That Neuroscience Guy - Optimizing Your Vision with Special Guest Dr. Cameron McCrodan

Episode Date: October 6, 2023

Vision is more than just your eyes - you need your brain to intake visual information and process it. However, optometric care has largely focused on treating just your eyes. But what if we started trying to change your brain instead of your eyes?  In today's episode of That Neuroscience Guy, we invite Dr. Cameron McCrodan to discuss how targeting visual processing and control in the brain can markedly improve treatments for patients with concussions, migraines, balance issues, and more. 

My name is Olof Krogolsen, and I'm a neuroscientist at the University of Victoria. And in my spare time, I'm that neuroscience guy. Welcome to the podcast. All right, so today we have a guest, Dr. Cameron McCrodden. He's a really interesting guy. He went from engineering to optometry and now back to engineering and he runs a company called Optimization. Now, if you've had a concussion or you know someone who struggles with reading, maybe they experience dizziness or migraines or they're just someone that does a lot

of reading or computer work or that's even you, you're going to find this really interesting because there's a new model of vision that can help deal with these things. It's basically about looking at how the eyes and brain work together within all these various problems. So like, for example, with a migraine, you know, what's going on with the eyes, but also what's going on within the brain. So if you think about, you know, the sort of problem areas that are out there, you know, this is a new way to address these things and think of ways to either remedy it or provide some relief. So Cam, thank you so much for being on and welcome to the podcast. Thanks for having me on. Long time fan. Happy to be here. Well, thanks, Cam. I'm a fan of yours. I actually got, in the

interest of full disclosure, I got my latest two pairs of glasses from Cam because I trust what he does so much that I'm willing to trust him with my eyes. So engineering and optometry, how does that fit together? Can you tell us more about that? Yeah, it's kind of interesting. Growing up, I always wanted to be an engineer and love designing in the way that things work and then wound up falling out of love with engineering as I went through it, got into optometry. So now I basically deal with the engineering of optometry because my brain still thinks like an engineer. I'm always interested in the why and the how and the mechanisms. And so essentially it's like we always interested in the why and the how and the mechanisms. And so,

you know, essentially it's like we deal with how the eyes and the brain work together now. It's like the software that runs what your eyes do and decodes it and integrates it with all your other systems. That, that makes total sense. And I guess, I guess what I experienced with, when I was within your clinic, you know, last week is there were some tests that we did that I wouldn't say that I've experienced them ever before. And I guess that's getting at the brain side of this? Absolutely. So vision is such an interesting sense in that it's not passive the way that we always think about it. So when we're actually examining how things are working, we actually want to look at how you're using your vision. You know, how accurately

do you judge where things are? How accurately do you coordinate eye movements? How accurately do you integrate your vision for depth perception, balance, and other things too? So when we're testing those things we're going well beyond testing just how clear things are that you see or what prescription you need to see it. But we want to actually see how well does your system perform and are there ways to enhance that? Or could any of those performance deficits be interfering with your quality of life or your work capacity, etc? That makes total sense because I know like for me, I just use myself as a first example,

is I thought my distance vision was fine but then my eyes weren't seeing things quite the way they're supposed to so that's that's an example of that i guess well absolutely and you know a lot of people are affected by this because again our human visual system hasn't really evolved to deal with the visual demands of our modern life you know for much of the human history not know, their reading hasn't been around in the majority of the population for a long time. Neither has extended, you know, staring up close. And so even myself, you know, when I was in university, I used to, after like three pages of studying, I'd kind of lose focus and I'd be like, I just read that paragraph and I'd have to go back and reread it or make myself a tea or grab some food. I had no idea that my eyes actually had an inefficiency

with how they moved when I read and it made it significantly harder for me to sustain my focus and concentrate. Nobody picked it up, not even when I was at optometry school. But so that's a perfect example too of I could see clear, see it fine. However, there were inefficiencies in the coordination of my movements that made it harder to focus and sustain concentration. I want to walk through that a bit more. And I have to admit, you've hooked me on personal interests. So I remember you told me about the fact that, you know, maybe you're reading slower than you should or struggling to read. And I kind of chuckled and went, yeah, yeah, no, I read every day. You know, it's part of my job.

And then sure enough, I put on a pair of glasses and next thing you know, I can literally tell I'm reading faster. So just what, and I think reading better, you know, I don't know how much of that is subjective, but in my mind, honestly, for the past week, I feel like I'm reading things one time as opposed to going back and starting again. So what is happening there? Well, first I have to say, Olav, you're wonderfully unique, but the things you just reported are not.

