MARIN THERAPY PARTNERS | BLOG #2

What Happens in the Nervous System During Stress? (And Why It Can Feel So Overwhelming)

If you’ve ever wondered,
“Why does my body react so strongly—even when I know I’m safe?”
you’re not alone.

Stress is often talked about as something happening in the mind. But stress is not just a thought—it’s a full-body experience shaped by the nervous system.

Understanding what’s actually happening inside your body during stress can be profoundly relieving. It shifts the question from:
“What’s wrong with me?” to
“What is my nervous system trying to do for me?”

That shift matters—because your nervous system is not broken. It’s adaptive.

Your Nervous System Is Designed to Protect You

At its core, your nervous system is constantly scanning for one thing:
Am I safe, or am I in danger?

This process happens automatically and largely outside of conscious awareness.
When the nervous system senses safety, the body can:

• Relax
• Digest
• Connect with others
• Think clearly

But when it senses threat—even subtle or internal threat—it shifts into protection mode.

This is what we call the stress response.

The Stress Response: Fight, Flight, Freeze, and More

When your brain detects danger, it activates survival pathways almost instantly.
You may have heard of:

• Fight (anger, irritation, intensity)
• Flight (anxiety, restlessness, overthinking)
• Freeze (shutdown, numbness, disconnection)

There are also more nuanced responses like:

• Fawn (people-pleasing, prioritizing others to stay safe)

These are not personality traits.
They are biological responses designed to keep you alive.

What’s Actually Happening in the Body

When the stress response activates, several systems shift at once:

1. The Brain Prioritizes Survival

The more primitive parts of the brain become more active, while areas responsible for reasoning and planning become less dominant.

This is why, in moments of stress, it can feel hard to:

• Think clearly
• Make decisions
• Access perspective

2. The Body Mobilizes Energy

Your nervous system prepares you to act.

You might notice:

• Increased heart rate
• Faster breathing
• Muscle tension
• A surge of energy or urgency

This is your body getting ready to fight or run.

3. Stress Hormones Are Released

Hormones like cortisol and adrenaline flood the system.

In short bursts, this is helpful.
But when stress becomes chronic, the body can remain in a prolonged state of activation.

4. Non-Essential Systems Go Offline

Functions like digestion, immune response, and long-term restoration temporarily take a back seat.
This is why chronic stress can impact:

• Sleep
• Digestion
• Overall health

Why Stress Can Feel So Intense (Even When Nothing Is “Wrong”)

Here’s the part many people don’t realize:
Your nervous system does not distinguish well between:

• Actual present danger
• Past experiences that felt overwhelming
• Internal cues (like thoughts, sensations, or emotions)

If your system has learned—especially early in life—that certain experiences are unsafe, it may continue to respond as though those conditions are still present.

This is where stress and anxiety often overlap.

In fact, if you haven’t yet read it, this connects closely with

Can Trauma Cause Anxiety? Why You Might Feel Anxious Much of the Time

When the nervous system becomes sensitized, it can:

• React more quickly
• Stay activated longer
• Have difficulty returning to baseline