I'm glad I found someone who mentioned this as I was going to. I've spent the first month and a half of my summer reading books (4 down, which is more than I've read in the past decade and a half combined) and I definitely feel as though it has helped me focus more. I've been more disciplined about really "reading aloud" the words in my head as opposed to when I was younger I kinda just skimmed and didn't really take in what I was saying.

Edit: should say outside of assigned readings for school work. Which tend to lean technical and are never fully read from cover to cover.