That's actually some of the most common feedback. And so, I mean, what is happening there is a couple of things. So in the act of reading, for example, you know, most of us just think, OK, our eyes just kind of see it. But in reality, when you're reading visually, your brain needs to calculate where is the next word on the page? You know, how far away is that? How much of a motor response do I need to make with the eyes? It needs to coordinate the eyes together to both land in the same spot. It's got to keep your focusing mechanism at the right depth of the page. And all of this is like a fine-tuned system of both, you know,

the processing and then the actual motor control. And inefficiencies in that system mean that as you're going, you have to keep readjusting. I can liken the difference to, and you may get this now that you've experienced it, it's like the difference between driving a car down the highway with beautiful wheel alignment that you just don't even have to think of. You point and go versus, you know, like driving a 1970s van down the highway where you're constantly steering just to keep it straight, you know, and then there's all of the kind of levels in between that. that. So what happens, you know, and what we're really digging into now is when it doesn't work as well as it should, there's actually a lot of conscious effort and cognitive power that your brain then has to use to keep readjusting your eyes as you go. And the more effort you're having to put into read, the harder it is to actually be attentive and have your attention on what you're reading rather than the act of reading itself. And if you think about that in terms of like other tasks, for

example, you know, the first time you learned to drive or drive standard, it'd be very hard to pay attention to conversation or a lecture on the radio. Once driving works smooth and efficiently and you're not having to pay much attention to it, you can actually really attend to something else and digest that information. And reading is much the same way. So the glasses, for example, that we sometimes prescribe aren't necessarily just to make it clear, but they may actually serve the purpose

of stabilizing the focusing mechanism or stabilizing how the eyes move together or even changing your perception of where the next word is on the page so your motor movement actually goes to the right place and you're not constantly readjusting. You know, it's like a wheel alignment for your eyes when you're reading. That's, I find this fascinating because, don't take this personally, but prior to meeting you, I'd gone to a different optometrist and all they ever did was make things clear. None of this was ever discussed. So I think it's really cool. I think the other

thing that makes me sad too is, you know, I've been a neuroscientist for closing in on 20 years in some form or another. And we just sort of ignore the motor part of this. So when we talk about vision, you know, it starts with light hitting the back of the eye, but we never really talk about, you know, just coordinating the eyes or this kind of stuff. So I find this personally fascinating. Now let's dive into something that's a bit more, you know, this is reading,

but what about someone that's had a concussion? So, so can you give us an example of like what you would do to help someone with a concussion? Well, that's a, that's a good area and it's a hot topic. And I think it's often important that we get the definitions correct for things too, because this is actually where there's a lot of controversy. Because sometimes people will be like, okay, treating vision does nothing to help with concussion. And I would say, absolutely, unless the concussion has caused problems with vision. So, you know, just to be super clear, when we're treating vision, we're not necessarily treating the, you know, just the concussion or symptoms of the concussion, but in the cases where vision has been disrupted. So when we do get injury to the brain,

it can disrupt the axonal connections in the brain that are responsible for, you know, basically controlling and processing our vision. Now, given the fact that over 50% of your brain is involved in vision in some form or another, you know, it's not simply just kind of the occipital lobe processing everything. There's a, it's very, very likely that after concussion that vision does get disrupted. So really the job for us after concussion is, hey, what symptoms is somebody having? And then you very, you know, carefully and objectively measure their areas of visual function to see if anything in relation to those symptoms is impacted or not. And then if it is, do you have ways of fixing it? And this in a nutshell is sort of the engineering meets optometry. Because in standard clinical care

within med school, optometry school, dental school, the model that we're taught for helping people is generally you come in, we do our tests, we make the diagnosis based on our tests, and then we do what the book says for the diagnosis. The engineering approach to things usually is going, okay, explain to me the problems that we're having, you know, or if we're seeking to optimize something and make it work better, but explain to me what the situation is. if we're seeking to optimize something and make it work better, but explain to me what's what the situation is. Let's test the systems that we know that could be responsible for that. Anything that's not working the way it should, then let's figure out, do we have ways to make it work better? So commonly after concussion, things like depth perception can be impacted,

how the eye, how well the eyes work together can be impacted, how the visual and vestibular or inner ear systems work together can be impacted, which can visual and vestibular or inner ear systems work together can be impacted, which can lead to everything from light sensitivity, headaches, migraines, difficulty reading and focusing is a big one. The amount of family members I've had who've been significantly impacted by that is significant and it's one of the reasons that I care so much about what I do. So really in a nutshell after concussion, the job of somebody who works in this area of the optometrist who deals with how the eyes and brain work together is to really measure and see if

