well i think that human mind is actually formed from parts that are like different people in one mind. but are totally unaware of each others being like different people and that only one of them can be conscious at time and when they communicate with each other. the receiving part sees the info coming in as if it were generated by that particular part of self, instead of seeing the info as something that someone else said. and that the parts are able to go from conscious to unconscious and back to conscious so fast that its impossible to notice it, and sometimes one part might use more "conscious time" working on some particular thing than other parts. and that personality forms from how much conscious time you prefer to give to particular parts of the brain and naturally from your past experiences etc.
so i think its fair to speak about different functions as if they were different persons(or different 'selves'), since those functions are basically areas of the brain(or group of brain regions) that tend to work together or form these functions when working together.
maybe the unconscious thinking/perceiving comes from not using some parts of the brain long enough or doing enough processing thinking in that thing thats being processed?