Vision Therapy Reader - A free vision therapy reading appliction

A few years ago, when I was learning computer programming, I practiced my skills by creating a text reader application. I wanted to make an electronic version of a bar reader. A bar reader is a vision therapy tool that forces you to use your eyes together when reading. You can see an example of a bar reader on this lovely vision therapy blog here.

I never got around to releasing my application because I was being a perfectionist and I never felt like it was quite done. It was never quite perfect. But now I've decided to release it, in case it can help someone. It certainly can't help anyone just sitting on my computer.

When I wrote this program, I didn't know anything about web programming. So it's not a web app; you can't play it in your browser. You have to download it. I'd like to eventually make it a web app, but until then...

 How to install and open Vision Therapy Reader

1. Install Python
• Vision Therapy Reader is written in Python (a computer programming language). To use it, you must have Python installed on your computer.
•  There are two version of Python: Python 2 and Python 3. Choose whichever version you like - it doesn't matter for my program.
• Python is available for many operating systems - Windows, Mac, etc... Theoretically, my program should work on Mac. But I've only been able to test it on Windows so far.
• Download Python
2. Download Vision Therapy Reader
3. Unzip the VisionTherapyReader-master.zip file
4. If you installed Python 2, open the python2 folder. If you installed Python 3, open the python3 folder.
5. Click on VisionTherapyReader.py

 
How to use Vision Therapy Reader
You need red/green or red/blue vision therapy glasses.

You need some text. You can paste your own text in, or load a text file (.txt). Both options are located in the FILE menu.

Pasting text

 

You also need to calibrate the application colors to your specific monitor and glasses. In the COLORS menu, click CALIBRATE COLORS.

Calibrating the colors

There are two palettes available - red/blue and purple/teal. BOTH work with red/green or red/blue glasses. Try both and see which works best for you.

 

Now that you're all set up, you can play around with the options.

 

 Bar reader

 

You can use the bar reader.

 

You can change the palette between red/blue and purple/teal.

 

You can change the width and spacing of the bars. You can make fat bars, thin bars, far bars, close bars, whatever your heart (or eyes) desire. You can also play with the font.

 

 Color reader

You can use the color reader, where instead of bars, uses colored text.

Like the bar reader, you can play with the palette and the font.

You can also change how to text is colored. The words can be different colors, or the individual letters can be different colors.

You can include an "anchor" color, which both eyes can see.

 

Conclusion

I hope someone out there finds this application helpful. Let me know if it helps you, or if you're using it in your VT office. I love to hear that stuff :)

Spelling Bee - A free vision therapy video game

Play Spelling Bee here

I've finished another vision therapy video game!

Play Spelling Bee here

A game about spelling! And bees! (not really)


Requirements

• Google Chrome web browser
• This game uses a fairly new feature, canvas blend modes, and in my experience, this works best in Chrome
• Canvas blend modes are supported in Firefox, but it seems SLOW on my laptop
• Canvas blend modes are supposed to work in Safari, but I've never tried it
• Canvas blend modes are NOT currently supported in Internet Explorer
• Red/green or red/blue vision therapy glasses

Gameplay

A spinning hexagon bounces around the screen. Inside the hexagon is a word.

• If the word is spelled correctly, press UP
• If the word is spelled incorrectly, press DOWN
• If you need some more visual feedback, press LEFT or RIGHT to move the cursor underneath the word

Features

• Color calibration
• Adjustable
• time limit
• size
• speed
• bounce pattern
• Convergence / divergence
• Three color palettes
• Graph of hits/misses

Color calibration
To calibrate the colors to your specific glasses and computer monitor, just follow the easy color calibration instructions. 

Fully adjustable
Adjust the size, speed, bounce pattern, and time limit to suit your needs. 

Convergence or divergence
This game can be used for convergence or divergence vision therapy exercises. Just adjust the settings in the menu. Note: the numbers in the convergence/divergence settings are NOT prism diopters. They are just arbitrary numbers, based on pixels measurements.

Three Color Palettes
You can play with Red Blue Black, Purple Teal Gray, or Red Green Orange graphics. ALL work with your standard anaglyph glasses. Try all the palettes, and see which work best for you.

Graph of hits / misses
As you play Spelling Bee, the game keeps track of your correct and incorrect answers (hits and misses). After the game is finished, you can see in what areas of the screen you are getting correct answers, and you can see in what areas of the screen that you are getting wrong answers. This can help you find your strong / weak areas of binocular tracking.

Options menu

Graph of correct answers

Vision Therapy Goals
My main goals for this game are:

• Binocular tracking
• Antisuppression

In conclusion
Try out my binocular tracking game Spelling Bee and let me know what you think. Good luck!

Play Spelling Bee here

Space Owl - A free vision therapy video game

Play Space Owl here

It's long been my dream to create a vision therapy video game.... And I've finally learned enough about computer programming to make it happen!

Here's the result...

Play Space Owl here

A game about an owl in space!

Requirements

• Modern, up-to-date web browser
• I've tested it on Chrome, Firefox, and Internet Explorer. It works on all three, although the menu looks a little uglier on IE.
• I haven't tested it with Safari (because I don't have a Mac handy), but it's supposed to work with Safari. If there are any bugs, please let me know.
• This game uses HTML5, which requires the latest versions of web browsers.
• Red/blue or red/green vision therapy glasses

Gameplay

• Collect gems
• Avoid enemies
• When enough gems have been collected, you gain a point
• When you gain a point, something cool happens!
• Try to gain as many points as possible before time runs out

 
Features

• Color calibration
• Adjustable game speed
• Adjustable time limit
• Binocular OR monocular
• Two color palettes

Color Calibration
To calibrate the colors to your specific glasses and computer monitor, just follow the easy color calibration instructions.

