As well as heart function is to pump blood and lungs are oxygen tanks and kidneys are filters and each organ has an amazingly coordinated function, brain also has the main function that is keeping us alive. Based on these criterion, the brain makes all its decisions: what does consciously and what not, that filters and showing that recalls that it forgets, and chemistry to develop in the body, etc. Etc. The brain has an area dedicated to the unconscious and instinctive functions and an area dedicated to conscious functions. The area destined to the unconscious functions have to be incredibly faster than intended for conscious functions. Imagine that by putting your hand on a hot stove, outside the conscious part that would protect us. It would first analyze the situation, consequences, and possible options, before removing the hand of the danger. Fortunately it doesn’t work as well and is the unconscious which obliges us to act in fractions of a second and move away from the danger.
Conclusion? The unconscious is incredibly fast and more dominant than the conscious. Psychologists say that the first years of our life, especially the first six, are decisive and that the experiences, schedules verbal, the observations that we have performed and the patterns of conduct and beliefs from our parents and other authority figures, have been recorded at very deep levels. And if the models of our parents and our environment were poverty, we have inherited them. If their models were from disease, that we have inherited. If they were of mistrust toward other people, that we have inherited. The human brain tends to move away from the displacer or which is contrary to the pleasure or what perceives danger and then (understand later) seeks pleasure. Therefore maintains in the foreground what does not want or which may cause danger and only then focuses on what you want.