Understanding Stress: What's Really Happening in Your Nervous System

Understanding Stress: What's Really Happening in Your Nervous System

You know that feeling when your heart races before a presentation? Or when you lie awake at 3am, mind spinning with worries? That's your nervous system doing exactly what it's designed to do—protect you. But here's the problem: it can't tell the difference between a genuine threat and your overflowing inbox.

After three decades working in healthcare, as a paramedic, nursing, clinical hypnotherapist, and corporate manager, specialising in stress relief and anxiety relief, I've seen firsthand how misunderstood stress really is. Most people think stress is just "feeling overwhelmed" or something you need to push through with willpower. But stress is actually a sophisticated neurobiological response that's been keeping humans alive for millennia.

The trouble is that our ancient survival system hasn't caught up with modern life.

Your Nervous System Wasn't Designed for 2026

Let's start with the basics. Your autonomic nervous system (ANS) is the part of your nervous system that runs automatically - you don't have to think about it. It controls your heart rate, breathing, digestion, and thousands of other processes. And it's always scanning for safety or danger.

This is where polyvagal theory comes in. Developed by Dr. Stephen Porges, polyvagal theory explains how our nervous system has three distinct states that evolved to help us survive:

The Social Engagement System (Ventral Vagal)This is your "safe and social" state. When your nervous system feels safe, you can connect with others, think clearly, be creative, and digest your food properly. Your face is animated, your voice has natural prosody, and you feel genuinely present. This is the state where you thrive.

The Mobilisation System (Sympathetic)This is your "fight or flight" response. When your nervous system detects a threat, it mobilises energy. Your heart rate increases, your breathing becomes shallow and rapid, blood rushes to your large muscle groups, and your digestive system shuts down. You're ready to fight or run. This response saved your ancestors from predators.

The Shutdown System (Dorsal Vagal)This is your "freeze or collapse" response. When your nervous system determines that neither fight nor flight will work, it shuts down. You might feel numb, disconnected, foggy, or extremely fatigued. This is an ancient survival mechanism—think of animals playing dead.

In my hypnotherapy sessions, I use a simple traffic light system to help clients understand these states: GREEN for safe and social, YELLOW for activated fight/flight, and RED for shutdown. It's a straightforward way to track what's happening in your nervous system.

The Problem with Modern Stress

Here's where things get complicated. Your nervous system is brilliant at detecting physical threats. If a car runs a red light while you're crossing the street, that fight/flight response kicks in instantly, pushing you out of the way. Perfect.

But your nervous system can't distinguish between a genuine physical threat and a psychological one. An aggressive email from your boss triggers the same physiological response as that car running the red light. Your upcoming mortgage payment activates the same system as a predator would have for your ancestors.

This is acute stress, and in small doses, it's not necessarily bad. It helped you meet that deadline. It gave you the energy to deal with the crisis. The problem comes when acute stress becomes chronic stress.

When Your Nervous System Gets Stuck: Understanding Chronic Stress

Chronic stress happens when your nervous system stays in a state of activation—constantly scanning for threats, never quite feeling safe enough to relax. It's like having a car alarm that won't turn off.

This is where many people in Brisbane and across Australia find themselves seeking stress relief and anxiety treatment. The accumulation happens for several reasons:

The accumulation of daily stressors. Each small stress such as traffic, notifications, deadlines, difficult conversations, it all adds up. Your nervous system never gets a chance to fully return to that green, safe state before the next stressor hits.

Unprocessed past experiences. Sometimes our nervous system learned early in life that the world isn't safe. Those early experiences create patterns that persist, even when the original threat is long gone. Your nervous system developed a template that says "stay alert," and it's still running that program.

The loss of safety cues. Modern life has stripped away many of the things that naturally regulate our nervous system namely connection with nature, genuine social bonding, physical movement, predictable rhythms. Instead, we're overstimulated, isolated, and constantly "on."

What most people don't realise is that you can be in a chronic stress state even when you don't "feel stressed." You might just feel tired, foggy, or numb. That's often your nervous system in shutdown mode - the red state - which is still a stress response, just a different kind.

Why Your Body Can't Tell Fiction from Reality

This is one of the most important things to understand about stress: your nervous system responds to perceived threats, not just actual ones.

When you lie in bed worrying about tomorrow's presentation, your body releases the same stress hormones (cortisol and adrenaline) as it would if you were being chased. Your amygdala, the brain's threat detection centre, doesn't care that the presentation is hours away or that it's probably going to be fine. It just detects "threat" and initiates the stress response.

This is why rumination and anxiety are so physically exhausting. You're not just thinking stressful thoughts and you're putting your body through repeated stress responses. Your heart rate increases, your blood pressure rises, your muscles tense, your digestion slows down. Over and over, all day long.

And here's the really tricky part: once your nervous system is in a heightened state, it becomes more sensitive to threats. It's called neuroception, the unconscious detection of safety or danger. When you're already running in yellow (fight/flight) or red (shutdown), even small things trigger bigger reactions. The comment that wouldn't have bothered you last week now feels like a major threat. Your threat threshold has lowered.

The Window of Tolerance: Your Capacity for Stress

Psychiatrist Dan Siegel describes something called the "window of tolerance"—the zone where you can function effectively, process information, and respond flexibly to life's challenges. When you're in your window of tolerance, you're in that green state. You can handle stress without becoming overwhelmed.

