My eyes have been awful since I was a kid, but just near-sighted. My daughter needed vision therapy as a young child, and when I went into the therapist's office, I got an exam for my glasses prescription.
Turned out that I had similar issues, just not noticeable. It had to do with my eyes not being able to properly maintain a focus at a specific distance over time, and their ability to track properly. I've always been a slow reader - this is at least partly why. I was told that it's also responsible for the fact that I get car sick within seconds of reading in the car, and that it goes away with therapy. Unfortunately, I never did go through with the therapy.
Turned out that I had similar issues, just not noticeable. It had to do with my eyes not being able to properly maintain a focus at a specific distance over time, and their ability to track properly. I've always been a slow reader - this is at least partly why. I was told that it's also responsible for the fact that I get car sick within seconds of reading in the car, and that it goes away with therapy. Unfortunately, I never did go through with the therapy.