No change that I can tell regarding intelligence. But then, do stupid people know they're stupid?
But, before I had excellent spatial relationship abilities. It use to throw me off talking to my ex regarding directions. We would be at home and she would be using her hands pointing in directions as she was giving me directions to some place. She would ALWAYS point the OPPOSITE direction on every direction she was giving. Her brain seemed to work in reverse regarding maps and directions. I would get confused by this and she would get angry with me, but I am (or was) more visual, but she needed her hand jesters to help her with her thought process, but we were like the three stooges (or two of them anyway) on getting places on time.
I noticed shortly after HRT that I was standing in my family room and I couldn't think of what streets went which way or anything. It was weird, it wasn't backwards, it just wasn't there at all. So, I do feel there can be an affect on our brains, it probably depends on the individual.