My parents were distraught to learn that I was probably developmentally disabled, for my teacher had noticed that I didn't distinguish between words presented in the "correct" orientation or in other orientations.

They were relieved to discover the actual situation wasn't so bad: it wasn't so much that I was potentially dyslexic as that I liked reading so much I was willing to forgive amazing (to the school staff) variation in presentation.

And, over the years, ability to read upside-down has occasionally proved commercially useful.