What Is Anxiety - and Why Does It Happen?

Oct 8

7 min read

Understanding what your nervous system is actually trying to do

Anxiety can be incredibly confusing.

You can be sitting at your desk, walking through the supermarket, driving your car or having dinner with friends when suddenly your heart starts beating faster. Your chest tightens. Your breathing changes. Your stomach turns. Your thoughts accelerate and something inside you says, I need to get out of here.

And sometimes there is no obvious reason for it. This is one of the things I hear frequently in my work: “But nothing was actually wrong.”

Consciously, perhaps not. But your nervous system does not only respond to what is happening around you. It also responds to what it has learned, what it remembers, what it anticipates and what it believes may be about to happen.

Anxiety is a protective response

Anxiety is part of the body's protective system.

When the brain and nervous system detect potential threat, a series of physiological changes can occur. The sympathetic nervous system becomes more active. Stress hormones such as adrenaline and cortisol may increase. Heart rate and breathing can accelerate. Muscles prepare for action. Attention narrows towards whatever might be important for survival.

These responses are enormously useful when there is genuine danger. If a car suddenly pulls out in front of you, you do not want to spend several minutes consciously analysing the situation. Your nervous system needs to mobilise you immediately. The difficulty is that the human nervous system does not respond only to immediate physical danger.

It can respond to predicted danger too.

And what constitutes “danger” is influenced by far more than what is happening in this particular moment.

Your nervous system is constantly making predictions

The brain is continually processing information from both outside and inside the body. It is taking in facial expressions, voices, movement, physical sensations, memories, previous experiences and the environment around you. At the same time, it is monitoring what is happening internally: your heart rate, breathing, temperature, tension, hunger, fatigue and countless other physiological signals.

Much of this happens outside conscious awareness. Your nervous system is essentially asking:

What is happening?
What might happen next?
And do I have enough capacity to deal with it?

This is one reason anxiety can appear when objectively nothing dangerous is happening. A racing heart might be interpreted as threat. An unfamiliar environment might create uncertainty. Conflict may activate an old expectation of rejection.

Even being at home may activate an expectation of being ridiculed, spoken to rudely, criticised or told that you are wrong, particularly if your nervous system has learned to anticipate those responses in that environment.

Nothing needs to be happening in that exact moment for the body to begin preparing for what it has learned might happen next.

Being watched might trigger a learned fear of judgement.

Exhaustion may simply leave the nervous system with less capacity to manage normal demands.

The conscious mind may be saying, “I'm standing in a supermarket buying avocados. Meanwhile, the nervous system may be responding as though something important is at stake. Both experiences can exist at the same time.

Why anxiety can feel as though it comes from nowhere

Sometimes anxiety has an obvious trigger. Sometimes it doesn't. This does not necessarily mean there was no trigger. It may simply mean that the trigger occurred below conscious awareness.

The brain can begin responding to threat-related information extremely quickly, while interoception — our perception of sensations arising from inside the body — also contributes to how we experience anxiety.

You might notice your heart beating harder and become frightened by the sensation. That fear creates further activation. Your heart beats faster. You notice it more. Your mind begins searching for an explanation.

What's happening?
Why do I feel like this?
Am I going to panic?
What if I can't stop it?

The body's protective response can then become the thing we are frightened of. This can create an exhausting loop:

sensation → fear of the sensation → more activation → stronger sensation → more fear.

But there is another layer that I think is important. Sometimes anxiety is not simply about what is happening in the body today. It can also reflect what the nervous system has learned over time.

Anxiety makes more sense when we look at the foundations underneath it

In my work at Project Pure, I use six Foundations of Regulation: Safety, Attachment, Authenticity, Connection, Agency and Rhythm.

Rather than viewing anxiety only as a collection of symptoms that need to disappear, we can become curious about the foundations underneath those symptoms.

Safety

Does my nervous system experience the world — and my own body — as sufficiently safe?

Safety is not simply knowing intellectually that nothing bad is happening. We can know we are safe while our physiology is still preparing for danger.

This is why telling someone with anxiety to “just relax” rarely changes much.

The body needs its own evidence.

Attachment

Humans are relational mammals. Our nervous systems developed in relationship with other people.

Being seen, soothed, responded to and supported helps teach the developing nervous system what to expect from relationships and from the world around us.

Experiences of inconsistency, rejection, loss or relational uncertainty can therefore become highly relevant to anxiety, even many years later.

Authenticity

What happens when being yourself feels risky?

Perhaps you learned to stay quiet, keep everybody happy, hide emotion, achieve, perform or become the version of yourself that received approval.

Constantly monitoring how we are being perceived requires enormous nervous-system energy.

Sometimes anxiety is connected not only to fear of what might happen, but to the exhausting work of trying to remain acceptable.

Connection

Humans regulate through connection.

Isolation, loneliness and disconnection can all influence how safe the nervous system perceives our environment to be. Equally, the presence of someone we trust can change our physiology remarkably quickly.

Regulation is not always something we are supposed to achieve alone.

Agency

Anxiety often contains a powerful sense of “I can't.”

I can't cope.

I can't leave.

I can't say no.

I can't handle this feeling.

