It could be suggested that consciousness is simply an internal state of the mind, within the physical brain itself. This would seem to be a common sense assumption if we regard the mind as a ‘Turing Machine’ all be it a very complex one. However this assumption can be challenged when we begin to think about how the machine is programed.
When a brain first forms it must suddenly begin to be able to change it’s own internal state – a form of self programing using the available data. Admittedly this will at first will be very limited, but remember the built in ‘operating system’ is as old as the evolution of human kind and all of our ‘thoughtful’ ancestors. Upon birth an immediate cascade of information flows into the brain via the senses and continues uninterrupted until death.
Although there are wide varieties of sensory input, the main interaction is a flow of information between brains, language being the main carrier of this data. Every human mind creates levels of simulation of the other minds it communicates with in tandem with it own functions. The prerequisite for consciousness does not solely depend on a complex set of interactions within the mind of one individual, rather it is the presence of other minds in the immediate sensory environment. A mind is only conscious of itself because it is conscious of other minds.