Fully Adjustable
Adjust the speed and time limit of the game to suit your needs.

Binocular or Monocular
This game can be used for binocular vision therapy exercises, requiring both eyes, or for monocular vision therapy activities, focusing on one eye. Just change the settings in the options menu.

Two Color Palettes
You can play with Red Blue graphics or Purple Teal graphics.

BOTH palettes work with your standard anaglyph glasses. Through your glasses, the Red Blue graphics have a white-on-black appearance, while the Purple Teal have a black-on-white appearance.

Try both options and see which you prefer. Depending on your monitor, you may have better cancellation with one palette vs the other.


Vision Therapy Goals
My main goals for this game are:

• Anti-suppression
• Forcing both eyes to work together

Some graphics in the game can only be seen with the right eye. Some graphics can only been seen with the left eye. Therefore, both eyes are forced to work together to complete the game. If both eyes are not used together, then the game is impossible.
 
Some secondary vision therapy goals that may be addressed by this game are:

• tracking the player around the screen
• estimating distances between player, enemies, gems
• soft, peripheral focus when paying attention to incoming gems and enemies
• saccades when glancing around screen to look how many points you have or to see the time remaining

Visual Anchors
Sometimes gems appear that can be seen by both eyes. This gives each eye an "anchor" to lock on to, and can make accurate fusion easier.

Feedback
The game provides feedback when the player does something good or makes a mistake. When the player collects a gem, a nice sound effect plays. When the player collides with an enemy, a bad sound effect plays AND the player and all enemies become temporarily visible to both eyes.

Above, you can see in the second frame that, when the player collides with an enemy, the players and the enemies turn white, becoming visible to both eyes. This gives the player feedback about where his/her eyes were really pointing.

Loading
"Loading" is a term for adding increased layers of difficulty to a vision therapy activity. This "shakes up" the visual system, and forces the brain to adapt and learn new skills. I have tried to "shake up" this game in the following ways:

• The direction that enemies and gems fall from changes periodically, creating a shifting and unstable environment. The player must constantly adapt. Enemies and gems may come from above, below, left, or right.
• After a collision between the player and the enemy, there is a chance for the player and the enemies to swap colors. Suddenly, the blue player may turn red, and the red enemies may turn blue. The graphics visible to the right eye are now only visible to the left eye, and vice versa. Therefore, the player cannot get too comfortable and must learn to adapt.

Above, you can see that after the player has collided with the enemies, the colors of the player and enemies have swapped.

In conclusion
You still need to do vision therapy exercises in real space, moving your eyes and body around together, focusing on different distances, converging, diverging, etc... But now you have the option to play a fun video game, too. Please leave any comments or suggestions below, I would love to hear what you think about the game and how you are using it. I'm still tweaking it, and maybe I'll add music. But please, check it out and use it :)

Play Space Owl here

My first 3D movie experience

Last night, I saw Gravity in Imax 3D.

I've tried seeing 3D movies before, with no results, but I thought I would try again in light of my recent experiences with small amounts of 3D vision.

Before the movie started, there was a little intro for Imax 3D. You know, showing the logo, making a deafening noise, things like that. At the end of the intro, the camera zoomed into the Imax logo. Suddenly I felt my eyes start to cross, and I got the sensation that something was going to hit me in the face. I immediately tore the 3D glasses off my face in a panic. I can't even remember what I actually saw; I just remember the feeling.

After that, I thought, 'Wow! This is going to be an exciting movie!' But then... it really wasn't. The actual movie seemed kind of flat. And sometimes, with the white-suited astronauts on the black background of space, there was a lot of ghosting. C'mon Imax, can't you figure out how to show 3D without ghosting?

About halfway through the movie, I remember that I still had the blurry stick-on eye patches in my front pocket. So I stuck those to my glasses, to make the movie a bit softer. That seemed to help.

Sometimes, when the camera would show the inside of a space shuttle, it seemed like I was looking through a window into a real room. It looked clearer and more real. It only happened when the camera showed a small crowded room, like a space shuttle... I don't know why. Maybe it had something to do with the presence of lines of perspective and other monocular depth cues, which might have helped me add some depth. Just a theory.

And at one point, there was a tool floating around the inside of the space shuttle. It started floating towards that camera and, like the Imax logo, I thought it was going to hit me in the face. I gripped the arm rests and forced myself to watch it come at my face and I actually saw it coming out at me. Hurray!

So that's what happened at the 3D movies - flat the majority of the time, but there was a scary Imax logo, realistic/weird looking views into a space shuttle, and the floating tool coming out to hit me in the face.

Also, it was a good movie!

Vision therapy works and it's contagious

I started working at my optometrist's office a couple of days a week, helping out with some IT / database stuff. I'm on the computer the majority of the time, and I know it doesn't sound that exciting, but it has been... awesome. Just being in proximity to the VT office has affected me so much.

First of all, in two weeks, I've already met... I think five... strabismic patients who are seeing / starting to see in stereo. One patient developed the ability to see random-dot stereograms after SIX WEEKS of vision therapy. From no depth to rand-dot in six weeks is unheard of. To make it even more amazing, this patient had an ophthalmologist tell her and her parents that she was incurable.

It's really heartening to see all these successes. Strabismus really IS curable through vision therapy. Stereo Sue isn't a fluke. I would get on my hands and knees and beg every parent out there to never, ever let an ophthalmologist operate on their child's eyes without trying vision therapy first.

