I was on meds on and off for about a year with no change. Then I went onto a depot of clopixol which meant I was compliant with meds, about four months later my head started to clear. When you've been so determined you are correct about a certain thing it doesn't just go away overnight. I would imagine some of it is biological and helped by the meds but I would say it's personality based as well, it can be hard to give up on such an idea that has been a big part of your life.