The eyes have it

I hope I'm not stepping on Janie's post, I'm always grateful to her for keeping the home fires lit, but this article caught my eye as it were and I thought I'd put up, in large part because it lets me talk about what's ailing me (and maybe some of you?)

https://www.sciencealert.com/your-vision-can-predict-dementia-12-years-before-diagnosis-study-finds

Our research was based on 8,623 healthy people in Norfolk, England, who were followed up for many years. By the end of the study, 537 participants had developed dementia, so we could see what factors might have preceded this diagnosis.

 

At the start of the study, we asked participants to take a visual sensitivity test. For the test, they had to press a button as soon as they saw a triangle forming in a field of moving dots. People who would develop dementia were much slower to see this triangle on the screen than people who would remain without dementia.

 

So why might that be?

 

Visual issues may be an early indicator of cognitive decline as the toxic amyloid plaques associated with Alzheimer's disease may first affect areas of the brain associated with vision, with parts of the brain associated with memory becoming damaged as the disease progresses. So vision tests may find deficits before memory tests do.

I can't help but feel like there is a correlation/causation problem here. Couldn't it be that loss of visual acuity itself be a factor in Alzheimer's? The assumption is that the amyloid plaques are affecting visual acuity, which is taken as a sign, but it could be that if your eyes get worse, that might be the/a causative factor?

Cause as you get old, your vision certainly gets worse. This link has a useful list and it seems to me that rather than thinking that Alzheimer's is screwing up your eyes, it might be the other way around. Or at least enough to not make pronouncements about plaques and inhibitory controls.

I tend to think this cause I can feel that my worsening eyesight as well as my experiences with my vision suggest that the vision causes problems for memory.

I was the first kid to get glasses in my elementary school. My 2nd grade teacher told my mom at the end of the year conference that she thought I needed glasses because I was doing poorly on math tests not because my calculations were wrong but because I was writing down the wrong starting numbers. My mom thought that was crazy until one day during summer vacation, one of our neighbors, an officer in the Air Force, was coming to our house and I told my mom that the plumber was coming.

I got glasses and, in an experience common to people like me, it was astonishing because it was the first time I could see individual leaves on the tree. Another interesting thing was that my memories, for the most part, start when I got glasses. I can't do it now, but well into my 40's, I could remember everyone in my elementary school classes. Back then, glasses took you off the sports track, at least for contact sports like football. I did judo as a kid, and while not being able to see very well can help you with balance and being able to react, I was unable to visually learn, which seems to be a really important way for me. I got to be even more of a book worm, and could often remember where on the page a particular passage was.

Fast forward to language learning, I thought I was quite good at languages, doing French, Latin and Greek at uni and then going to Japan. I don't want to spend too much time in the weeds, but after 5 years in Japan, my Japanese was ok and I worked pretty hard on reading. It was just as the computer revolution was starting and I purchased a Fujitsu Oasys word processor because Japanese on the computer was rather tortured. I went to grad school and got interested in endangered languages, so took Thai, imagining I could do fieldwork in Thai. With grad school, I didn't do any Japanese reading, but when I got a job at Hokkaido University, I unboxed the stuff I had sent from Japan to rebox it to send back to Japan (Some of you may know this drill) and I came about my Fujitsu Oasys word processor. I plugged it in, opened it up and was greeted with a 3 page essay that I had written. I could remember typing it out, where I was sitting, a whole wealth of details, but I couldn't read what I had written. I could figure out characters, and piece it together, but I might have just been typing the Japanese equivalent of Redrum.

Getting back to Japan, I had a job with a fixed term and after three years, I again packed up my stuff to ship down to Southern Japan. At that time, I found my Thai notebooks and this time, it was even worse. I couldn't make heads or tails out of stuff that I had written. It made me realize that a lot of my language ability was tied up in roman letters. If I had gone with Vietnamese, I probably would have been a lot better off.

Fast forward to about 10 years ago when I had to have emergency surgery for a detached retina. It wasn't because of a punch or a car crash, apparently, the vitreous (the clear fluid that fills your eye) turns to a more gelatin like consistency and in shrinking, it can pull the retina from the back of the eye. I had the surgery, but afterwards, I found that I had lost about 10 or 20 meters off my vision in terms of recognizing faces. This wouldn't be a big deal, but before the operation, I could recognize someone who was my student and in the time that it would take to close the distance between us, I could dredge up their name. Losing that distance meant that I had less time to figure out who it was and would often draw a blank. In the past ten years, I can tell that this inability has impinged on me remembering student names and placing them in context.

Now, my father had alzheimer's, but his was probably because he was a college boxer (strangely enough, his eyesight was probably as bad as mine, but he still boxed) So I don't think these holes in my memory are because of some genetic disposition towards alzheimers, it is more having an increasing number of holes in my knowledge base and therefore, lose ground because of losing the context.

There is an interesting cultural aspect to this. Asians are known for having poor eyesight, and it is not just an ignorant trope from Breakfast at Tiffany's, but an actual issue for East Asian countries. I like this podcast, which I started watching because of the insights into TSMC, which is building two factories near me, and this episode about the issues with myopia in China and what they are doing to deal with it

https://www.youtube.com/watch?v=3YWbR8K0jT4&t=42s

While the push to deal with myopia in China is more because of the ocular health, but I wonder if people like me will decline more quickly because of this. At any rate, talk about your eyes or whatever else ails you.

