We tend to think of ourselves as free autonomous conscious entities. We are human, and that makes us stand out. To my mind this is an oversimplistic view of reality.
As mammals evolved into primates the brain evolved too. But the principle of evolution being that existing systems are being extended, that caused additional brains to spring from the original basic brain, the brainstem, to take up the extra load.
All vertebrates have a brainstem like structure. It is the minimum needed to keep the body going. Nutrition, oxygenation, temperature, movement etc. are regulated by the brainstem.
With the evolution of the mammals a second outcrop started to develop. The limbic system.
The connection between the limbic system and the brainstem is a mostly one way system in the sense that both brains can interact with the body but not with each other. The two brains are fused together at the bottom of the brainstem into the spinal cord. This gives the limbic system corporal control,in conjunction with the more automated brainstem.
It is a much more advanced brain which handles various higher order processes, such as survival tactics. Survival depends on properly recognizing danger, food, procreation opportunities.
This takes advanced planning, decision making, fast responses to stimuli. This brain interacts with its environment, it must be aware of itself and its relation to its environment to do the job properly.
In other words it is conscious at a certain level.
As mammals further developed into social beings, a new outcrop started to form. The neocortex.
This third brain again has mostly one-way connections with the other two brains. It also fuses into the spinal cord giving it further control over corporal functions. The neocortex houses the most advanced processes,it refines all functions of the limbic system and adds the high order intellectual capacity, such grammatical language, self awareness.
In view of the very limited vertical connections between the neocortex and the underlying limbic system, and taken the fact that the limbic system has priority in determining danger/food/procreation in its environment one can see that the neocortex always by necessity reacts after the fact.
The limbic system perceives danger, it prepares the body for the fight/flight response and the neocortex takes this up afterwards due to a complicated interpretative analyses of facial expression (the limbic system has control over that), body stance, muscle tension, heart rate, respiration,hormone levels and lastly visual and auditory clues.
In most cases where immediate action is deemed necessary by the limbic system it performs the required action, leaving the neocortex to figure out why the body landed a blow in someones face.
This gives rise to the thesis that ‘our’ consciousness is just along for the ride. Although ‘we’ can plan and act accordingly, when it comes to real-time environmental interaction its our other consciousness which calls the shots.
This has far reaching consequences for the premise of ‘free will’. Who has the free will, which consciousness we hold accountable. Or do we just hold the one accountable which can make itself heard even though in reality that consciousness actually hasn’t a clue why his body did what it did and has to concoct an explanation itself.
It also places emotions. Emotions are not ‘our’ emotions but the expression of the state of the other consciousness which for lack of further interaction the neocortex also has to determine via interpretative analysis.
Which leaves ofcourse the facility to plan and (re)act based on cognitive functions. One still can decide to do X or Y. Still this decision making process is being manipulated.
To my mind this whole system is best explained with this analogue:
Imagine that our awareness is the flow across the Collector and Emitter of a Transistor. The Base in this analogue is the limbic system, tiny fluctuations can have a big effect on our storyteller.
This works well also to explain the difference between low and highly emotional people.
A transistor has a specific gain, that is how much the Base current influences the Collector/Emitter flow. With the same Base current you can have a big influence or small influence depending on that gain.
As such we are totally at the mercy of our limbic system, but in some it shows more then others.
Food for thought.