But chronic stress narrows your window. You become either hyper-aroused (too much yellow: anxious, reactive, unable to settle) or hypo-aroused (too much red: shut down, disconnected, exhausted). You ping-pong between the two, rarely feeling genuinely calm and present.

The good news? Your window of tolerance isn't fixed. You can widen it through nervous system regulation and evidence-based stress management techniques. That's exactly what clinical hypnotherapy and polyvagal-informed approaches are designed to do.

What Actually Happens in Your Body During Stress

Let's get specific about the physical cascade that happens during a stress response:

Within milliseconds of detecting a threat, your hypothalamus (a small region at the base of your brain) activates your sympathetic nervous system. Your adrenal glands release adrenaline. Immediately:

• Your heart rate and blood pressure increase

• Your breathing becomes rapid and shallow

• Your pupils dilate

• Blood flow is redirected from your digestive system to your large muscle groups

• Glucose is released into your bloodstream for quick energy

• Your muscles tense, ready for action

• Non-essential systems (like digestion and reproduction) shut down

If the stress continues, your hypothalamus triggers the release of cortisol, the primary stress hormone. Cortisol keeps your body on high alert. It's supposed to be released in short bursts and then return to baseline. But with chronic stress, cortisol levels stay elevated.

This is where the real damage begins. Chronically elevated cortisol affects nearly every system in your body, immune function, digestion, sleep, cognition, and even genetic expression.

The Stress-Sleep-Stress Cycle

One of the most damaging effects of chronic stress is on sleep, and sleep problems are one of the most common reasons people seek stress relief and anxiety treatment. When you're stressed, your body is literally designed to stay alert. Cortisol should be lowest at night and highest in the morning. But chronic stress flattens this curve. Your cortisol stays elevated when it should drop, making it hard to fall asleep or stay asleep.

Then, because you're not sleeping properly, your stress response becomes even more reactive the next day. Sleep deprivation impairs the prefrontal cortex: the part of your brain responsible for emotional regulation and rational thinking. At the same time, it amplifies the amygdala's threat response.

You become more emotionally reactive, less able to cope with challenges, and more likely to perceive neutral situations as threatening. Which creates more stress. Which disrupts sleep further. It's a vicious cycle.

The Good News: Your Nervous System Can Learn Safety Again

Here's what I want you to understand: none of this is a personal failing. You're not weak because you're stressed. You're not broken because your nervous system is stuck in a defensive state. Your nervous system is doing exactly what it's designed to do based on the signals it's receiving.

The challenge is that we can't think our way out of nervous system dysregulation. You can't just "think positive" or "try to relax" when your body is in a genuine threat state. That's like telling someone who's drowning to just try swimming better.

Instead, we need bottom-up approaches—techniques that work directly with the body and nervous system to signal safety. This is where clinical hypnotherapy for stress relief becomes incredibly powerful, and why more people are turning to hypnotherapy in Brisbane and throughout Australia for effective anxiety relief.

Hypnotherapy works by accessing the subconscious mind—the part that's actually running your autonomic nervous system. In a hypnotic state, we can help your nervous system learn new patterns, process what's keeping it stuck in a defensive state, and literally retrain your stress response.

Unlike talk therapy alone, which primarily engages the conscious, thinking brain, clinical hypnotherapy for stress and anxiety works at the level where the stress response actually lives—below conscious awareness, in the body and the autonomic nervous system.

Moving Forward: Evidence-Based Stress Management

Understanding what's happening in your nervous system is the first step toward regulating it. When you can recognise that your racing heart, shallow breathing, or overwhelming fatigue are nervous system responses rather than character flaws, you can start working with your body instead of against it.

In the coming articles in this series, we'll explore the hidden causes of chronic stress, the specific ways stress affects your body and brain, and most importantly—evidence-based techniques for stress relief and anxiety management, including how clinical hypnotherapy can help regulate your nervous system and build genuine resilience.

Because effective stress management isn't about pushing through or being tougher. It's about teaching your nervous system that it's safe to relax again.

About Rebalance Hypnotherapy Brisbane

Looking for effective stress relief and anxiety treatment in Brisbane? At Rebalance Hypnotherapy, I specialise in evidence-based clinical hypnotherapy for stress management, anxiety relief, and nervous system regulation. With over 30 years of healthcare experience and advanced training in polyvagal theory and trauma-informed approaches, I help clients throughout Brisbane and Australia move from chronic stress and dysregulation to genuine calm and resilience.

Whether you're dealing with workplace stress, anxiety, sleep problems, or feeling constantly overwhelmed, clinical hypnotherapy addresses these issues at their source, in your nervous system, not just at the level of thoughts and behaviours.

Ready for Real Stress Relief?

I offer both face-to-face hypnotherapy sessions in Brisbane and telehealth appointments throughout Australia. If you're tired of managing stress with willpower alone and ready to address it at the nervous system level, book a free consultation to discuss how clinical hypnotherapy can help you regulate your stress response and reclaim your sense of calm.

📍 Servicing Brisbane and surrounding areas💻 Telehealth available Australia-wide📞 Contact Rebalance Hypnotherapy today for your free consultation

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Related Articles:

• Coming soon: The Hidden Causes of Chronic Stress

• Coming soon: How Chronic Stress Affects Your Body

• Coming soon: Evidence-Based Stress Management Techniques