wants Wonderland again!

Phys-dippity-do!

That evening, I walk the old yard and notice the grass at my feet looks grassier … each blade seems more distinct somehow in the evening light. I refuse to pursue the possibility of 3D and get down to the task of pulling bitter cress from the flower bed. It’s a small plant with white flowers that must be pulled before it throws seed everywhere in a couple of weeks.

I enter my usual zen-weeding-woman state, and it seems that both eyes engage, and the flower tops look TALL. I keep breathing and weeding, but my hand is not connecting as easily to the base of each weed. I check for eye teaming by covering and uncovering. Both eyes are fixed on the same small white flower, first one flower, then another. The bittercress continues to fill vertical space in a new way, even when I blink.

Was it really 3D, or simply weeding for the first time with my left eye instead of my right?

Later on, at Hibachi Japan, I fail to catch one piece of shrimp … of course! Perhaps if the chef had tossed it from below

Monday April 11 Surprise!
I find a small piece of shrimp in my purse!

More 3D, and a better prognosis

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I have a very good report, and there is no way to keep it short!

Yesterday’s appointment with the retina specialist gave me hope for the first time. The damaged retina is still getting enough blood supply, and so it may have a chance to heal. This is a far better prognosis than last week, when the resident ophthalmologist who saw me in ER and also two days later simply shook her head “no” with a long sad face, saying a 5 second delay in the artery to the fovea, as revealed by the angiogram, was not enough blood supply to prevent permanent damage.

fluorescent angiogram of BRAO

My fluorescent angiogram showing the artery to central vision filling in 7-10 seconds later, but still providing vital blood supply

Nothing much has changed in the size and shape of the brown shade pulled over this eye, but I now know that it will take about 3 months for the swelling to go down completely. I was also told there should be some improvement by my next appointment in 6 weeks.

Glory! So many folks have been praying and thinking of me. This great news is a tremendous blessing and I am grateful and truly humbled again by the all of the good thoughts and prayers for healing. They have not always been answered with “Yes” and so it has been hard for me to even believe in “Maybe.” But now I believe. What doesn’t kill you makes you stronger.

This means I am still on the road to 3D vision! In fact, the built-in sun visor on my right eye may even help me toward that goal!

First, I am forced to use my weaker, left eye in order to see anything completely: to read, write and to drive. A part of vision therapy strategy is to even the eyes out in skill level, so that they can team. My left eye is making rapid gains!

Second, my brain is doing new stuff. I believe it’s in a state of greater plasticity, simply because I cannot use the main eye-gate to the brain I have been using all my remembered life.

My plasticity has grown through these alternative ways of seeing:

LEFT-EYE MODE WITH RIGHT EYE FULLY SUPPRESSED
This monocular method has the greatest acuity, and was all I had at the hospital. It was my alternating-esotropic brain’s first choice.

But when I got into wide-open sky space the evening I left the hospital, I felt tangibly blind. Whole sky was absent to my right. It was so unsettling I vowed to use both eyes somehow, ASAP!

RIGHT-EYE MODE WITH PATCHED LEFT EYE
I walked the hospital hall this way and managed to see enough feet and cart bottoms to not crash into anybody. With great effort, I managed to read the large letters on the bulletin boards by looking just above the letters.

I also patch when Patrick drives down the highway, just to give the left eye a breather and look for any improvements. So far, I still only see the lane to the left, with center and right lanes occluded. Whole trucks disappear along with all the sky. Did I say driving feels un-nerving?

RIGHT-EYE MODE WITH HALF SUPPRESSED LEFT EYE
Partial suppression is the new thing my brain has done on it’s own these last few days, thanks to my vow to use both eyes, and some consistent work.

I started by putting on the bi-nasal occluded glasses, which revealed the blind area again because partially occluding the left made the right eye image fire up in my brain.

The next day, I removed the right occlusion. Gradually, after a couple of days of wearing the glasses with center-left occlusion for a few hours to rest my dog-tired left eye, I could see the blind area without the glasses. Amazingly, the blind area began to fill with input from the left eye, leaving only a band of blurriness across my central vision, and not the total tan sun-visor image my right eye sees. At first, it was light fixtures in ceilings. Now it’s just about anything, however, there is a blurry band at the lower edge of my blindness that remains. It wrinkles my central vision like a layer of unstable cellophane.

When I tested myself with red green glasses on a white wall, the top half of my vision was green and the lower half was … red!

Sometimes, when I occlude the right eye, the left eye stays fixed, and sometimes it jumps. So, instead of true binocularity, this is more like patched-together left-over-right viewing.

However, my eyes ARE in alignment at times, because the patched in area vertically lines up with the area I can see under the cellophane band with the right eye.

I get around the house better in this new left-top, right-bottom mode. It has become the new default mode when I move about; my brain does it automatically.

