What is the mechanism by which information processing produces conscious awareness of that information processing and/or the result of such information processing?
In essesence, how does a human think to itself: "I am thinking"
First, there's the internal dialogue, generated in the temporal cortex, that allows us to reflect on something, basically separating our "selves" from the thing we are contemplating.
http://cogprints.org/3784/
Now, take the statement in parts:
"I" is something we learn about over time. Think of the first time a child sees a mirror, how long before they realize that the image of a person they see is themselves. They've identified other simliar looking figures as entities that provide food, nurturing, entertainment, etc. The child realizes they are a similar entity, quite different from a chew toy or that stupid hard coffee table. Overtime, they understand how to communicate with the other entities, and realize that the other entities must be quite like themselves. They understand that they are separate from walls, their clothes, and everything else. They can see their own body and understand that they have control over some parts of the body (hands, feet, head). Self is defined relative to what is not self, and the nature of self is learned as the child learns about other humans and how those humans compare to self.
"am" is a word that is learned to mean "being" in a passive sense.
"thinking" is a word attributed to when people use what they experience or learn to give better understanding of some aspect of themselves or the world around them.
"I am thinking" is understanding self through life experiences as doing the act of using experiences and knowledge to formulate a new experience or new knowledge.
Atoms don't do this. Plants don't do this. Animals have only shown the ability to understand self in a rudimentary fashion (dog's know their name and probably realize they are a dog and not a tree). Gorillas with language skills might have the realization that they think as they learn the words humans endeavour to teach them, but we don't know yet.
How does a brain come to realize it is thinking? Storing information and processing that information to make new information that it can use to process with more additional information obtained through sensory perception. Artificial intelligence has not accomplished this feat as of yet. The human brain has.