top of page

The Biological Similarities and Differences of Anxiety, Stress, and Chronic Stress

When you hear someone talk about feeling stressed or anxious or maybe even worried, do you assume they mean the same thing? Or are they all different things entirely? Are they experienced in different ways? Are they caused by different circumstances? Do they create different symptoms?

I've written previously about the difference between anxiety and worry. You can take a look here. So, I won't cover that again in this article. But it might be worth just briefly recapping. About worry and what it is and what it isn't.

Worry is a behaviour. It is a thought habit that we create. It causes unpleasant emotions. Usually anxiety, but sometimes frustration. And it tends to be hard to stop once we start doing it.

Anxiety, in contrast, is an emotion. It is normal to experience anxiety.

As humans, our primary goal is survival. You may have heard of survival of the fittest coined by Darwin. Anxiety is experienced when our survival is threatened in any way.

If we think there is a chance we may be hurt. Our food may be reduced. Our community is put at risk. Our home was lost. Or our intimate relationships are damaged in any way. Then we can experience anxiety and we respond with one of the 5Fs.

The 5FS are fight, flight, friend, freeze and faint.

Our minds are receiving information all the time. From inside our body through our nervous system. And from our external environment via our senses.

Our mind then makes sense of what we touch, taste, see, hear, or smell.

We have two systems in the brain. A fast-track, System 1, which deals with risks to our survival.

And the slower, System 2, which goes via the pre-frontal cortex (the thinking part of the brain).

The Reticular Activating System (RAS) of the brain filters what is to be attended to. However, in people who suffer Chronic Stress (long-term illness, unemployment, single-parent, etc.), they are hypervigilant and more likely to be activated (get stressed) by more things at a lower level as the Thalamus has been eroded (Yoshi et al, 2017). This explains why people who live with longer term stress find it more difficult to switch off and relax.

Whether the signal comes via the RAS or the Thalamus, if it is perceived as a threat to our safety, or survival, it is fast tracked through System 1 via the Sympathetic Nervous System and the Hypothalamus-Pituitary-Adrenal (HPA) Axis.

It is at this point that we first recognise anxiety in our mind as a thought in terms of a threat.

And we automatically act to remove ourselves from that threat.

Friend – we may try to talk our way out of it.

Flight – we try to run away, literally, or metaphorically.

Fight – we might become physically or verbally aggressive.

Faint – if there is blood loss, we may lose consciousness.

Freeze – if we see no escape, we may play dead or dissociate.

None of these are chosen consciously. They are selected purely for survival.

At the same time as this is happening in the mind, the body is also experiencing an automatic process.

Glucocorticoids and catecholamines are released into the blood supply. These chemicals activate numerous biological mechanisms to enable the individual to cope with the perceived stressor.

If the incoming message received from the body, or outside via the senses, is not deemed to be a risk, then System 2 is activated, and the emotion created will be one other than anxiety. The mind will remain curious, and the body will not prepare for one of the 5Fs.

Unfortunately, this system does sometimes malfunction.

Sometimes the RAS becomes over-sensitive to a particular trigger, and someone may start to feel intense anxiety even when there is not a severe threat. This can be seen in cases of Panic Attack for instance.

Stress is described as ‘emotional or physical tension’ and this may occur without activating System 1.

However, Chronic Stress is ‘a consistent sense of feeling pressured and overwhelmed over a long period of time’

Chronic Stress can lead to anxiety, activating System 1, as the mind interprets it as a threat to survival and reactivating the 5Fs continuously until the threat has been neutralised or avoided.

Thus, you can see why someone with Chronic Stress (a lone-parent, someone without employment, someone who has a physical difficulty or long-term condition, for example) may feel so fatigued, unable to concentrate, experience physical ailments and pain, and develop Stress Illness and other long-term illnesses.

If you experience Anxiety, Stress, Chronic Stress, or Stress Illness one of the first things to do is to learn how to settle your body and bring it back to a rest state. I’ve created a FREE Calming Techniques Guide which you can download here



bottom of page