5-minute read

The Last Time We Were Together

In the last post we talked about how the brain notices — the 1/10th of a second amygdala flag, the cocktail party effect, and how trauma cranks the noticing dial to 11.

If you missed it, catch up here 👉 👀Part 1: How Does The Brain Notice?

This post is about what happens next.

The brain noticed something. Now it has to figure out what to do about it.

☕ The Coffee Date That Wasn't What She Thought

Lisa Feldman Barrett was in grad school when a guy in her psychology program asked her out for coffee.

She wasn't particularly interested. Wasn't her type. Agreed mostly to be polite.

But as they sat across from each other in the café, something strange happened. Her face flushed. Her stomach began to flutter. Her heart started beating faster. She had trouble concentrating on what he was saying.

Oh, I guess I am attracted to him, she thought and so she agreed to a second date.

Then, hours later, she vomited, cuz she had the flu.

The flushed face, fluttering stomach, racing heart — none of it was really attraction. It was actually a virus.

Her brain had noticed the internal signals and then decided what they meant — but it decided wrong.

Welcome to this month's second question: How does the brain decide?

🫀 Interoception: Sensing Inside Your Own Body

Lisa Feldman Barrett's research introduces a word your students need (and you do too): interoception — sensing the body's internal signals.

Right now, your brain is listening to your stomach, your heart, your lungs, your muscles. It’s a constant stream of data from inside your body.

Most of the time you don't notice it. But every signal gets weighed, interpreted, and turned into meaning based on context.

The brain doesn't passively receive signals. It decides what they mean — based on context, history, and what it expects to be true.

Barrett's flu-date wasn't a glitch. It was the brain working exactly as designed: take the body's signal, run it through the current situation (a date 💕), and produce an interpretation (attraction).

Same signals, different context, completely different interpretation.

Your Boss Walking Toward Your Desk 👀

Here's another Barrett story that's absolute gold.

Imagine your boss is walking toward your desk. She doesn't say anything. Doesn't do anything. She's just walking.

Your heart rate ticks up. Stomach tightens. Cortisol releases. Glucose floods your bloodstream.

Why? Because your brain predicted something important might happen. You might need energy. You might need to defend yourself. You might need to act quickly or strategically. The brain made a decision about what this signal meant — based on every prior interaction with this person. 

Now imagine your favorite coworker walks toward your desk. Same physical reality (a person, walking). Completely different interpretation and physical reaction (anticipation, relief, ease).

Translation for the classroom: When you walk toward a student, their brain is already deciding what your approach means — based on every prior interaction.

A student who's been called out repeatedly may have a body that decides you're a threat before you've even said a word.

Not because they're being difficult. Because their brain learned teacher/adult in charge means threat. 🧠

🧠 The PFC (Thinking Brain) Steps In

We've talked about the 😎 PFC thinking brain before — the part of the brain that helps us slow down, weigh options, stay chill and make considered choices.

But sometimes the PFC is disabled.

In 1848, a railroad foreman named Phineas Gage was pounding explosives into rock when a spark ignited the powder. A 3-ft rod blasted through his cheekbone, behind his eye, and out the top of his skull — taking most of his frontal cortex with it.

Phineas holding the rod.

He survived. He stood up. He walked to the doctor. 🤯

But the Phineas Gage who survived wasn't the same man. The polite, hardworking foreman became impulsive, profane, sexually inappropriate, unable to hold a job. His friends said he was "no longer Gage."

Without his frontal cortex, his brain could still notice and interact with stuff around him. 

His amygdala still flagged threats. His dopamine network flagged rewards. His body still gave him signals. But the “intelligent deciding” part — the slow, considered, "wait, is this a good idea?" part — was no longer there.

Decisions can be made without the 😎PFC thinking brain, they’re just going to be more primal, impulsive, aggressive, and emotional. If the PFC thinking brain isn’t deciding than the 🧟 Survival Brain is. 

