So it is with our triune brain. The paleo-mammalian brain, the limbic system, the emotional centre (the physical centre of the brain, too) develops in the womb, and stores our affective and implicit memories.
The neo-cortex, develops when we enter the 'outside' world, at birth, and isn't fully formed until after adolescence: it is the the seat of awareness, language and reasoning: of social organisation.
The brainstem and hindbrain, are legacies of our reptilian past: they regulate our most basic functions, and are the source of rage and lust.
We need all of these areas, of course, and all such subdivisions are over-simplified, of course.
BUT...
Remember that you were born with feeling, with love and empathy, and not much more than those, mentally. Your self-consciousness, your ego, formed later, as the neocortex grew - as you learned the rules of your society, and how safe you were within it.
Some of us had to block out our emotional core completely, as we tried to fit in with the crazy rules of a crazy family, religion or nation... forever to become organised machines with no access to a human heart. Some were so neglected or abused that organisation failed them, and they became no more than reptiles... taking what they could from the world by force, full of dread and terror when not on the attack, alone in the universe. A fortunate few were nurtured sufficiently during development, and their thoughts were tempered by love from the core, their instincts could be satisfied without harming those around them.
