Functions of the autonomic nervous system

The vegetative nervous system, also known as the autonomic nervous system, cannot be voluntarily controlled.

It regulates all vital functions, such as breathing, heart rate, blood pres-sure, energy production, digestion and metabolism. 
nervous system is made up of the sympathetic (“tense nerves“) and the parasympathetic (“relaxed nerves“) nervous systems. Both these systems work contrary to one another.


if a person is confronted with a dangerous situation, thus triggering the instinct to run, the sympathetic system (“tense nerves“) becomes much more active than the parasympathetic system (“relaxed nerves“). 

The following reactions are observed in the body:

• The heart will pump faster
• Increase of oxygen supply
• Attention and concentration are heightened
• The body and the mind are in a state of alert
• Pupils are dilated
• Blood pressure rises
• Stress hormones, such as adrenaline, are released
Under such conditions, the body can perform at a much higher level.

Once this stressful situation has passed the parasympathetic system (“relaxed nerves“) will be more active than the sympathetic system (“tense nerves“). Functions such as recovery, regeneration and repair take precedence.

This example of regulation clearly shows the basic functioning of the vegetative nervous system. Increasing age, excessive stress, chronic illnesses or a weakened immune system impair the body’s ability to regulate the nervous system.

Parasympathetic nervous system           Sympathetic nervous system