My boyfriend was also diagnosed with schizophrenia and he scored high on an IQ test, even though he has really bad concentration problems. He can't follow plots of movies and he has to re-read passages constantly when he is reading a book. He also needs to edit everything he writes for a long time.

(I also happen to have a high IQ and my concentration is not great.)

So, I wouldn't say that there's a strong connection there. Besides, from what you are writing, it doesn't sound like you have any intellectual deficiencies.

Have you tried any supplements like Omega3, ginko, ginseng... that could improve concentration? Or do you feel more focused when you rest more or are less stressed? Or is it always the same?

I wonder what it feels like to not be able to follow a plot of the movie; my boyfriend looks like he's following, then it turns out he has no idea what is going on. I think his mind can be very active and creative and he has many associations so he is constantly getting distracted. Everything reminds him of something else, so his trains of thoughts are very fast and branch out in all directions.