Your brain doesn’t erase fear.

It overwrites it with a fragile safety memory.
But that memory has to compete with the old fear.

That’s why fear can come back after therapy.
It’s not failure. It’s neuroscience. 🧵 2/ A new Nature study recorded from the human amygdala (the brain’s fear hub)

They found:
• Fear extinction = theta waves (a “safety signal”)
• But it’s context-bound = strong in the clinic, weak outside.

Safety and fear memories exist side by side, battling for control.

If dopamine = pleasure...

Then why does chocolate still taste good when it’s blocked?

Because dopamine isn’t about liking.
It’s about wanting and learning.

Let’s rewire how we think about the world's most popular neurochemical 🧵
2/ 1950s: scientists gave rats a lever linked to stimulate their brain.

The rats got obsessed.
Thousands of presses. No food. No sleep. Just zaps.
Humans did too.

That loop?
VTA → NAC → cortex
(mesocorticolimbic circuit)

Spouses don’t just share lives... they often share the same psychiatric disorder.

A study of 14.8M people found the pattern spans decades, countries, and kids.

They found that mental health is equal parts:
• personal
• relational
• generational

But why? 🧵 2/ So what's behind the trend?

Three forces at play:

• Assortative mating → “we choose people like us”
• Convergence → shared life makes partners more alike
• Stigma → dating pools narrow options

ADHD. OCD. BPD.

Often misunderstood + dismissed.

But what if these minds (too fast, too focused, too intense) are wired for originality?

Part 2: the hidden creative gifts of “chaotic” brains 🧵

https://twitter.com/1687216652130418691/status/1960325460677595604

2/ What does creativity look like?

🚫 You don’t get creative by thinking harder.
✅ You get creative by thinking differently.

Logic → frontal lobe
Wandering → default mode network (DMN)

New ideas happen when these two brain networks play well.

Why do so many brilliant artists also battle their minds?

Autism. Bipolar. Schizophrenia.

What looks like illness… often unlocks genius.
A thread on the strange link between brain disorders and creativity 🧵
2/ Creativity is less logic and more collisions of the unexpected

The process looks like this:
prepare → wait → "aha!"

The unconscious layer wanders and does not ask permission. It connects dots your conscious mind ignores.

Here's how it can show up 👇

Some smokers quit the day after a stroke.

No cravings.
No withdrawal.
No relapse.

Why do different brain injuries → same result → in one circuit?

Let's find out 🧵
[2/11] Most people think addiction = too much dopamine

reward gone wrong
weak willpower
yada yada...

But dozens of patients quit overnight after brain injury.
So what do strokes reveal that science missed?

So I'm getting asked alot:

"Why did GPT4o → 5 feel weird?"
"Are AI companions addictive?"
"Is AI addiction real?"

The answer is messy... but what’s happening IRL might surprise you 🧵
[2/10] AI companions ≠ psychosis

These can be different phenomena.

Companions (Replika) are designed for emotional connection.
In my clinical exp, psychosis cases usually involve general AI (ChatGPT) used during vulnerable states.

I’m a psychiatrist.

In 2025, I’ve seen 12 people hospitalized after losing touch with reality because of AI. Online, I’m seeing the same pattern.

Here’s what “AI psychosis” looks like, and why it’s spreading fast: 🧵 [2/12] Psychosis = a break from shared reality.

It shows up as:
• Disorganized thinking
• Fixed false beliefs (delusions)
• Seeing/hearing things that aren’t there (hallucinations)

Apathy is what happens when your dopamine system breaks down.

People call it laziness → they’re wrong

Here's what motivation looks under the hood, and how to fire it up again 🧵
[2/11] Most people think apathy = depression

But apathy isn’t sadness.
It’s the break down between thought → action.
Like turning the key in a car…and nothing happens.

10 Truths About ADHD You Don’t Want to Hear
(but might change how you see the world) 🧵
ADHD isn’t fake.

But it might not be what you think.

What if it’s not a brain disorder, but a mismatch between your wiring and your world?

Buckle up.

Let’s cut through the noise 👇

Everyone’s been saying psilocybin “rewires the brain.”

Cool. But where, exactly?

A new 2025 Nature study finally has the answer. And this could change how we treat depression. 🧵
[2/11] Most people think:

Psychedelics = “plasticity everywhere”
SSRIs = “serotonin everywhere”

But that’s not how the brain works.

Plasticity is:
• Circuit-specific
• Time-dependent
• Neither good nor bad by default

So which neurons actually matter?

Neuroplasticity = the brain’s ability to change. But plasticity itself isn't “good” or “bad.”

• High plasticity + good environment → growth
• Low plasticity + bad environment → stuck in depression

Here's how to unlock your plasticity 🧵
Critical periods are windows when your brain is primed to change.

What opens them? Hebbian learning.

• Neurons that fire together wire together
• Mistime the pattern → the window closes

This is how all neural networks (human or artificial) work.

In 2025, I have admitted 12 cases of psychosis to the hospital with LLM involvement.

1. This actually isn't new or AI-specific.
2. And no AI does not causes psychosis.

And most importantly, 95% of what you're reading on X about "schizophrenia" is medically inaccurate. 🧵

https://twitter.com/Noahpinion/status/1945933856764490201

It's shocking that this needs to be said, but please be kind to people.

Ketamine doesn’t work the way you think.

It’s not about the ego death.
Not the hallucinations.
Not the high.

The real reason it works—and why it works so fast—has nothing to do with the trip.

It’s something deeper.
And its changing computational psychiatry. 🧵 2/ Most antidepressants are like slow software updates.

Ketamine?

It’s a fast reset... rebooting the brain’s control circuits in hours, not weeks.

A full circuit rewrite that results in transformation.