There are many ways to divide the brain into parts, depending on what you're discussing. For our purposes, there are three parts that concern us:
- the reptilian complex
- the limbic system
- the neocortex
We'll do the easy one first. The neocortex is the big gray part. It's over 80% of the brain, and it deals with language, creativity, logical thought, formal operational thought (which, you will recall, none of our students are developmentally capable, darn them), and foresight (no comment).
The reptilian complex is the oldest part of our brain.
It's at the back, near the bottom, and it's in charge of a lot of our behavior. It handles all the automatic stuff like digestion, reproduction, circulation, and breathing. It also handles our gut-level survival-oriented decision-making, aka "fight or flight."
Its behaviors are automatic, have a ritualistic quality, and are highly resistant to change.
For example:
Territoriality: "He's sitting in my chair!"
Preening: Ever watch 5th grade boys tuck in their shirts around a bunch of 5th grade girls? Or watch a high school senior run a comb through his hair?
Nesting: Ever see my desk?
Maintaining social hierarchies: "We don't want you to sit with us."
Mating rituals: One year, I had a young man in my class who was so beautiful it hurt to look at him. On the days he wore his black t-shirt, I could not get the attention of the girls in the class for love or money.
Flocking behaviors: Why does your child have to have that kind of shoe? Because everyone else does.
Isopraxic behaviors: That's when members of a group communicate by doing the same thing, like high-five signs, gang signs, catchphrases, etc. Remember when you could "tell" someone was gay by which ear he had pierced?
Perseverative and reenactment behaviors: Strict adherence to inflexible routine, ritual; strict conformity to precedent. If a behavior is successful even once, it is likely to be repeated, even if surrounding circumstances have changed drastically. For example, what if lecturing like a medieval monk worked for medieval monks? Would we still be talking at the children 800 years later even if that method really didn't work? "But we've always done it that way!"
Tropistic behaviors: Growth pattern behaviors. Barney is cool, then Dragonball-Z, then Gundam Wing Fighters, then MTV, etc., etc.
Deceptive behaviors: Lying, cheating, stealing, bragging, etc.