The Thought Biopsy

Three Essential Tools Every Self-Brain Surgeon Needs, Part 1

[If you missed last week’s letter, be sure to read it, as it will help you get the most out this three-part series. Click here to read!]

This might surprise you: Not every thought you have is true.

Just like not every white spot I see on a brain MRI is dangerous, not every thought that pops into your mind is worth believing.

In neurosurgery, one of the first procedures we teach is the brain biopsy. When we see something suspicious on a scan, we don’t rush into major surgery. First, we use a needle to sample the tissue, to find out what it is—before we act.

Why? Because going in blind causes unnecessary harm.

We teach biopsies early because they’re simple, safe, and foundational. They give young neurosurgeons confidence—and a way to avoid dangerous mistakes.

The same principle applies to your thoughts.

You have thousands of automatic thoughts every day. Most of them aren’t real thoughts from your mind—they’re just pre-programmed brain scripts trying to save energy. They’re fast, familiar, and loud—and they sound like your own voice.

But here’s the truth:

Reacting to automatic thoughts without examining them is like a surgeon operating without a biopsy. It leads to damage, pain, and unresolved problems.

This is why the first three Commandments of Self-Brain Surgery™ exist:

1. Don’t commit self-malpractice

2. Feelings are not facts

3. Thoughts are not always true

(You can click here for a podcast episode about the first five commandments, and click here for an episode about the second five)

Before you react, you need to pause and ask:
Is this thought real? Is it true, helpful, and necessary?

That’s the Thought Biopsy. It’s a simple, life-changing mental habit that puts you back in charge of your brain.

“We take every thought captive…” — II Corinthians 10:5

Dr. Warren and PA Damon performing neurosurgery. 2024. Photo credit: Kristin Genatone

Remember: you are NOT just your brain (click that to learn more).

Brain and mind are distinct, and the successful self-brain surgeon understands that mind is in charge of brain. But there’s a problem: Most people are unaware that these automatic thoughts are brain programs. We hear them in our own voice, and we believe that they are real thoughts that reflect true things.

🎯 Want to start using the Thought Biopsy in your own life?

👉 Subscribe to my newsletter, and I’ll send you my free Thought Biopsy Worksheet to help you start.

Already subscribed? Just email us at contact@drleewarren.com and we’ll send it your way.

🎧 And tune in to Mind-Change Monday tomorrow on the podcast—where we’ll walk through the Thought Biopsy together. (Paid Subscribers can scroll to the bottom of this post for early access!)

You're already performing self-brain surgery. Every thought, every reaction, every moment.
The key is to do it well.
And the first step?
Learn to biopsy your thoughts, because you can’t change your life until you change your mind.

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📣Announcing: The Brain Surgeon and the Therapist 📣

On July 11, I’m recording the first in a series (hopefully) of podcasts with Gina Birkemeier, a brilliant therapist and author. Gina was on my podcast before, and we realized that it would be helpful to you to have us get together again and answer some of your questions. (🎩 Hat tip to Gina for the catchy title)

This is your chance to ask questions of Gina, me, or both of us, and we’ll build an episode (or possibly more if you like it). Here are three ways you can submit questions:

1. The most fun would be for YOU to join us on the podcast! You can record a video question using this link, and we’ll include you in the show! It’s super easy, and all you have to do is record. We’ll take care of the rest. Please start with your name and where you’re from, and then ask your question.

2. You can leave your question via voice mail, and we’ll use your voice on the show. SpeakPipe has a limit of 90 seconds for the messages.

3. You can email your questions to contact@drleewarren.com

Please remember: we cannot answer specific medical questions, and we cannot provide medical care or mental health care to you. Answering a question does not constitute a doctor-patient or therapist-patient relationship. If you want your question answered without using your name or voice, please email it to us instead.

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👉Share this message with someone who needs to learn the life-changing power of self-brain surgery. If you share with three friends who subscribe, I’ll give you a month of access to my paid content for free!

Want more tools for rewiring your brain and renewing your mind?

🎙️ Subscribe to The Self-Brain Surgery with Dr. Lee Warren Podcast for weekly strategies to change your brain—and your life.
📖 Grab my book Hope Is the First Dose for a roadmap to recovery and transformation.
📘 And stay tuned for The Life-Changing Art of Self-Brain Surgery—coming February 2026!

The good news is, you can start today.

Let’s get after it. 🧠✝️

Lisa and I are praying for you.

Dum spiro spero (While I breathe, I hope),

Lee

Psalm 71:14 ("As for me, I will always have hope.")

From the banks of the North Platte river on Moon River Ranch in Nebraska, USA

Be sure to check out the archive of previous posts if you missed last week’s letter.