the concussions caused any deficits to visual function and if those deficits are getting in the way of the person's recovery. Because a lot of other concussion rehabilitation actually needs the vision to work properly for the other rehab to be successful. If someone's doing vestibular rehab a lot of other concussion rehabilitation actually needs the vision to work properly for the other rehab to be successful. If someone's doing vestibular rehab, a lot of the time they're, they need their vision to work properly for it. Or if they're doing cognitive rehab, they need it to work properly for that. And so that's, that's really the role that we play. So it's not, it's not so much treating concussion as it is treating the vision problems that may be caused by concussion. And again, that's where a lot of academic arguments come in fair enough and i and i guess that would

be true of we you know with the one of the examples we had at the outset was dizziness so if my dizziness is caused by a visual deficit or a problem with vision that would be something that you could potentially address right absolutely and you have no idea how common this is. So, I mean, I think you may have mentioned experiencing it yourself, but the way that we're taught to prescribe glasses and lenses and even make them is all about clearness with little thought given to how does that prescription actually impact somebody's depth perception and their orientation in space. This is why so many people hate their glasses or are uncomfortable with their glasses because while they've been given for clearness, they actually disrupt the person's spatial perception. And there are so many people walking around where that's happening to them.

It's actually remarkable. So yes, there's ways that we can improve dizziness and other symptoms like that again if it's related to how the vision is working that totally makes sense and we talked about migraines two seasons ago i've got a good friend marla mickleborough she's a professor at usask and she did more of like what's going on in the brain but we didn't talk about migraines and a lot of people write in and you know migraines are out there. I luckily don't experience them. But migraines and vision, it's a similar sort of thing, I'm guessing, where if someone has migraines and there's visual issues that might trigger them, that's again where, you know, you would come in with what your approach? fortunate to actually work with a multidisciplinary team around migraines, like really fortunate. Our sister clinic, the Health League, has an MD managing it and a few other great professionals. So being part of that group, I've learned a phenomenal amount. And so, yes, where we come in is looking

at the visual contributors of migraine. And this all started sort of years back when people would report, you know, one of the easiest ways to tell if migraine, and this is for the listeners too, this is an easy way to tell if your migraines or headaches are triggered by vision. If you look at that pattern glare, you know, we'll have what we're looking at running with the EEG with. So if you look at the pattern glare, those black and white lines, and it feels like that could trigger a headache or migraine for you, well, then we know vision is part of the problem. Because, you know, it's like giving someone a peanut and they have a reaction. It's like, all right, well, we know peanuts are part of your problem. And so then from that point, the goal is how do we get their vision to work better so that they are less sensitive to those things? And that's what we see when their vision works properly. They're going to be a lot less sensitive to those visual stimulus. Is that always

the whole reason for their migraine? Absolutely not. People are entitled to more than one problem. But you know, if the migraine is the cup that when it flows over, that's when you get the migraine, what we want to do is reduce how much vision is contributing to that cup. And it's often a huge one when you talk to migrainers, they'll explain their visual sensitivities, their light sensitivities. They want to close their eyes, be in a dark room, et cetera, et cetera. I think the percentage of patients that we see presenting with migraine, now mind you, our patients are rather self-selecting because we are a visual clinic, but the percentage we see presenting with migraine

where vision's not at least a part of it is very low. That makes total sense to me. And for the listeners, our blog is kind of sporadic, but I promise before this episode airs, I will put up the pattern glare image on the blog. So thatneuroscienceguy.com, find the blog, and you can see the pattern glare that we're talking about. And I can assure you that the first time I saw it,

I kind of went, yeah, yeah, and then all of a sudden felt uncomfortable. So it's worth checking out. So we've kind of answered one of the questions I was going to ask you, which is why does it matter? Because I think everyone that's listening can figure out why it matters unless you got something to add. I mean, I'd say a huge reason that this stuff matters is it's about 80% of kids who are struggling with reading who actually have deficits with how their eyes move, track, or work together. And again, I've had family members in that situation, and I've seen what it's done to their lives. You know, just two weeks ago, I had a patient where we put glasses on her that changed how her eyes tracked and moved. She was in grade 12 and she actually just started bawling in that second saying to her mom, this is what I've been trying to tell people for the last 10 years. And she'd been to eye exams every year, but they hadn't looked at how her eyes

actually tracked and worked together. You know, the amount of people I see on long-term disability, not able to work because the visual components of their concussion or the vision problems that they're now having after a vestibular problem like a neuritis were keeping them from working. You know, they couldn't tolerate screens, they'd be dizzy, they'd be getting headaches, and nobody had checked how their vision worked. So the reason this is important is societally, not only, I mean, there's a lot of personal suffering happening that doesn't necessarily need to be there you know people could be performing a lot better in general and suffering a lot less so if you lived on Vancouver Island I would say and these problems are stuff you're experiencing you'd go to optimization but if you live off of Vancouver Island like how do people

