I think it's related to my ADHD. Reading is very difficult because as I read, my voice just completely wanders off, CONSTANTLY. "Oh hey, 'gargantuan' that's a great word. Reminds me of a video game monster... Oh did you just read 2 whole pages without absorbing a single bit of it?"
To add a bit more commentary: this is the one time I consider my ADHD to be a terrible disability. I cannot read. I just can't. Grad school was HELL when I had to read. But my ADHD and associated strong independent inner monologue is immensely powerful when I'm trying to solve problems myself, such as doing software design.