Secondly, being in this vision therapy environment has started to change my own vision habits. Being around the optometrist, the vision therapist, the patients, the equipment, the employees... Hearing snippets of vision therapy in action... "is it double or single?", "keep your head straight!"... It's all starting to make me more conscious of my eyes and my posture. I kind of feel like a hypocrite, walking around the office while letting my eye wander out and standing at weird off-center angles while talking to people. I feel like, since all the patients are trying to keep their eyes straight and their posture correct, then I should too. I should set a good example, right? So I've been trying to keep my eyes and face centered on what I'm looking at, at least when I'm in the VT office...
 
And then yesterday, something happened... I was having a conversation with a guy at the office and trying to be conscious to point both of my eyes at him. Suddenly I started to feel sick to my stomach. The hand that he was gesturing with looked weird. Kind of... more in front of his body than usual. His nose was looking weird, too. Extra triangular. It all just looked weird in a subtle way and it felt like I was getting punched in the gut.

I think I was starting to see in 3D a little bit...

I kept this information to myself for the day. I didn't want to claim that something happened if I was really just imagining it...

But then, while driving down the highway the past couple days, I would practice bringing my eyes together... And sometimes things looked "weird" again. The autumn trees were... bushier... clumpier... But only sometimes. And I thought to myself, well maybe I'm just paying attention to trees more. Maybe I'm imagining it and trees have always looked like that...

Full of strabismic doubt....

But then I started to thinking - I've seen so many successes at work. What if I just decide to believe myself? What if I just believe that it is possible? What if I just believe what I see? I've seen so many successes lately - why can't I be one of them?

So during my lunch break, I shared what I was experiencing with the vision therapist. "You're starting to see it, aren't you?" she said. We went over to the big flat screen TV, put on the shutter glasses, and started up some VT software.

(Actually I was wearing something extra besides the LCD shutter glasses and my prescription glasses. I remembered that I saw some depth once while wearing blurry contacts, so I tried to do something similar but less messy. I used those translucent plastic blurry eye patches that stick directly to your glasses - I put them on both lenses of my own glasses. Voila - blurry, soft vision.)

As the program started up, I mentally told myself "Stop doubting everything you see. Believe your eyes. Believe that you saw some depth in the clumpy trees and that guy's triangle-beak nose. Keep everything soft and relaxed and trust your eyes."

We started with the picture of the big rings that most people in vision therapy are familiar with (quoits):

I stuck my arm up to the monitor, putting my hand right in the center of the ring... And, weirdly, it FELT like my arm was going through a hole in the TV screen. When touching the center of the TV, the ring seemed to be at the level of my forearm. It wasn't "floating" or "popping out" really... Yet... somehow the ring was at the middle of my arm and my arm was going deep into the TV. It even seemed like it was possible for me to put my hand in through the hole and go behind the ring.

Neat!

Then we switched to a 3D picture full of sea animals. And some fish were clearly closer than other fish! I could answer most of the questions correctly. And once, when I manipulated the pictures so that I was converging A LOT, one of the fish REALLY jumped out for a second. But just a second.

Then lunch was over and a patient came in and it was time for me to get back to working on the database. And all this eye stuff was kind of giving me a headache... The end.

I'm still mentally processing what happened today... I really did see in 3D... I'm coming to believe that doubt, mistrust, and negativity are a big hindrance to succeeding in vision therapy. Sometimes you just have to trust what your eyes are showing you. Stop discounting the positive.

Concerns of adult strabismics

I've been talking online with a lot of adults strabismics, and I've observed that there a few particular concerns and topics of discussion that come up quite often. They are:

• Are strabismics really able to gain stereovision through vision therapy? Or is it limited to very, very rare cases?
• Do alternating suppressors have an easier time gaining stereovision than constant, one-eye suppressors?
• Do strabismics undergoing vision therapy commonly develop permanent double vision?

In my limited experience observing other strabismics that come through the vision therapy office, I had my doubts about these questions. I've seen many strabby children start vision therapy, gain stereovision, graduate vision therapy, and leave. I've never noticed or heard of a difference between alternating suppressors and constant suppressors. And I've never seen anyone end up with permanent double vision. But again, my experience is very limited.

So yesterday I decided to ask my vision therapist for her thoughts. She's been doing vision therapy for 11 years (and also works 50+ hours per week), so I figure she has a lot of experience to draw upon.

Here are her responses to my questions. (Note: These responses are paraphrased and from my memory.)

• Are strabismics really able to gain stereovision through vision therapy? Or is it limited to very, very rare cases?

When I asked her this question, she pulled out her iPhone and showed me some before and after pictures of several young patients (and one adult). They were patients who came in with strabismus and eye turns, very clearly visible in the pictures. And in the "after" pictures, they had perfectly straight, lovely eyes. She told me that she could think of the names of 10 patients off the top of her head who had fixed their strabismus and gained stereovision.

She said that the majority of success stories were children with no history of eye surgery. She also said that she didn't measure the success of vision therapy only by stereovision. Even the people who don't gain full stereovision are helped greatly - they don't have double vision anymore, they can read and drive again, they can study again, they can get good grades again, they can see again.

• Do alternating suppressors have an easier time gaining stereovision than constant, one-eye suppressors?

She said that, from her perspective, she prefers to work with constant suppressors. Alternating suppressors are "professional switchers" - they focus on "getting the right answer" rather than using both eyes together to accomplish a vision therapy task. Basically, they cheat! She has to avoid certain vision therapy exercises with alternators, since they just switch their eyes back and forth until they figure out a way to cheat. She viewed alternating suppression as a hindrance to vision therapy. Alternating suppressors are always foiling her plans and thinking up smart ways to cheat on VT exercises.

