The Significance of the Autonomic Nervous System

by | Aug 19, 2021 | Resources

We live in world where practically all of us have experienced some level of stress, at some point during our lives. Some of us push on through life whenever it appears, and sometimes our stress disappears of its own accord, without a lingering trace. However, there are a large number of us who experience significant levels of stress – and one of its byproducts, anxiety – more often often and more deeply than others.

Because stress and anxiety are so common among the people around us, we may be led to believe that these pressures are normal and that this is how things should be. On the other hand, we have people who claim that stress is bad for our health, and that we should strive to eliminate it entirely from our lives.

So, what’s the real story, when it comes to stress? Well, the situation is a bit more complex than simply calling stress good or bad.

For example: stress responses prepare our body for action or inaction to face an upcoming threat. You might have heard about the ‘fight, flight or faint’ response before. It helped our ancestors to survive in wilderness, whenever – for example – they encountered some dangerous animal in the wild. They had to either fight it, run from it or simply “play dead” until the danger was gone, and during those moments, their bodies reacted accordingly. Even though these days are generally far behind us, and our environment has changed unrecognisably since, the mechanism in our body has not.

Today, we call this mechanism the Sympathetic Nervous System. It’s activated as a stress response, and constitutes a crucial part of the Autonomic Nervous System. The Autonomic Nervous System also incorporates the Parasympathetic Nervous System, which is activated during safe and calm times. It essentially switches our body to our resting and digesting mode.

Let me show you what I mean by this. Below, you’ll find some examples of what happens in our body when either system is activated:

Sympathetic Nervous System

– Eye –

Pupils dilate

– Lungs –

Breathing rate increases

– Heart –

Heart beat speeds up
Blood vessels constrict

– Stomach –

Digestion inhibited
Adrenal glands release adrenaline and noradrenaline

– Bladder –

Bladder relaxes

Parasympathetic Nervous System

– Eye –

Pupils constrict

– Lungs –

Breathing rate decreases

– Heart –

Heart beat slows down
Blood vessels relax

– Stomach –

Digestion stimulated
Pancreas releases insulin and digestive enzymes
Blood vessels in gut are dilated

– Bladder –

Bladder contracts

Our Autonomic Nervous System is responsible for keeping a balance between Sympathetic and Parasympathetic Nervous Systems – it switches between them when needed. An example situation could look like this:

A person is walking calmly in the park; the Parasympathetic Nervous System is active.

There is a sudden movement and noise in the bushes next to the person; the Sympathetic Nervous System is activated because something potentially dangerous has just happened.

The person’s body is now ready to fight, fly or faint.

After a couple of seconds, it turns out that source of the noise and movement in the bushes was just a squirrel.

The danger (or rather, the perception of danger) is gone. The Parasympathetic Nervous System turns back on.

The person relaxes again and continues with their walk.

The mechanism is as simple as that. Our body switches between systems automatically, and we don’t have to consciously do anything to make it happen.

So, what does all this have to do with stress?

Our fight, flight, faint response is also activated when we perceive a danger that is not physical and does not require us to physically react. Let’s look at a situation that can occur at work:

We can see that our boss is wound up today. At some point he approaches us and says that he wants to see us. We know that he will not hurt us physically, yet if we perceive this situation as a danger, then our Symptomatic Nervous System kicks in with the same physical, bodily reactions as described above.

Nowadays, it is easy to feel overwhelmed by situations and information that can be perceived as a danger or a risk of danger, which in turn causes the automatic stress response in our body. What makes things worse is that we often can’t or don’t know how to fight or escape this stressful situation, and we stay in this stress response mode for longer than we should.

Our Sympathetic Nervous System developed to help us to deal with dangerous situations, and to turn itself off so that we can return to a more default, relaxed state. It should not stay on all the time, and we should not live in stress response mode for long. If we are in stress response mode for long enough, then it can affect us negatively both on physical and mental levels.

I hope that the above explanation has helped you to understand a little better about how our body works and how our thoughts can affect our body. If you believe that you suffer from stress or feel anxious, and could use some help in reducing level of stress or anxiety in your life, I’m here to help.