In particular something that I want to call your attention to, the only region that showed activation proportional to the mental changes that we could measure was V1 so this is a primary visual area, this is not supposed to be involved in anything when you have your eyes closed still we found that when people have their eyes closed and they are trying to imagine, V1 is as active as if the person had the eyes open, so when people say I'm seeing things, it's not a joke they are, they are seeing it as vividly as if they had their eyes open 