I often talk about our “old brain” and our “new brain” — how the habit formation and reward circuitry parts of our brain evolved a long time ago, while the rational, thinking parts of our brain are relatively recent additions to our repertoire of human skills.
Nobel Prize winner Daniel Kahneman also outlines two distinct systems in our brain that he calls “System 1” and “System 2.” In his book, Thinking, Fast and Slow, Kahneman describes how System 1 is the “fast” system, responsible for quick reactions, snap decisions, and intuition, while System 2 is responsible for the slower, more deliberative approach. Sounds a bit like the difference between our old brain (“see tiger, run fast!”) and our new brain (“let’s go see the tigers in the zoo this weekend, and maybe have brunch afterwards?”), doesn’t it?
I recommend reading the entire book, but this short overview of the brain regions involved is a quick primer.