STEREOPSIS IN MY LOWER VISUAL FIELD
At times least expected, I am starting to SEE things 3D. I’ve found I can’t look at a thing and make it 3D, but when I give up sometimes it just happens.

This morning I had just vowed I wasn’t going to try anymore today, after nearly driving myself crazy with looking for anything and everything 3D since getting up an hour before.

I picked up my bowl and resumed eating my granola and BLAM!— the rim of the bowl looked different. I could tell I had both my eyes rooted to it’s outer edges. The rim looked larger somehow, and was slightly misshapen in the upper right part of it’s curve, probably due to the edge of my blind area. I just kept gazing at it in wonder, and something else appeared within a blink: I could see the space inside the bowl, hollowed out and tangible, with my spoon resting against the bottom.

UP. DOWN. BOTTOM. These are such abstract concepts to me … not things to be SEEN other than depicted on a flat surface. But I am seeing these and other words that describe WHERE in three dimensional space with an explosion of never before understood meaning.

“I want you to think WHERE and not just WHAT” was one of the first things my vision therapist coached me to do, when she gave me my center-occluded glasses. As an esotrope, I clearly understood my need to let go of WHAT, but had no concept of WHERE.

Now it shimmers under my nose when I least expect it, and vanishes like a fairy. But when it happens, adjectives that describe WHERE become an epiphany.

My new brain plasticity

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My eyes are straight … sometimes. And sometimes, when I look at a thing and cover and uncover each eye, I can tell that they are not moving.

I want this to be my new default mode. Two straight eyes looking at the same point in space at the same time.

I have a window of opportunity to create a new default mode because, last Saturday, I lost vision in the upper half of my right eye. My body threw a small clot or plaque into the lower branch of my right central retinal artery.

My husband took me to the emergency room Saturday afternoon because we both wanted an ophthalmologist to look at my retina, as I had experienced strange spots and gradually increasing loss of vision throughout the day. We both thought I was having a possible retinal detachment, but in fact what the ophthalmologist found was a branch retinal artery occlusion.

I underwent a battery of tests to discover the source of the clot or plaque. All tests show nothing abnormal happening anywhere in my body. For those interested, I have given this detailed report to my vision therapy and strabismic friends in a new discussion on BRAO on sovoto.com

As I type this, I am using my left eye only. My brain and eyes are in what Frederick W. Brock calls a monocular posture. This is because the central vision in my right eye is half blurred, so reading and writing with that eye are not possible.

Maintaining monocular posture, means that only one eye fixates the object of special attention. The eye that looks at the object of regard is the eye that is used for the cortical interpretation of that object. The other eye is not used for that purpose. The other eye may,be looking in an entirely different direction. This ‘eye may have, at the moment, a perceptual purpose or it may not. The question now arises, is it used for any other purpose? If it has no other purpose, is kept in “cold storage” so to speak, we have monocular posture, for what the other eye is doing at the moment is of no interest to the organism. [1]

But I am not resigning myself to molecular posture without giving binocular posture a chance. Call it my bargaining phase: I am noticing my eyes are straight at times, with catchlights spot on in identical areas of my pupils. Furthermore, at times when I look at things with both eyes, the area above my blurred central vision is filled in correctly. This first happened when I looked out the sliding glass door. The central post was aligned. This morning I looked at our fireplace, and the fire was visible above the central blurred line. An unlit pillar candle in front of the fireplace was also in alignment.

Binocular posture is the ability to maintain such relative eye positions in anticipation of a certain visual task that both eyes directly fixate a single object of special regard: Binocular posture means, essentially, looking at a single fixation object with both eyes at the same time.[1]

I also am able to still alternate. This is happening mostly when I am trying to verify if I have binocular posture … when I am trying too hard. Or when I consciously switch to my left eye while doing close work, like reading or writing.

Maintaining separate lines of direct gaze for each eye, or strabismic posture. In the sense defined here, it does not include all strabismics but is limited to those who are ambiocular in their visual behavior.. The term “ambiocular” describes a condition where both eyes are used for separate and distinct purposes. That is, they attend to different functions at the sanE time. We find this posture in “anomalous projection” of alterating strabismic.[1]

My goal, for the next six months while I am waiting for ischeal tissue in my retina and vision in my right eye to resolve, is to increase opportunities for binocular posture and decrease activites that require monocular posture. This means limiting reading, writing, drawing and painting, which my right eye cannot do. It means increasing my awareness of what it feels and looks like when I am using both eyes correctly, with the feedback I am getting from my blurred central vision and the areas above it filling in correctly, in alignment. I am making these concessions to train my brain to NOT concede vision with my damaged right eye.

Concessions occur when there is a lack of demand for all existing abilities … Visual training if it is properly applied, makes a demand for all existing abilities. [1]