She then remembered off the top of her head a recent constant suppressor / deep amblyope patient who had just gained stereovision.

•  Do strabismics undergoing vision therapy commonly develop permanent double vision?

She said that patients sometimes experience double vision during vision therapy when both of their eyes "turn on", but that's just part of the process and goes away later when both eyes are pointed in the same place. In 11 years of being a vision therapist, she has never seen anyone walk away from vision therapy with permanent double vision.

A long overdue update

I'm still alive!

But I haven't done much vision therapy over the past few years. I meant to. But life got complicated and I lost momentum. And I was living abroad for a while, too, so that made things hard. And blah blah excuses.

I'm starting to get my passion back, though. I've had some time off work, and I've spent the past 5 months learning computer programming, developing some vision therapy computer games, and trying them out with patients at my vision therapist's office. It's been really awesome. Eventually I'll release the game out into the world, and hopefully make some more as well. Stay tuned. :)


For those who are curious - this is the current status of my vision:

I still don't see in 3D.

I can straighten my eyes at will and point them at whatever I want. Which, for me, is awesome. I've met patients at my vision therapist's office who have much better prognoses than me - e.g., they've never had any surgeries, they have quite a bit of depth perception in certain situations, etc. BUT they don't have as much conscious control over their eye muscles as I do. So that makes me feel special. And I can straighten my eyes out for pictures / first dates, so that's useful.

I still have some suppression, which allows me to function in the 2D world.

I'd say that my biggest obstacle is that my brain just doesn't "get" it, yet. I can overlap the input from both eyes - but it just looks like two slightly different superimposed pictures, fighting for dominance. For other people, two overlapping, slightly different inputs produces depth magic. But for me, no magic. Will it ever happen? I don't know!

A great experience

My vision therapist set up something really cool for me. She has another adult strabismic in therapy and she set up a time for us to meet and do a 2 hour block of vision therapy together. This other patient, let's call her... Tara, has had 8 surgeries, has been both an esotrope and an exotrope (currently eso), is a pretty severe amblyope in one eye, and  has double vision 100 percent of the time. My vision therapist thought it would be good if we got together, because she said we both "speak the same language" and might be able to help each other.

Finally, this Friday, we got a chance to meet and play around with some red/green stuff! It was great. It turns out that Tara's double vision allows her to "cheat" on most red/green exercises, and so far it has been very difficult for her to get any fusion or overlapping of the two doubled images that she sees. The images just don't want to overlap and make a combined picture, and she doesn't know how to move her eyes to move the doubled images over top of each other.

I started to get so interested in what was going on with Tara's double vision that I spent almost the whole time asking her questions and trying different things with her. One of the toys at the VT office was this ancient looking device that looks like two flashlights connected to box, with one flashlight projecting a red circle and one flashlight projecting a green dot.

When my vision therapist pointed the flashlights at the wall and put the green dot inside the red circle, Tara could not see the green dot inside the red circle. She saw the green dot to the left and under the red circle. When we were doing other red/green activities, she also mentioned that she saw double images that were vertically displaced.

 
From what I've read and heard, I seem to remember that vertical misalignment is harder to treat than an exo or eso deviations. If one eye is wandering out horizontally, then it is possible to learn how to pull it in. But if one eye is wandering up, it can be difficult to learn how to pull it down. Or so I've heard. I've also heard that if the vertical deviation isn't too extreme, the brain can compensate and fuse the images, but if it's too far, then it can be really hard.

I thought that maybe if she used a vertical prism, she would have more luck with fusion. I'm not sure if it's frowned upon to use prisms to help with vertical deviations, or if you're just supposed to "deal with it" until you suddenly have the eye strength to do it yourself, but I wanted to try it. So I ran and grabbed the box of loose prisms and found that a 6 prism diopter base down over one eye (or base up over the other eye) allowed her to see the dot in the circle. One image, no vertical displacement. Cool!!!!

We also did some other stuff and I tried out some ideas for physical diplopia practice. And then the three of us started brainstorming and came up with a neat idea for an exercise we want to develop involving black, red, and green felt and Nerf guns (details to come later). It was really fun and inspiring experience all around! I'm more inspired to do my own homework now, and it even made me consider maybe going to optometry school some day. Vision therapy is just so fun!

I'm back!

After 7 months, I have returned. My personal life became kind of crazy for a while (a serious car accident, among other things) and I kind of forgot about vision therapy. At that time, seeing out of one eye was good enough for me. But everything is okay now! I'm back in vision therapy, and I have even more ideas and inventions floating around in my head than before.

If you tried to email me, I'm sorry that I didn't answer. I will slowly try to go through my old emails and see what I missed. Thanks :)

To prove that I am really back, here is a picture of me doing one of my first back-in-vision-therapy homework assignments: wear the red/green glasses and track the red/green ball as it floats around your face. Thankfully, I'm finding that I can still flat fuse red/green stuff like that. It seems that I haven't lost any of the talents that I gained from the first round of vision therapy, but I sure do feel a little rusty.

Just a little

I saw a little depth at my last vision therapy appointment. For the first time! Just a little! But still... it happened! Here's the story...

In Effective Strabismus Therapy, Dr. Israel Greenwald talks a lot about working with strabismus patients to achieve red/green luster while looking at a white wall. The patient wears red/green glasses, stands up close and stares at a big empty while wall, and tries to make the colors intermix and become inseparable. To help achieve this, he recommends that the patient wear high plus lenses (+15 to +20). These high plus lenses are basically superpowered magnifying glasses that make everything blurry. This removes all figure/ground distinctions and allows for easier fusion.

