Third metaphoric layer of the brain

The neocortex, which evolved relatively recently, is located on the surface of the brain. Proportionally, this level occupies more space in the brains of primates than in those of other animal species. Cognition, memory storage, sensory processing, abstraction, philosophy, self-reflection — all reside here.

Read a terrifying passage in a book, and level 3 will signal level 2 to make you feel fear, which in turn will instruct level 1 to initiate trembling. Watch an Oreo commercial, and you’ll feel the urge to eat it — that’s level 3 influencing levels 2 and 1.

Think about the fact that your loved ones (or children in a refugee camp) won’t live forever, or that the tree of the Na’vi in Avatar was destroyed by those awful humans (even though — wait, the Na’vi aren’t real!), and level 3 will engage levels 2 and 1, making you feel sorrow, with a stress response as if you were running from a lion.