know what what they can look for there actually are quite a few practitioners out there who work in this area. And the best thing that they can look for is an optometrist who often is trained by or affiliated with COVD or the College of Optometrists and Vision Development or Vision Therapy Canada, or sometimes different organizations in their country. But most importantly, find an optometrist local to them who measures how their eyes track, how they work together, has experience in vision therapy, understands that, and has experience in utilizing and prescribing glasses in ways that actually improve how the vision works as opposed to just for clarity. adjust for clarity. So, you know, and that's something that not a lot of people realize is that just as well as glasses can actually mess with depth perception and mess with eye movement and those things, you can actually use it in ways to enhance those things and improve those things as well. Yeah, that's a good tip because obviously it's impossible for us to search the entire world

and list all these people, but those are very tangible things that people can look for. I always like to ask this question too. I mentioned this, you know, before we started recording, but I think everyone has stereotypes about how people get to their career. But, so how did you get to where you are? What's the, what's the, what's the, the brief version of the life story that got you to running optimization? Well, the story in a nutshell was again, me wanting to be a kid and invent things and design things that would help a lot of people and change the world. And getting into engineering and getting a little disheartened after my first year with that, leaving engineering, I was going to go to law school, med school or dental school and settled into optometry school. Optometry seemed

happy. Quite frankly, when I got out of optometry, I was actually really, really bored. The engineer part of me, I wanted to be solving more complex things and doing things with a lot of meaning. So I was actually going to quit optometry and go back to dental school because I thought if I'm going to be unhappy in my work, I'll make a lot more money being unhappy in my work and then I don't have to work as much. But truth be told, a friend of mine introduced me to this area and I realized very quickly that, A, not only was this actually the engineering of our vision, but it was also something that was grossly overlooked. And then when I realized that my sister had struggled with these issues for so many years, you know, and I saw what it kind of did to her in that sense, you know,

then it became personal. And, you know, I helped her with her eyes in her mid-20s and we got that dealt with. And then she went back and did her MBA. And I can remember her saying, you know, is this how everybody has read their entire life? Like, is this how most people have read? They can read something once and remember it. You know, they don't have to continuously go over it, try to make notes 50 different ways, read it out loud. She's like, they can just read it and remember it. You know, they don't have to continuously go over it, try to make notes 50 different ways, read it out loud. She's like, they can just read it and remember it. And I'm like, yep, that's how it works for lots of people. So that's kind of what led me to here.

And, you know, I'll tell you and my patients will too. I mean, if I won the lottery, Olav, I would still do what I'm doing now. I just wouldn't have to worry about my mortgage. But, you know, the piece behind it now is it's much more of a cause and a mission than necessarily just sort of a career. You know, my goal is I want to change how the world understands these things and make sure that it's addressed at every level for everybody. Well, I can understand that. It's always great when you find a career like that. I was just telling someone the other

day that if I won the lottery, I'd still be a neuroscientist. I'd just find someone else to grade midterm exams. That might be the one thing I'd change. All right. So Cam, just as we wrap up here, if people want to know more, you also have a book and a TED Talk, which I've watched. I have to admit, I haven't read your book yet, but now I definitely am going to. Can you tell us a bit how people can find these things? What they're about? The irony of having a book that is often aimed at helping out people who don't like reading. There is an audio version of it on YouTube and probably coming soon to Spotify too.

But there isn't, they can't, people can download a digital copy of our book on our website, which will be in the blog links as well. And the TEDx talk I did in 2014 in Victoria called Overlooking Our Vision. It is on YouTube and it is on our website. It's only 10 minutes. You know, if you know, the TEDx is really geared towards the reading and learning side of things. So if you have a child in school, if you know somebody in school or you know a teacher, that talk can give so much more empathy

and understanding towards kids who are struggling with these things and knowing how to spot it. As a former teacher, I don't know if I've told everybody, but as a teacher before I went back to school, I found the TEDx talk fascinating. I was really into it.

Well, Kim, thank you so much for giving us a bit of your time. This has been fascinating. I always love it when I do something like this and I'm more excited about it than when I started because now I just want to go read more about vision tracking and stuff. So thank you so much for being on the podcast.

It's an absolute honor to be here. Thank you, Olaf. Great. Well, everyone, remember the show notes and the blog stuff will be up on the blog i will post stuff with the grading and some links to uh cam's book and to his tedx talk so it's all there for you remember that's that neuroscience guy.com there's links to our uh blog obviously but links to our etsy store and to patreon where everyone can support us. And remember on X, I am at that neuroscience guy. Please send in ideas. We still have a lot of season left to go and we're always looking for new ideas. And finally, thank you so much for

listening to the podcast and subscribing. My name is Olof Kregolsen and I'm that neuroscience guy. I'll see you soon for another neuroscience bite.