Visual Processing Dysfunction


Q: I have a post concussion patient who reports visual and auditory hallucinations. Can you speak to why and how lack of ambient processing leads to hallucinations?


Answer:

“Hallucinations are interesting and I discovered it indirectly. And I began to understand it because when treating patients with hallucinations, I began to have the effect of the hallucinations would disappear. Give an example. I was at a hospital where I gave a speech, a grand round, similar to what I just gave to you. And after the presentation, I was approached by the psychologist, the OT and the PT that said, “I’ve got to see this patient before I leave,” I went off to another room, and they brought this man in. He was in a wheelchair, and he was screaming “get him off me and get him off me.” And he was literally flicking at his arms and trying to swipe away at these things, that he was hallucinating. I started talking with him and I said, “Well, what are you seeing?” And he said, “I’m seeing these brown, green things there they’re coming at me.”

Well, it just so happened that the rug was filled with giant brownish greenish pine cones. I recognized he had post-trauma vision syndrome after a brief screening. And I took prisms, placed them on his face, and within two minutes he sat back and I asked him what happened to the monsters, and he said they were gone. A week later, I was called in my office because I left him with some prism glasses, and the psychologist PT and OT were on the line. And they asked me if I remembered that patient, I said I did. And they said, since I had given them the prism prescription, he hadn’t hallucinated. And they were bringing the psychiatrist back in to see if they could take them off of the psychotropic drugs. What happens there is that when the focalization process locks onto a detail and you lose the plasticity for allowing you to make a change of movement with your eyes, any movement of your eye gets projected out into what you’re looking at.

For this gentleman, as he was looking at the rug pattern, if he moved his eye or his body, he projected that movement out. The movement of these patterns, then he began to interpret differently in terms of, not just the pine cone, but something alive. I’ve had patients where a lally column, or a vertical line on a wall, suddenly turned into a giant snake that was slithering down the wall and coming at them. Treat them for the PTVS, and suddenly that becomes stable, and they no longer see it as a snake. So hallucinations are there because of a projection of movement, usually by the person through either their eye movements or body movements, the visual process projects that movement into the environment. And they interpret as something like a monster that had giant bugs on pizza pies, which were nothing more than pepperoni. Monsters jumping into pools after people which were vertical lines, a lot of strange responses.”

Faculty:

William Padula, OD & Charlie Shearer, OD

Q: How can a physical therapist tell if a patient is over focalized in their examination?


Answer:

“So if they’re over focalized and you don’t know that, and you have them start to track, I’m going to see if I can get a closeup of my eye movements. When they start to track, a normal tracking will appear like this, where the spatial process literally anticipates the change and focalization is maintained on the target. If you go into over focalization, you literally become locked into a time and space, so that you’re going to see this happen. So what’s occurring is they fixate, the target is moved, they lose the anticipation for the change. They’re still stuck here and then make a quick eye movement, a saccade over to the next point. So when you see these patients and they’re having jerky eye movements and fixation losses, this isn’t a muscle problem. What it is, it’s an imbalance in the spatial process, not anticipating the change.

Same thing will happen with a saccade. So you have two targets just as you saw the young girl before to make a shift from one point in space to another point in space requires the release of the fixation. You go into a high trajectory movement, and you don’t see the world during that high trajectory movement. Because the extra ocular muscles sent up to the brain that their eyes are in high velocity and a shearing effect occurs where the focal process is shut off. Yet the spatial processes never shut off because it’s mapped and it’ll deliver you to the next point of fixation, even though you’re not seeing the world move. With patients that have over focalization and no release to focalization, when they make a quick shift of their eyes, they’re going to be shifting their eyes and not making it accurately, just like I’m doing in front of the camera. So when you see inaccurate shifts, when you see that they get stuck on a point and they can’t release from that point and it takes them time to get to the next fixation point, these are all characteristics of focal binding.”

Faculty:

William Padula, OD & Charlie Shearer, OD

Q: Are there strategies to help patients with motion sickness get to their appointments without provoking symptoms?


Answer:

“Absolutely. That is a great question because that’s how many of the patients come in through the institute here in Connecticut. Well, one way is to get them to a neuro-optometrist to make sure. So let us treat these types of conditions by prescribing the right amount of prism. However, sometimes this isn’t possible. So binasal occlusion on glasses is very important. So you can have, if they’re wearing glasses, have them take two pieces of tape, black tape preferably, and place it in the corner of both lenses. I’ll get closer to the camera here.

