Why Betrayal Trauma Hijacks Your Brain: How the Amygdala, Hippocampus, and Corpus Callosum Are Involved
By Tesa Saulmon, LMHC CSAT | Root to Bloom Therapy
“I don’t even recognize myself anymore.”
If you’ve experienced betrayal—whether it was infidelity, porn addiction, emotional affairs, or hidden secrets—you’ve probably thought something like this.
Maybe you’re having intense reactions that you know don’t match the moment:
Your partner sets down their phone, and your stomach drops.
You try to have a normal conversation, but suddenly you’re shaking or shut down.
You feel stuck in replay mode, reliving the discovery over and over, no matter how much time has passed.
It can feel like you’re losing your mind. But here’s the truth:
You’re not crazy. You’re traumatized. And trauma rewires your brain.
Let’s talk about why betrayal feels so big, so overwhelming, and so hard to “just get over.” It comes down to how three parts of your brain respond when your sense of safety and trust gets shattered:
Amygdala: Your built-in alarm system
Hippocampus: Your brain’s memory file cabinet
Corpus Callosum: The bridge between your emotional and logical sides
The Amygdala: Your Brain’s Fire Alarm
The amygdala is like your brain’s smoke detector. Its job is to keep you safe, scanning 24/7 for anything that feels like danger.
When betrayal happens, your amygdala gets stuck on high alert. It starts flagging everything that feels even close to the original hurt. That’s why:
A text notification can feel like a gut punch
A partner closing their laptop can trigger panic
Your body reacts before your brain can even explain why
The amygdala isn’t interested in logic. It doesn’t care about timelines. Its job is to scream: “Watch out! Don’t get hurt again!”
This is why you can know, rationally, that you’re “safe,” but your body still acts like betrayal is happening all over again.
The Hippocampus: Your Brain’s Memory Keeper (That Gets Overwhelmed)
The hippocampus helps organize your memories, so you can understand:
What happened
When it happened
Whether or not it’s over
But betrayal trauma floods the system. The hippocampus can’t file the event away properly, so your brain ends up:
Replaying painful moments like they’re happening right now
Getting triggered by smells, sights, or sounds that have nothing to do with your partner but feel connected somehow
Struggling to make sense of timelines or details because the memory feels jumbled
This is why you might question your own mind, saying things like:
“Am I remembering this right?”
“I know logically it’s over, but it still feels like it’s happening.”
That’s not because you’re broken—it’s because your hippocampus is overloaded.
The Corpus Callosum: The Bridge That Stops Working During Trauma
The corpus callosum is like a bridge connecting the two sides of your brain:
The left side is your logic, facts, language, and time awareness
The right side is your emotions, sensations, intuition, and trauma storage
When you’re in betrayal trauma, this bridge gets glitchy. It’s harder for your logical side to talk to your emotional side. You might think:
“I know they’re being honest now…”
“…but I still feel like I’m waiting for the next shoe to drop.”
This isn’t because you’re dramatic or unforgiving. It’s because your brain literally can’t connect the dots right now.
The right side of your brain is screaming, “Danger! This feels familiar!”
The left side is whispering, “But nothing bad is happening right this second.”
And the two sides? They’re struggling to communicate.
So What Does This Mean for Healing?
Once you understand what’s happening in your brain, you can stop blaming yourself for your reactions. This is biology, not character flaws.
Here’s what betrayal trauma does to your brain:
Brain Part and what it does in trauma:
Amygdala: Sounds the alarm, even when there’s no current danger
Hippocampus: Can’t organize or file the memory properly
Corpus Callosum: Struggles to connect logic and emotion
The Good News: Your Brain Can Heal
Your brain is built for healing and rewiring, but it takes time and intentional support.
Here’s what helps:
Therapy with someone who understands betrayal trauma
EMDR, somatic work, or trauma processing to help your body release what’s stuck
Safety and transparency from the betraying partner to help calm the alarm system
Empathy and co-regulation, so your nervous system can start to believe: “Maybe I’m safe now.”
You’re Not Overreacting—You’re Overwhelmed
If you’ve been betrayed and you feel like your body has a mind of its own, that’s because it sort of does.
Your brain is doing its best to protect you. It just needs help learning when it’s safe to let go.
At Root to Bloom Therapy, we specialize in helping betrayed partners, partners who have betrayed and want to change, and couples working toward healing. You don’t have to do this alone.
Call or Text: (850) 530-7236
Email: hello@roottobloomtherapy.com
Instagram: @talkingwithtesa