I can't control what happens next.

Agency is our felt sense that we have choices and can act on our own behalf. Sometimes one of the most important changes in anxiety is not making the anxious sensation disappear, but helping the nervous system discover:

I have options. I can respond. I can look after myself.

Rhythm

The nervous system also lives within biological rhythms.

Sleep and wake cycles, movement, daylight, food, rest, activity and predictable routines all provide information to the body.

When these rhythms are repeatedly disrupted — through chronic stress, poor sleep, overwork, illness, shift work or simply living at a pace that continually exceeds our capacity — the nervous system can become increasingly reactive.

Sometimes anxiety needs psychological exploration.

Sometimes the system is also simply exhausted.

Usually, human beings are more complex than one explanation.

So what do you do when anxiety suddenly appears?

Imagine you are standing in a supermarket and anxiety suddenly rises. Your heart accelerates. Your chest tightens. You feel slightly dizzy. Your first instinct may be:

Get out.

And sometimes leaving is exactly what you need to do. Agency matters. But if you are physically safe and have enough capacity to remain where you are, you might first give your nervous system some new information.

Feel your feet making contact with the floor.

Look around the room rather than disappearing entirely into the sensations inside your body.

Notice three ordinary things around you.

A shelf.

Someone pushing a trolley.

The sound of people talking.

Allow your breathing to move through your nose without trying desperately to make yourself calm.

And remind yourself where you actually are:

I am here.

This is anxiety.

My nervous system is trying to protect me.

I do not have to solve everything in this moment.

I am OK.

The purpose is not to battle the anxiety. It is to help the nervous system distinguish between activation and actual danger. Because when we repeatedly experience anxiety and immediately escape from the situation, the nervous system can sometimes learn:

Something dangerous happened → I escaped → escaping kept me safe.

Avoidance can therefore bring enormous short-term relief while strengthening anxiety over time. This is also why overcoming anxiety is rarely about finding the perfect technique to make uncomfortable sensations disappear. It is about gradually developing the capacity to experience activation without automatically interpreting that activation as evidence that something terrible is happening.

Perhaps anxiety isn't the enemy

Anxiety is uncomfortable. At its most intense, it can be frightening and profoundly disruptive. But the response itself exists for a reason.

Your nervous system is trying to anticipate danger, mobilise resources and protect you. Sometimes it simply becomes too good at its job. So rather than beginning with:

“How do I get rid of my anxiety?”

we can become interested in a different set of questions.

What is my nervous system responding to?
What has it learned to expect?
Where do I feel I have no choice?
What happens when I am fully myself?
Where do I experience connection?
What does safety actually feel like in my body?
And what might my nervous system need in order to update what it currently believes?

Anxiety begins to look different when we stop seeing it only as something malfunctioning inside us and begin understanding it as information.

The goal is not necessarily to build a life in which the nervous system never activates.

A healthy nervous system should activate.

It should mobilise us when something matters, protect us when danger is present and give us energy when action is required.

The work is helping it become increasingly able to recognise the difference between what was dangerous, what might be dangerous, and what is actually happening now.

And that is where regulation begins.

Anxiety Therapy and Nervous System Regulation in Christchurch

I work with anxiety and insomnia through Deep Release Therapy (DRT) at Project Pure – Anxiety + Insomnia Clinic in Sumner, Christchurch.

DRT combines nervous system regulation, psycho-somatic therapy and deeper inquiry. The work looks beyond anxiety as an isolated symptom and considers the broader patterns and experiences that may be influencing the nervous system, while developing greater capacity for regulation in everyday life.

If you are experiencing anxiety, overthinking, physical tension, hyper-vigilance or difficulty sleeping and would like to understand what may be happening beneath the symptoms, you can contact Project Pure to arrange a free 30-minute consultation.

Annelies Basten, MPsych

Nervous System & Psycho-Somatic Therapy

Project Pure – Anxiety + Insomnia Clinic

Sumner, Christchurch, New Zealand

References

Khalsa, S. S., et al. (2018). Interoception and Mental Health: A Roadmap. Biological Psychiatry: Cognitive Neuroscience and Neuroimaging, 3(6), 501–513. PubMed

Paulus, M. P., & Stein, M. B. (2006). An Insular View of Anxiety. Biological Psychiatry, 60(4), 383–387. PubMed

Krypotos, A-M., Effting, M., Kindt, M., & Beckers, T. (2015). Avoidance learning: a review of theoretical models and recent developments. Frontiers in Behavioral Neuroscience, 9, 189. PubMed Central (PMC)

Hofmann, S. G., & Hay, A. C. (2018). Rethinking Avoidance: Toward a Balanced Approach to Avoidance in Treating Anxiety Disorders. Journal of Anxiety Disorders, 55, 14–21. PubMed Central (PMC)

Coan, J. A., & Sbarra, D. A. (2015). Social Baseline Theory: The Social Regulation of Risk and Effort. Current Opinion in Psychology, 1, 87–91. PubMed Central (PMC)

Bornstein, M. H., & Esposito, G. (2023). Coregulation: A Multilevel Approach via Biology and Behavior. Children, 10(8), 1323.