In my teenage years I was inspired into trying creative photography after being impressed by an article entitled "Imagine an image and print it". The ability of human beings to imagine something and turn it into action is difficult to explain in terms of pre determined chemical activity over which we have no control.
I don't find that sort of thing difficult to explain at all, I'd like to think I've done the equivalent repeatedly in this thread. What I think you mean is that YOU find it difficult to explain, partly because you find it difficult to accept. That doesn't mean that it's wrong (any more than my finding it easy to accept makes it right).
There must be something within each human being which perceives and manipulates thoughts and optionally turns them into action.
It's called a brain.
This "something" can aptly be named the human soul.
Why would we hypothesise a soul when we have more than enough evidence to show that the brain both is involved in this, and is sufficient to explain this?
No doubt the non believers will be able to dream up ever more complex scenarios of neurological brain activity which will explain everything, but this is just further evidence for the inventiveness inspired and driven be the non deterministic forces of the human soul.
So the fact that we can answer your question, to you, is evidence that we're wrong and can't answer your question...
O.