 

Comments

[JanieM]

Lots of juicy stuff here, which I hope to come back to when I get some quiet time. But for now...

1. I read only the first bit of the first linked article, then skimmed the rest. There does seem to be a lot of almost-presuming-the-conclusion speculation. But in relation to lj's quoted passage, I don't read it as suggesting causation, but rather prediction, which is different.

2. A couple of years ago a friend sent me this article (sorry for not embedding):

https://www.dailykos.com/stories/2022/7/22/2111914/-Two-decades-of-Alzheimer-s-research-may-be-based-on-deliberate-fraud-that-has-cost-millions-of-lives?utm_campaign=trending

Not surprisingly, it's a bit overblown in its own way in commenting on research described more thoroughly here:

https://www.science.org/content/article/potential-fabrication-research-images-threatens-key-theory-alzheimers-disease

Since those articles are from 2022, I went looking for later developments and found these write-ups:

https://www.alzheimers.org.uk/for-researchers/explaining-amyloid-research-study-controversy

https://www.alzheimers.org.uk/for-researchers/explaining-amyloid-research-study-controversy

Complicated stuff, obviously, and as a lay person with very little time to spend digging, I don't know if people are partly (or mostly) protecting turf and reputation, or what.

My dad was diagnosed with Alzheimer's in his late fifties. He died at 71 after several years in a nursing home. He couldn't sit up on his own, he couldn't speak, he had some strokes, he had a feeding tube.

His autopsy revealed that he didn't have any signs of Alzheimer's at all, he had MS (late onset). A correct diagnosis in the first place wouldn't have made much if any difference in the possibility of treatment, but the sequence of events does reveal -- again -- how complicated this topic is, and how fraught with uncertainties.

*****

I too am very visual. I take in information by reading, not by listening. Podcasts do nothing for me. Listening to someone read a card in Magic: The Gathering when I played with my kids did nothing for me; I had to read the card for myself. As to non-Roman alphabets, well....maybe later.

[Girl from the North Country]

I got glasses and, in an experience common to people like me, it was astonishing because it was the first time I could see individual leaves on the tree.

This made me smile sadly, because I remembered when my beloved father eventually succumbed to family pressure, and got a hearing aid (in his 70s, so really, too late in the long term - plus they weren't that good then), and when we went outside for the first time with him wearing it, he grabbed my arm in alarm, and said "What's that noise?!", and I had to say to him "Daddy, it's the wind..."

[wj]

I got glasses and, in an experience common to people like me, it was astonishing because it was the first time I could see individual leaves on the tree.

I was in high school when we realized I was near sighted (20/400 plus astigmatism). I had never been able to see the blackboard; didn't realize that wasn't normal. But I listen well. Got glasses in college -- couldn't skate on ears and brains there.

I do wonder why a simple vision test wasn't standard for first graders. Is it now?

[liberal japonicus]

thanks all and especially Janie. I may be reading into it too much, but there seemed to be this underlying assumption that vision is a constant. I can sadly assure you that it is not...

[JanieM]

Me: I take in information by reading, not by listening. Podcasts do nothing for me. Listening to someone read a card in Magic: The Gathering when I played with my kids did nothing for me; I had to read the card for myself.

This is exaggerated. In reality, it's just that I take in information more efficiently and reliably by reading/seeing than by listening/hearing.

*****

Agreed that vision is not a constant. If nothing else, I can measure that by the regularity with which my glasses prescriptions have changed as I've gotten older. And I too have a childhood story: I realized in fifth grade that if I closed one eye and then the other, one eye could see the blackboard okay, the other saw fuzz. I told my mother, who thought I just wanted glasses because my best friend had recently gotten them.

[Snarki, child of Loki]

GftNC: and I had to say to him "Daddy, it's the wind..."

very touching story. Thank you for sharing it.

[wj]

I take in information more efficiently and reliably by reading/seeing than by listening/hearing.

I find that I absorb details, and deep understanding, far better by reading.

But if I'm primarily looking to absorb general background, get familiar with terms (preparing to get their exact meaning later), etc. listening actually works somewhat better.

[wonkie]

I think humans are very oriented to visual learning, far me than listening. Perhaps this is part of our genetic history as pack-forming territorial hunter/gatherers. In any case, my observation of other people is they miss most of what they hear unless there is an accompanying visual.

Oddly, I am a very good listener. My only problem with listening is that I have little patience with presentations that don't get right to the point.

I have become less visually adept over time, and I seriously suck at recognizing people. I also have a strong disinclination to deal with complex and boring processes that I used to take care of pretty efficiently. I do wonder if there's something cognitive going on with me.

On the other hand, I just finished a novella and am nearly done with another one.

Old age sucks.

[Michael Cain]

I saw the ophthalmologist last month. When she asked how my vision was doing, I told her I thought things had sharpened up over the last year. When the examination was done she said I was right, both distant and near vision were about three letters better. Due to strabismus when I was young, I have biocular vision rather than binocular and switch back and forth between eyes depending on where I'm looking. My left eye has a measurable vertical deviation when my right eye is "in charge." She also said the deviation was smaller than a year ago and the switch occurred more quickly.

This seems like a peculiar thing to happen to a 70-year-old.

[Girl from the North Country]

Thank you, Snarki. He is 24 years dead, and not a day goes by without my thinking of him.

[Snarki, child of Loki]

Vision is your highest bandwidth input channel. Typing is your highest bandwidth output channel.

Accuracy and retention is more individual, but oh yeah, want that bandwidth.