Tuesday, March 27, 2012

RevitalVision Renews My Vision

Who'd have thunk that staring at fuzzy patches in the dark would help your eyesight?

As my Gentle Readers know, I have been working on my eyesight for quite some time.  I have plateaued a bit in the past couple of weeks.  No new posts lately on how the world has been changing.  No new delights have been noticed for quite some time.

I think that is about to change.

Some real aspects of seeing blobs
Some real aspects of seeing blobs (Photo credit: doylesaylor)
One of my problems is intermittent suppression with my left eye.  I have cursed that bad boy on and off.  I have begged for it to turn on and stay on.  If I don't get two eyes working, by definition I won't get too far in eye teaming exercises or stereo vision.  When I was doing Cellfield, I noticed that I was having problems seeing some of the exercises involving grey print on white and red on red.  I also have noticed doing some of the vision therapy exercises that I have been having problems with suppression as well.   I end up blinking my eyes rapidly or flapping my hand in front of my left eye to wake it up.  I do much better with antisupression glasses.   Sometimes I put anti suppression lenses on for the first few trials of the Brock String to wake up the eye as I do my home exercises.

I began to wonder if contrast sensitivity is at the root of my problems with suppression.   So I went off to Long Island and got the program, RevitalVision, and am doing the section on ambylopia (lazy eye).   I've done 16 sessions so far and it is starting to really help.

RevitalVision involves 40 minutes of using your week eye staring at a variety of fuzzy patches that gradually get fainter and fainter.   These fuzzy patches are Gabor patches.  For the mathematically inclined, Gabor patches are patches of Gabor filters, a linear filters whose impulse response is defined by a harmonic function (sinusoid) multiplied by a Gaussian function. Gabor filters  relate the wavelength of the sinusoidal factor,  the orientation,  phase offset, the sigma of the Gaussian envelope and  the spatial aspect ratio (ellipticity of the support of the Gabor function).
Visueel systeem
Visueel systeem (Photo credit: Wikipedia)

Gabor filters are used in image recognition, iris scans and face recognition systems to help match similar  images, irises or faces.

Gabor filters are significant because they are thought to model the activity of the simple cells in the primary visual cortex (V1).    There is a bit of controversy on this hypothesis from a study by researchers at Stanford who have found that in many cases receptive-field functions other than Gabor functions fit better.

Even if there are better mathematical representations of the visual cortex than a Gabor function, I have been finding that my eyesight has improved by doing Revital Vision.  RevitalVision isn't the most interesting program.  Imagine sitting in a darkened room just looking at fuzzy patches getting fuzzier.  I have fallen asleep at nights in the middle of the program.  I get tired and need a break so I lie down.  The next thing I know is that it's one o'clock in the morning.  Sometimes I've continued the program in the wee hours.  Other days, I do it first thing in the morning.  That seems to work better.  I do 3 exercises and then take a rest and do 2 sets of 3 or 4 more exercises till I have finished my sessions.   The only other thing is that the program makes you take a break for 20 hours between sessions so if I forget to sign off completely, I miss a whole day of practice.  I do wish the tutorial had some help with getting better at the exercise but I do find that my vision is improving nonetheless.

After 16 sessions, I am finding that I can see a whole lot more detail and a lot more  in the world around me.  I can see wood grain in my furniture a lot more sharply.  Siding on houses looks sharply defined, i.e. a clear line between siding strips instead of a fuzzy blur.  I am getting a better sense of space because objects around me are better defined.

Also,  my stereo vision has improved and when I think about it I can see more of the world in 3 dimensions.  My husband and I took a drive the other night and I made him do a U turn as the Bradford Pear trees stood out as 3D pyramids.  I was shouting, "The Trees, The Trees!!!"

Hubby humored his strange wife as he knew his time to become strange with vision therapy would be soon approaching!  We are a matched set.  Who knew!

Copyright © 2010-2011 Traveller Journey Through The Cortex