I asked my vision therapist if we could get some high plus lenses and she said 'Sure!' She called in an order to the lab, and I thought everything would be fine. It turns out, though, that it's very hard to find a place that even makes plus lenses that strong. The strongest that I have seen available for order on the internet are +12. (+12 is actually very strong though and would probably work, but that's not part of the story.)

So last Friday, I brought up the topic of plus lenses again and my vision therapist had an idea. There were lots of contacts in the office, so why not try high plus contacts? That way, there wouldn't even be a chance to "peek around" the glasses and ruin the blurring between figure and ground. They weren't any +20, but there were some +6 available. (or maybe they were +4, I can't remember).

So I said yes, even though I was kind of terrified. (You remember what happened last time someone got all up in my eyes.) And it turns out, contacts are really hard to get in! I did the usual - hold your eyelids down like they are trying to escape - type of thing, but then I would involuntarily try to shut my eye so hard that my eyelids would turn inside out and block the contact anyway. It was both funny and gross.

20 minutes later, when they were finally in, I got to experience the world as myope (near sighted person). I actually found it quite nice. My eyes couldn't focus on anything and thus didn't try - it felt rather relaxing. It also blurred out everything past my nose, leaving me encapsulated in a blurry womb. I've always been an anxious and shy person, wondering what people are thinking about me (are they looking at my crooked eye??), and for once, I couldn't see anybody's faces. I just had to assume that everyone was smiling at me. I wouldn't want to live with uncorrected blurry vision, of course, but it was nice to take a vacation in blurry land for a while.

So we tried some red/green luster with the white wall, and the extra plus seemed to help (more plus would have been better, though). While, the contacts were in, we also tried some other things. I had some vague memories of reading that dim light can help fusion and help break suppression, and something about contrast levels.... and something about ARC and peripheral fusion... and something about something else... So we decided to try out some polarized vectograms while I was wearing the plus contacts, just for fun, and.... something happened!

First, I was looking at this "figure 8" vectogram:

I was looking at this one the previous week, and while rocking side to side, I noticed that one of the little triangles was moving with me. It only did it for a second, and I couldn't really get it to happen again, but I knew that this vectogram was doing something funny to my brain. So, while wearing the blurry contacts, I decided to start with this one.

I put the polarized glasses on and started to rock side to side like last time. And suddenly little triangles started popping off the screen! They didn't stay popped out for very long, but it happened more than a few times, especially (for some reason) on the triangles on the left hand side of the picture.

It reminded me of those pop-up story books - the kind where you pull a tab and little paper figures extend off the page. It was as if someone was pulling a tab behind the vectogram and making the triangles pop out. At one point, I even saw a wave of depth undulate across the vectogram and then disappear. It was pretty neat.

Excited, I tried another vectogram - the one my vision therapist calls "creepy clown."

Again, something happened! Nothing really popped off of the screen, like those little triangles did in the figure 8 vectogram.. It was more like... the screen fell away and I was looking through a portal into another dimension... A dimension of scary living devil clowns!

The area with the most depth was that area between creepy clown's legs, where you can see his two legs, his hand, and the stool. It's was very depthy in there. And yes, I do appreciate how creepy it is to have one of my first experiences with depth involve looking between a clown's legs. Some optometrist out there sure has a sick sense of humor.

Also, every time the screen fell away and got depthy, I got the strange sensation that someone was punching me in the stomach. That was pretty neat, too.

So that's the story. It wasn't in "real life", and it was blurry and unstable. But it HAPPENED. Up until this point, I have been secretly fearing that maybe I was born without those special binocular neurons. Maybe I became strabismic because my brain was missing some pieces... Now I know that's not the case. I just need to keep practicing.

What is "fusion"?

I'm writing this entry to describe my experience with "fusion" in vision therapy. I'm putting "fusion" in quotes, because I'm still not quite sure if what I am experiencing is fusion, or even what the definition of fusion really is. I know that, basically, fusion means two eyes making one picture. But what I've seen and noticed seems much more complex, and involves brain processes that I can't even begin to understand. In any case, this is what I have noticed about fusion so far...

First, I have noticed that fusion is not just one process. There seem to be several "types" of fusion that I have come across, and even within these "types", lines get blurred and things get murky. These types may even exists on a continuum. However, I will try my best to explain what I have experienced. Here are the three types of fusion that I have come up with:

1. Cut and paste
 This is the easiest kind of fusion for me. The images from each eye are selectively cut and pasted together into one image through some brain photoshoppery. An example of this would be the anti-suppression playing cards that I love so much.

When viewed through red/green(blue) glasses, these are the images that the brain must combine:

How does the brain do this? In my subjective experience, it feels as if my visual system is using scissors and glue to make a sort of collage.

Of course, it doesn't look like that. But it feels as if that's the process that my brain is going through - choosing the important elements from each eye, and deciding which to use in the final "collage." If the brain did not go through such a process of defining importance and cherry picking input, then what would stop the brain from making an image such as this?

The brain would not make the above picture, and one would never see the cards all blank like that. I dare you to try! The brain looks for meaningful input, and assembles everything together accordingly. That is why, when making anti-suppression activities, I am always writing letters on everything. I have learned from the playing cards that the brain cannot ignore letters.

For me, this type of fusion becomes more difficult as finer and more precise "brain cuts" and "brain pastes" are required. For example, fuse - by convergence or divergence - the image below:

What you should see is something like this:

This is quite hard for me to do, and I believe I know the reason why. Look at all of the places where the lines are in conflict (in pink). This would require some very creative cutting and pasting.