So about a half-inch wide, the greater the symptoms, the wider the binasal occlusion. Never cover an eye. Only cover the binasal component of the lens. If they don’t have glasses, take a pair of sunglasses, even cheap ones from a store, and pop out the lens, and then put binasal occlusion on the frame. It’s a temporary fix. It’s not going to solve the problem. And if they wear this binasal occlusion continuously without the prisms, the brain is just going to get used to it, so the symptoms are going to come back.

Some other things that I found helped patients, tell them rather than sitting on a very comfortable, soft seat to get a board or some hard seat to sit on in the car, even a backrest that has more firm support. The firmness helps support the base of support and helps organize the proprioception.

For some of these patients, if they have a steering wheel and they’re driving the car, if they’re in control and are making fixation changes in relationship to where they want the car going, the symptoms are far less. But if they’re sitting in the passenger’s seat, they’re now passive. Have them take a book and literally steer the car.

So if they’re driving, make all the adjustments that he would normally to the steering wheel that they feel the car is making. And when the car is in a turn, literally have them turn the book and look in the direction of the turn of the car. All of these factors help kick in kinesthetic and proprioceptive support to stabilize the spatial-visual process.”

Faculty:

William Padula, OD & Charlie Shearer, OD

Q: What is visual binding?


Answer:

“Certainly, you have two aspects of the visual process, as we discussed. The focal process wants to literally lock onto detail, and it says balance from the spatial process, which was developmentally the first process that was established in the hierarchy of our development. It’s this balance that constantly causes us not to jam down on just detail.

When that spatial process gets compromised from a concussion, whether it’s a trauma to the head, or whether it’s from a whiplash, what can occur is that it leaves the focal process without any type of balance, without any type of check and balance. So, the focal process knows no other way, other than to work harder, to try to achieve its goal. And when it works harder to try to achieve its goal, it literally becomes bound onto all aspects of detail, not just in your central site, but your whole world turns into detail. And if there’s movement of that detail, it becomes chaotic.

And that is what leads to many of the symptoms that people have when they go into a busy, crowded environment, such as they feel overwhelmed or overstimulated, and it also produces conditions of noise factors that they no longer can take what might be normal noise. Even the noise level seems to be increased.

It’s more than seeing. The spacial visual process is preconscious, not in the sense that you’re seeing now. So, as you look across the room and you see your visual field, you have to realize that that’s one visual process and what’s balancing out and causing you not to see the periphery as just a lot of detail is that the spatial process blends off this information, so that the focal process can concentrate through the fovea or macula area.

However, you can use the focal process in any portion of the field that you want. So, if I would hold my finger up like this and concentrate on my finger with my peripheral vision, that’s a focalization. We can do that, but it takes more energy to run focalization through the peripheral process.

So, it’ll diminish in its intensity as a detail on a few moments. It’s this balance that the spatial process always tries to maintain peripheral organization and provide the central focal process isolation for the point of fixation. And it’s the balance that enables release of the focalization to the next fixation point.”

Faculty:

William Padula, OD & Charlie Shearer, OD



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FACULTY BIOs:

William Padula, OD

William V. Padula, OD is Director of the Padula Institute of Vision Rehabilitation in Guilford, CT. He is the Founding President of the Neuro-Optometric Rehabilitation Association (NORA) and Senior Fellow of the National Academy of Practice Dr. Padula is an Associate Professor at Salus University of Health Sciences College of Optometry in Philadelphia, PA and is an Adjunct Professor at Western University of Health Sciences College of Optometry in Los Angeles, CA. He is the Founding Chairperson of the American Optometric Association Vision Rehabilitation Section. Dr. Padula has been a consultant to the National Academy of Sciences Committee of Vision. Research has been conducted by Dr. Padula discovering Post Trauma Vision Syndrome (PTVS) and Visual Midline Shift Syndrome (VMSS). Dr. Padula also served as the National Consultant in Low Vision Services for the American Foundation for the Blind and Director of Vision Research to the Gesell Institute of Human Development.

Charlie Shearer, OD

Charlie Shearer, OD has been a nationally recognized leader in the areas of vision therapy, visually related learning problems and sports vision enhancement. He has worked with US Olympic athletes and teams, professional and amateur athletes, and coordinated national screening of both Special Olympics and Junior Olympics. Charlie is a leader in the field of instrumentation development as related to his role of Vision Science Consultant for Bertec Corporation, as well as his work with other companies. Charlie was born in Mishawaka, Indiana. He received his undergraduate and optometry degrees from Indiana University. When Charlie returned to Mishawaka, he resumed care of the patients of retiring Dr. Lou Fishman. Soon after, Charlie relocated his practice with Jonathan Kintner, OD.