The Hidden Reason Pain Won’t Go Away: How the Autonomic Nervous System Fuels Chronic Symptoms (Learned Pain)

Think of your body as an orchestra.You can buy the finest violins, cellos, and trumpets (therapy, supplements, diets, exercise), but if the conductor is frantic, rushing the tempo, or skipping cues, the whole performance will sound off.

Your autonomic nervous system is that conductor. It controls:

• Muscle tone

• Breathing rhythms

• Heartbeat and circulation

• Digestion and motility

• Hormone release

• Pain perception

• and so much more!

  
  

In short: it’s the operating system of your body. And like any OS, when it gets bugged or overloaded, everything downstream glitches.

Afferent and Efferent Signals: The Feedback Loop That Shapes Reality

Your nervous system is constantly exchanging information:

• Afferent signals (Arrive): incoming messages from the body to the brain. These include interoception (gut stretch, heartbeat, breath, nausea, temperature) and exteroception (sights, sounds, touch, smells).

• Efferent signals (Exit): outgoing commands from the brain to the body. These include instructions to speed up your heart, tense your muscles, clamp your gut, or shift you into rest-and-digest.

  
  

Here’s the kicker: your brain doesn’t just passively read afferent data. It predicts what those signals mean based on past experiences. If your brain decides something feels unsafe—even if there’s no real danger—it sends efferent commands to protect you. Those commands change how your body feels, which then sends new afferent signals back, confirming the “danger” story.

This is the symptom loop:

1. Afferent signals arrive (gut tightness, noise, a look from someone).

2. The CNS predicts meaning: “safe or unsafe?”

3. Efferent commands exit (fight/flight, shutdown, or social engagement).

4. The body creates sensations (if figth or flight for example, = pain, nausea, tension).

5. Feedback reinforces the loop (“See? Danger!”).

   
   

Over time, this loop gets wired in, and symptoms persist even without a real threat.

Learned Pain: When Protection Becomes the Problem

Imagine you strained your back once. Your body braced up to protect the injury. That’s smart in the short term.

But months later, an email from your boss lands, and your brain—using its old “threat template”—decides to brace those same muscles again. Now your pain isn’t coming from tissue damage but from the nervous system predicting risk and overprotecting.

This is called central sensitization: real pain, learned by the system.

The cycle looks like this:

• Injury or trauma teaches the system to guard.

• Stressful cues trigger the same protective prediction later.

• The brain amplifies pain as an alarm signal.

• Movement feels risky, so you avoid it.

• Avoidance leads to deconditioning, which makes pain easier to trigger.

It’s not imaginary—it’s the nervous system doing its job too well.

How the Autonomic Balance Shapes Symptoms

Your autonomic nervous system works like a dimmer switch, shifting between three main states:

1. Sympathetic (fight/flight)

   • Purpose: mobilize now.

   • Signs: fast heart, shallow breath, muscle bracing, racing thoughts, gut urgency or constipation, insomnia.

2. Ventral vagal (social engagement)

   • Purpose: safe enough to rest, digest, connect.

   • Signs: steady heart, relaxed breath, clear thinking, easy digestion, curiosity, compassion.

3. Dorsal vagal (shutdown)

   • Purpose: conserve energy in overwhelm.

   • Signs: fatigue, brain fog, cold extremities, constipation, numbness, flat mood.

     
     

Healthy regulation means you can move between these states flexibly and return to ventral vagal safety often. But when your system gets stuck—say, in sympathetic fight/flight—automatic processes like digestion, pain perception, and sleep go haywire.

Everyday Loops That Wire Chronic Symptoms

The presentation gave so many relatable examples of how symptoms get wired. Here are a few:

• IBS Loop: After food poisoning, gut stretch gets tagged as “danger.” The brain clamps or speeds motility, tightening muscles, altering secretions → pain/urgency → body feeds back “See? Danger.” Even after the infection heals, the loop persists.

• Criticism/Shame Loop: A sharp tone recalls old criticism. Sympathetic output triggers flushing, tight throat, chest breathing → reflux, cramps, diarrhea. Avoidance reinforces “criticism = danger.”

• Overdoing Loop: If productivity was tied to safety or worth, rest feels unsafe. Evenings or calendar pings trigger fight/flight → heart races, gut clamps, muscles brace. Over time, chronic tension, insomnia, and gut symptoms develop. This is a very common one!

• Not Seen = Abandonment Loop: A partner glances at their phone mid-story. Old wiring says “I’m invisible.” The brain predicts connection threat → heart spikes, jaw clenches, gut cramps, racing thoughts. Protest behavior brings short-term relief, reinforcing the loop.

Each of these is an example of the nervous system protecting you—sometimes from events decades ago. Plus, this all happens subconsciously!

Why Patterns Stick: The GPS Analogy

Your nervous system learns by repetition. If a response kept you safe once, it gets stored as a go-to template.

It’s like a GPS that keeps rerouting you around a neighborhood where there used to be construction. Even when the road is clear, the GPS insists on the detour—until you update the map by repeatedly taking the new route.

The nervous system is the same: what fired together, wired together.

Allostatic Load: Why Your Backpack Feels Heavy

Another reason chronic symptoms persist is allostatic load—the cumulative wear and tear of stress. Imagine carrying a backpack. Each rock is a stressor: poor sleep, perfectionism, money worries, relationship tension, phone overload, medical uncertainty.

Your body adapts to carry the load: braced muscles, chest breathing, brittle sleep, gut dysmotility, amplified pain. Over time, those adaptations become your baseline.

This is why small triggers can cause big flares. Your system is already overloaded.

The Window of Tolerance: Why You Flare Easily

We all have a “window of tolerance,” the range where we can feel and think at the same time. Inside it, stress rises and falls like a manageable wave. Outside it, we tip into fight/flight or shutdown.

With chronic stress, the window narrows. A small email, a food, or a glance from someone can push you into dysregulation. This explains “mystery flares” that seem to come from nowhere.

Healing means gently widening your window again.

The Good News: Your Nervous System Can Relearn

Here’s the hopeful part: your nervous system is plastic—it can change. Just like it learned patterns of protection, it can learn safety again.

Retraining works by:

• Pairing old cues with new safety (ventral vagal/social signals).

• Adding small, repeated experiences of regulation.

• Lightening the load (reducing unnecessary stressors).

• Improving recovery (downshifts, rest, co-regulation).

Over time, the system updates its “map,” stops overprotecting, and symptoms lose their grip.

If I could heal, so can you.

I now offer 1:1 nervous system coaching here. I teach you what I did, step-by-step, to heal myself. You don't have to do it alone.

with love,

Cam