In fact, this comes close to requiring the brain to create a completely new image (rather than a collage), which brings me to the next kind of fusion.

2. Transmutation
In this type of fusion, something new is created that neither eye can see alone. This is not a composite of two images, as is the case with cut and paste fusion. Two images are combined in such a way that they create a new, unique third image.This is certainly not a collage. It's a new painting!

An example would be the "luster" effect. By convergence or divergence, fuse the two images below:

What you should see is one grid in the middle, with the red square and the yellow square magically transmuted into a new color. This new color was not perceived by either eye, it was created in the brain. (I imagine it will be glowing like it's fresh out of a nuclear reactor.)

This type of fusion is exceedingly difficult for me, and I'm not sure that I have properly achieved it. When I try to do luster activities, I tend to get flashing, alternating between colors, rather than the creation of a new color. I also imagine that stereoscopic vision requires a great deal of transmutational fusion, and thus it is very important that I get better at it! I can't be satisfied with merely cutting and pasting; my brain needs to learn how to blend and create.

3. Stereopsis
What happens here? I'll let you know when I see it. I've heard that salads, tomatoes, horse skeletons, steering wheels, and coat sleeves all start jumping out to say hello. It sounds pretty awesome.

My left eye - a VT update

(I've lost track of the weeks. They're just flying by!)

The theme for my vision therapy lately has been "back to basics." My vision therapist and I were talking, and we decided that we skipped over some important stuff in the beginning. With new patients, she normally starts out with a lot of monocular patched activities, tracking, pursuits, body bilaterality, and so on. But in my case, I was very eager and kept being like, "Wow! Is that a cheiroscope? I read about that. Can I take that home?" And so we got a little ahead of ourselves.

As I've been progressing and starting to really get a feel for my eyes, I've been realizing the importance of those beginning foundational activities. I'm becoming very aware of how unequal my eyes are, and I can see how much of a hindrance that can be. Therefore, for the past few weeks, we've been going back to those basic beginning activities.

Specifically, I've been working on my left eye - the amblyopic and frequently turned eye. Here is what I have noticed about it:

1. It is terrible at pursuits, especially going from right to left. It prefers a quick succession of saccades, or what Dr. Len Press told us are "catch-up ballistic saccades." My eye thinks that it's tricking me with these saccades, and that I won't notice that they aren't real pursuits. You're wrong, eye!

2. It has trouble knowing where it's pointing. I sometimes think that I am using the center of my eye to track something, but really I have stopped moving my eye (because the object has moved to a place where it's hard to move my eye smoothly) and I'm just seeing it my peripheral vision. My eye feels like that is "good enough" and doesn't realize that it's not even tracking anymore.

3. It doesn't like to initiate movement or be the leader. It just wants to follow what my right eye is doing.

4. It has trouble maintaining a stable gaze. When I try to fixate on something for more than just a second, my eye jitters around the target. I've witnessed this using the MIT and seeing the Haidinger brush dance around the target that I was (trying to) fixate on.

5. It's even nystagmus-y on occasion. Sometimes when I wake up in the morning and my right eye is occluded by the pillow, I will look at the alarm clock with my left eye and the image of the clock will jerk back and forth over and over.

(and I'm sure I'll discover more as time goes on)

Amazingly, I had no awareness of any of this until very recently. How could I not notice all these years?

Now that I have noticed, I have been busy working away on my monocular skills with activities like:

tracking / pursuits with the monster
word searches with progressively smaller letters
marsden ball tracking
MIT mazes
tracking while keeping something in a circular afterimage
and so on...

And of course I've been throwing in some physiological diplopia and antisuppression exercises, because life would be boring with without them.

Thoughts on esotropia (and scotomas)

Sometimes, I lay awake at night, thinking of esotropia and how mysterious it is. I've read and heard over and over that exotropia is easier to treat than esotropia. Good thing I'm exotropic, I think to myself. But then I remember that I used to be very esotropic. I was a cross eyed baby! I had congenital/infantile esotropia. That's how this whole strabismus mess started.

I developed exotropia after my first surgery, and then a second and third surgery couldn't get rid of it. Is it really true that, because my strabismus surgeries accidentally made me exotropic, I now have a better prognosis than my esotrope friends? Even though my original condition was esotropia? That seems weird to me. Or lucky. Or something.

Perhaps it's all a mystery, and nobody knows...

After my previous post on suppression scotomas, I got interested in drawing out the suppression scotomas of esotropes. So here goes.

Both eyes are able to see the diamond, one centrally and one peripherally, and double vision should result because the eyes are not aligned. However, only one diamond is seen, because the peripheral diamond image is falling on a suppression scotoma.

In my previous post, I also mentioned that I had a habit of peeking around my suppression scotoma by overconverging. Is it possible for an esotrope to peek around their suppression scotoma? Yes!

If both eyes overdiverge and fixate on a point behind the diamond, that would make the diamond image fall outside of the suppression scotoma (and the image would double). However, this is easier said that done. I have trouble diverging my eyes at will, and I can imagine that an esotrope would have the same difficulty. After all, if they could diverge their eyes like that, they wouldn't be cross eyed! So it's possible that this may not happen as often.

It does explain something interesting, though. I am an exotrope, and I have trouble with physiological diplopia in front of the image I am fixating on. This is the kind of diplopia that happens when you put a pencil in front of your face, and make it double while looking at your professor. And when looking at the Brock string, I tend see an upright Y. I have trouble making the strings double in front of the bead. In both cases, the problem is the same: difficulty doubling in front.

