The Triune Brain

The lowest (oldest) channel termed reptilian immersed in the fight or flight aspects of survival, the mammalian "limbic system" associated with emotions, pleasure and pain. And the highest most recently developed portion called the neo (new)cortex. The trick to being effective and successful in life is to maximize top down input from the neocortex to the limbic system and restricting "limbic hijacking" ..

By Ben Fuchs | Pharmacist Ben

Triune BrainOne powerful way to look at our lives and experiences, is to divide our the input channels into our brain into 3 parts (the so-called triune brain model proposed by Paul MacLean). The lowest (oldest) channel termed reptilian immersed in the fight or flight aspects of survival, the mammalian “limbic system” associated with emotions, pleasure and pain. And the highest most recently developed portion called the neo (new)cortex.

The trick to being effective and successful in life is to maximize top down input from the neocortex to the limbic system and restricting “limbic hijacking” i.e bottom up input from what are not truly life-threatening situations.
 
Wikipedia: The neocortex, also called the neopallium and isocortex, is the part of the mammalian brain involved in higher-order brain functions such as sensory perception, cognition, generation of motor commands, spatial reasoning and language.

The neocortex is further subdivided into the true isocortex and the proisocortex.

In the human brain, the neocortex is the largest part of the cerebral cortex which is the outer layer of the cerebrum, with the allocortex making up the rest. The neocortex is made up of six layers, labelled from the outermost inwards, I to VI. Of all the mammals studied to date (including humans), a species of oceanic dolphin known as the long-finned pilot whale has been found to have the most neocortical neurons.