For our students we have to consider that 1.) children don’t have fully developed PFC’s and 2.) under stress the little PFC they do have often goes offline. Survival brain takes the wheel 🚗. Same way as if Phineas Gage himself were sitting in that desk.

Student reactions to seemingly benign things begin to resemble big fight/flight behaviors.

🛜 Dopamine: The "This Matters" Signal

Here's where dopamine comes in.

Dopamine doesn't make you feel pleasure. That's the old story.

Dopamine signals "this matters" — it tells the brain "pay attention, learn this, do it again."

In The Power of Habit, Charles Duhigg tells the story of his 3:30 p.m. cookie craving 🍪. Every afternoon, like clockwork, he'd walk to the cafeteria and buy a cookie. He thought he craved sugar.

He didn't.

When he forced himself to walk to a coworker's desk and chat for 10 minutes instead, the craving disappeared. The cookie wasn't the reward. Social connection was. His brain had been releasing dopamine at 3:30 not for sugar — but for the social moment that came with the cookie purchase.

His brain had decided social connection mattered. And dopamine kept driving him back.

Translation for the classroom: When a student seems "addicted" to a behavior — calling out, getting laughs, picking a fight — their brain has decided something about that behavior matters. There's a dopamine reward in there somewhere.

You can't just remove the behavior. You have to find the reward the brain decided it needs. 🔍

🛟 If You're Using The Toolkit

A student isn't just reacting. Their brain is deciding — every second — what signals mean and what to do next.

Your job? Make the deciding easier.

From the Behavior & Needs Detective:

• Use the Interview Questions (Sensory, Anxiety, Executive Function, Confidence, Belonging, Physical Needs) to figure out what the brain is deciding about your room, your tone, your approach.
• Run the Student Needs Checklist — when the brain is deciding "this isn't safe," it's almost always one of the 5 NEEDS (Safety, Comfort, Autonomy, Belonging, Competency) that's compromised.

From the Instruction Kit:

• Predictability is the brain's security blanket 🛌. When students know what's coming, the PFC doesn't have to spend its budget on threat scanning — it can spend it on learning.
• Cue Chunk Chew + Soft Starts give the brain time to decide it's safe before you ask it to think hard.
• The "Task instead of Ask" move means you're giving the brain a clear, low-cost decision instead of an open-ended ask that requires more PFC fuel than it has.

From the Classroom Environment Kit:

• This is where Conscious Classroom Management lives. The "owner's manual" for your room. Every routine, every transition, every spatial choice is telling the brain what to decide.
• The What Are Your Triggers? reflection is for you. If your dysregulation is in the room, the students' brains are deciding it's a threat — even if you think you're hiding it.

Don't have The Neurodivergent Toolkit yet? 👉 [HERE]

Closing Thought 🍃

Noticing is fast. Deciding is slower. And what the brain decides depends on:

• 🫀 The body's internal signals (interoception)
• 🌍 The context the brain is interpreting them in
• 🧠 Whether the PFC has enough resources to weigh options
• 🛜 What dopamine has flagged as important in the past

A student isn't just reacting. Their brain is deciding — every second.

When you understand that, you stop asking "Why did they do that?" and start asking "What did their brain just decide, and what's it deciding based on?"

That's the whole job. 💪

Next month, we go deeper: How does the brain learn what's important in the first place? That's where prediction error, salience, and one very famous monkey enter the story. 🐒

Citations

• Feldman Barrett, L. (2017). How Emotions Are Made: The Secret Life of the Brain. Houghton Mifflin Harcourt.
• Sapolsky, R. M. (2017). Behave: The Biology of Humans at Our Best and Worst. Penguin Press.
• Harlow, J. M. (1868). Recovery from the passage of an iron tamping-rod through the head. Massachusetts Medical Society Publications, 2, 327–347.
• Duhigg, C. (2012). The Power of Habit: Why We Do What We Do in Life and Business. Random House.