My blogger friend Lynda, an esotrope, has the opposite problem. She has more trouble causing objects behind the image to double. While looking at a Brock string, she sees an upside down Y. She has trouble making the strings double behind the bead - difficulty doubling behind.

Both of our problems can be explained by looking at our suppression scotomas. As an exotrope, overconvergence causes images to fall outside of my suppression scotoma, and diplopia behind the fixation object is easier.

As an esotrope, Lynda would be the opposite. She probably has an easier time seeing diplopia by overdiverging, and thus seeing a double image in front of the object.

In conclusion, suppression scotomas explain everything in the world.

Better training mazes for Macula Integrity Tester

(Well, better according to me!)

The Macula Integrity Tester (MIT) is vision therapy device sold by Bernell. Through a phenomenon called "Haidinger's brush", this machine allows you to see exactly where your macula is pointing. When you look into the machine, you see the small Haidinger brush spinning at the exact spot your macula is pointing. It's pretty cool!

The MIT is usually used for treating eccentric fixation (a subject for another post), but I like to use the MIT for general eye control exercises for my jerky left eye. If the Haidiner brush jerks and jumps around, I know that my eye is doing the same thing. If it moves smoothly, I know that my eye is moving smoothly, too.

One activity for the MIT are these training mazes. You look into the MIT and move the Haidinger brush through the maze. For my purposes, I try to make the Haidinger brush move as smoothly through the maze as possible.

I don't really like the mazes that are available, though. They are what are know as "perfect" mazes. They have one and only one solution, and many dead ends.

A maze of this type offers a task: find the correct way out. However, it's not a difficult task and it's often too easy to see the solution. Very few, if any, of the dead end paths of the maze are ever actually traversed, and thus most of the maze is not used. Imagine you were going through this maze and you got to that branch right before the exit. Would you really ever say to yourself, "I see the exit right there, but I wonder what will happen if I turn left and explore this bit over here?" The maze appears to offer a good opportunity to practice eye tracking, but the activity is over too quickly because, again, most of the maze is not used. The maze doesn't deliver what it appears to promise! I would even find myself pretending to get lost in the maze and going down obvious dead end paths, just because I wanted more practice with eye tracking. But I don't want to pretend anymore! I want a better maze!

So I took an hour, played around with a maze making program called Daedalus, and came up with some better mazes. They are "unicursal" mazes, meaning that there is one path through the maze with no branches. Thus, the entire maze must be traversed in order to complete the maze. Every inch of the maze is used! Below is an example of an 8 x 8 maze, the same size used in the original maze above. See how much more eye tracking is required in the new maze? If you quantify it by distance traveled, here is the score. Old maze: 21, New maze: 64.

Compared to perfect mazes, unicursal mazes offer an opportunity to practice eye tracking at greater length. Some might say that I killed all the fun and interest of the maze by removing the "find the solution" element. However, my feeling is this: you can solve mazes any time you want, but you only get so much time to practice fixing your eyes with your optometrist's fancy expensive machine.

I made 8 mazes with increasing levels of complexity. To use these mazes, simply open the .pdf file provided below, print the mazes onto transparencies, cut them out, and throw them in your MIT (because everyone has one just lying around their house, right?). Enjoy!

Unicursal training mazes for the Macula Integrity Tester

Finding the midline

Strabismics have problems keeping their heads straight. I have talked about this before, and so has Lynda. We are forever tilting our heads.

I think it has something to do with how we internalize our midline. If you ask someone where the midline of their body is located, they will draw a line down the middle of their body, from nose to belly button. Both strabismics and non-strabismics know objectively where their physical midline is located. But in everyday life, strabismics tend to operate from where they subjectively feel like their midline is.

It's my theory that your subjective midline is determined by the center of your visual field. Normal-eyed people have a unified visual field, and the center of that visual field conveniently lines up with the center of the body.

Strabismics only use one eye, and the center of that visual field becomes their subjective midline. Unfortunately, their subjective midline doesn't line up with their actual midline. The strabismic operates from what feels like his midline, and the result is head tilting and weird posturing. A stabismic may appear as if he has angled himself oddly to look at you, but he has really only centered you in his visual field.

This may also explain why I am duck-footed. I'm an alternating strabismic, and my feet have pointed outward toward my two alternating midlines.

As Dr. Getz explains in Strabismus and Amblyopia, "The problem of strabismus is not strictly an ocular or eye muscle control problem. Most strabismics are strabismics from head to toe."

Suppression scotomas - and why I overconverge

Suppression scotomas... I've read about them before, but I didn't really find the subject all that interesting. There's a spot on your retina... where you suppress... or something... blah blah blah... who cares. It didn't really interest me. But last night, while doing my vision therapy homework, I suddenly understood suppression scotomas. And I also realized the reason why I often cross my eyes and overconverge when I'm doing vision therapy exercises.

First, what the heck is a suppression scotoma? A scotoma is an area of your retina where images are suppressed. If an image falls on a suppression scotoma, it is suppressed.

This is me, looking at a diamond. I can see the diamond just fine in my right eye. My left eye is being bad, and shooting off into nowhere. The diamond can still be seen peripherally by my left eye, though, and thus I should see two diamonds. But I don't see two diamonds. I only see one diamond. Why? Because the diamond image from my left eye is falling on a suppression scotoma.

The suppression scotoma is that big green spot. Everything that falls on that green spot is suppressed. This suppression scotoma has been custom made by my eyes and brain to prevent double vision. It perfectly fits the way that I use my eyes in every day life. Things in my central field of vision are suppressed, yet things in my left-hand peripheral field are still visible. I do not experience diplopia.

