The vegetative nervous system: How our cells react to the environment

The cells in our bodies do unbelievable things. Every process, voluntary or involuntary, is monitored precisely by our nervous system, regulated, and adjusted to our environment. At the same time, the cells of the nervous system supply us with vital information on our surroundings and control our blood pressure, our hormones, and necessary bodily functions.

Our nervous system is a complicated network regulating many bodily processes, and allowing us to collect information from our environment. Every touch, every sensation of pain, every smell, and every one of our movements is perceived by our nervous system, and the information is transmitted to the command center (i.e. to the spinal cord and the brain). At the same time, every voluntary, i.e. conscious, movement is signaled to the muscles from our brain via the nervous system, thus allowing us to actively maneuver through the world.

There are, however, more important differences to bear in mind: While the somatic nervous system (the one described above) accompanies all conscious processes such as muscle movement, stimuli, pain, etc., there is another vital system less often mentioned.

The vegetative nervous system

The vegetative nervous system, also known as the autonomous nervous system, controls many of our most important bodily functions. These include respiration, digestion, metabolism, and blood pressure, among other things. At the same time, it also supplies all inner organs and glands and communicates information and changes between these and our brain.

The key difference to the somatic nervous system is that we have no conscious control over any of these regulations. We may have an influence, but control is without a conscious decision from us. If we, therefore, wake up, or get tired, or drool, or we begin to sweat, our vegetative nervous system is responsible for this without conscious action by us.

And how does that work?

As we already know, the cells in our bodies are interconnected in complex interactions. Every external or internal stimulus, whether it affects our bodies directly or indirectly, is analyzed and processed by our cells, and a conscious or unconscious decision is made by us. If we smell our favorite dish, our saliva glands are stimulated. When the temperatures rise in the summer, our bodies regulate our metabolism so we don’t overheat, and when we wake up in the morning, our blood pressure rises so we don’t stumble through the day half asleep.

Now, however, on to the details of the vegetative nervous system.

Together, our nervous centers in the brain and our hormones control the vegetative system. The neural pathways run from our brain and spinal cord to the organs and end in the muscle cells of the intestinal wall or the heart, for example. This way, organ functions are quickly adapted to any requirements. Hormones are transported via the blood, and therefore it takes longer for them to reach the target organ and for us to perceive their effects in our bodies (an example for this is tiredness setting in when it gets dark).

So far, so good.

The whole system gets a little more complex, however! In general, the vegetative nervous system is classified into two parts with different functions, acting in this manner as counterparts to each other.

The sympathetic nervous system

Sounds nice, doesn’t it? The sympathetic nervous system becomes active when we are in stressful situations or emergencies, or if such situations can become imminent. Ever heard of the “fight or flight” principle? The sympathetic nervous system is responsible for preparing the body for confrontation. This means that our pulse increases, the heart muscle contractions are more forceful, the respiratory pathways and pupils expand to aid in breathing and to make our eyes more perceptive. This part is also responsible for the release of stored energy and the force of our muscles increasing, our neck hairs standing on end and our hands sweating. In short: It ensures that we are ready for any extreme situations.

However, it’s not only there to activate our bodies, but also to suppress less important bodily functions in stressful situations. This means that processes like digestion or the urge to urinate are slowed down when our sympathetic nervous system is active.

The parasympathetic nervous system

The parasympathetic nervous system is far more relaxed in this regard. This is meant literally, as this part of the vegetative nervous system is in charge of ensuring all important bodily functions take place when we are in calm and relaxed situations. This entails reserves being refilled, regeneration, and activation of the digestive system. Blood pressure is lowered, tissue is rebuilt, the metabolism runs more efficiently and we are supplied with fresh energy.

Together, these two systems regulate our bodies and ensure that we get the most out of them, depending on our needs. By targeted activation and suppression of different parts of our bodies, these two coordinate perfectly and work together and “against each other” at the same time.

Vegetative nervous system disorders

Unfortunately, this duet is not always without problems. Vegetative nervous system disorders can affect our bodies in various ways and have an impact on processes. For example, disorders can lead to insufficient blood pressure regulation, leading to frequent episodes of dizziness and light-headedness. Vegetative disorders can be progressive or reversible, i.e. curable.

The causes for these disorders are variable – the ones occurring most often are illnesses like diabetes or Parkinson’s disease, however. Aside from illness-related changes, age plays a large role in the function of our vegetative nervous system. Over the years, cell functions slowing down leads to problems such as blood pressure disorders, metabolism changes, or dizziness.

What does that mean for us?

Better understanding your own body is always important. Not only can we better understand why we react to specific stimuli in specific ways in this manner, but we can also try to lessen the strain on our bodies! The sympathetic nervous system is important and its function is very useful – but constant tension and stress are not good for our bodies, as we are deprived of energy and other processes are neglected. To maintain equilibrium and not have the sympathetic nervous system active all the time in our stressful everyday lives, it helps to seek out more balance and relief in daily life (for example with meditation) or to provide more time for rest and relaxation.

To keep our vegetative nervous system in working order for as long as possible, it is particularly important to watch our health and support our cells in their tasks! This can decrease the probability of vegetative nervous system disorders in old age.