When I do vision therapy exercises, I desperately try to see the input from both eyes, but I have trouble because there's a big scotoma in the way. I need to break down that scotoma and start using that spot on my retina again. But sometimes... I cheat. I peek around the scotoma. How do I do that? Overconvergence!

In this picture, the dotted lines show where my eyes are pointing. They aren't pointing at the diamond, they are pointing in front of it. This causes the image of the diamond to fall outside of my central vision, and I see two diamonds. More importantly, it causes the image of the diamond to fall outside of my suppression scotoma. I receive input from both eyes (hurray!), but it's a diplopic, misaligned image (boo!). I believe this is why, when doing activities with the red/green glasses, I often see a misaligned image like this:

When I realized that I had been overconverging to peek around my suppression scotoma, I was amazed. Brains and eyes are so smart. And tricky. And lazy. And good at finding shortcuts.

Physiological diplopia (and a fun exercise to practice it!)

Physiological diplopia (phys dip) is "a normal phenomenon in which objects not within the area of fixation are seen as double" (source). When someone with normal vision focuses on an object, everything in front of the object appears double, and everything behind the object appears double. This usually goes unnoticed by most people, unless their attention is brought to it.

Interesting side note - if you google "physiological diplopia", you find that many people have accidentally noticed their physiological diplopia, become incredibly concerned, and posted on internet message boards looking for a cure. Here's an example:

I only just found out there is a name for my double-vision, "binocular-diplopia". I am 17 years old and all my life have had a double-vision thing going on with my eyes. I didn't realise there was any problem until I recently looked into it online, discovering the description of this problem fits the description of diplopia. If I cover one eye, it goes away. This goes for both eyes. When I focus on an onject I see it as one, but whatever is behind it it doubled. What I need to know is how serious this can be for me... I have had no previous medical problems with my eyes, or with my head at all, so it has not been caused by any kind of tumors, etc. Basically i'm not sure what to do about this, I haven't told my parents about it. Should I see an eye-doctor of some kind? Please guide me on what I should do...(source)

I've also read that it's not uncommon for ophthalmologists to get a few patients like the one above in their offices from time to time.

Physiological diplopia differs from pathological diplopia. Pathological diplopia is diplopia that results from an abnormality in the visual system, such as strabismus. When someone with strabismus complains of double vision, it's because their eyes are misaligned and pointing in different directions.

If you have strabismus, you don't have physiological diplopia. It takes two eyes pointing at the same thing, and not suppressing, to get physiological diplopia. For a strabismic, developing the ability to achieve and notice physiological diplopia is a great thing. Why? Because physiological diplopia is an excellent way to determine if one is using both eyes, and pointing both eyes at the same place.

This is why we use the Brock string. The Brock string is a physiological diplopia exercise. When you fixate on a bead on the Brock string, the string doubles in front of and behind the bead. It forms an X. This is the normal response that we strabbies are trying to achieve.

I mentioned in a previous post that I had a little trouble with the Brock string. Instead of an X, I would see a Y.

I could see the double image behind the object I was looking at, but I would suppress the double vision in front of the object and only see one string. With practice, I got much better at seeing the X. However, when doing less controlled physiological diplopia activities, I was still terrible at it.

Hold your finger in front of your face. Look at your finger. Your finger should be in focus, and objects in the background should appear double. This has always been pretty easy for me. It's the next trick that is really hard.

Hold your finger in front of your face. Look past your finger, and look at something on the wall. If you do it right, your finger will double. I can't do it, though! It's too hard!

So, I have invented an exercise to help me practice physiological diplopa in free space. My vision therapist really liked it, so I decided to share it. Here it is!

Josh's Special Red/Green Diplopia Exercise of Fun

First, you need targets to fixate on, and the targets must be able to cancel with red/green glasses. Why? Because then you will know for sure if you are actually pointing both eyes at the target. (I often think I'm pointing both eyes at a target, but really I'm only pointing one eye at a target.) I made a hand-held target, and targets for the wall.

 

You also need red/green glasses (of course) and a pen light.

Instructions for diplopia in front of the target
Look at the target (either in your hand or on the wall), and place the pen light between yourself and the target. Focus on the target, and try to make the pen light double around the target. If you do it correctly, there will be two pen lights, one red and one green, around the target.

You can make this activity more "task-y" if you place multiple targets on the wall, and make the pen light double around each of the targets.

Instructions for diplopia behind the target
Hold the pen light in one hand, and hold the hand-held target in the other hand. Place the hand-held target between yourself and the penlight. Focus on the target, and try to make the pen light double behind the target.

End of Instructions

Once you acquire the ability to notice and see physiological diplopia, you can use it to determine if you are pointing both eyes at the same place and not suppressing. For example: you are at school, listening to a lecture by your professor, and you want to practice pointing both eyes at your professor. Hold a pencil close to your eyes, and try to make the pencil appear on both sides of your professors face.

You can also practice this while reading, which I have seen called "bar reading" or "wire reading." Just hold something (a pencil, a wire, etc) between yourself and the book you are reading. Try to make the wire double and straddle the page or the words that you are reading.

My vision therapist told me about an exercise that she likes where the patient must hold a bendy straw in his or her mouth, with the bent part up.

In Guiding Strabismus Therapy, by Lora McGraw (It's a great book! You can find it here), I even saw a physiological diplopia device that could be attached to your glasses. It's called "The Beak", and allows a hands-free (but weird looking) physical diplopia check. I love it!

In conclusion, physiological diplopia is very fun and useful, and there are lots of ways to practice it. Try it out!