It is important for the survival of the species to have developed different automatic processes, which are spontaneous and do not require our consciousness, because if we took a second longer to carry them out today we would not be here alive reading this article and I would not be writing it. (The tiger would have eaten our great-great-great-grandfather by now.)

These automatic processes occur through the Autonomic Nervous System, which has two divisions: The Sympathetic and Parasympathetic Nervous System.

In the process of Fight or Flight, the Sympathetic is activated, which allows us to defend ourselves against stressors or move away from possible dangers in order to survive: it increases the heart and respiratory rate, sending blood to the muscles and dilating the pupils (to be able to run, attack, have more visual acuity, etc.).

In the process of sleep, digestion and repair of the organism, the Parasympathetic nervous system is activated, which allows us to relax and recover, favors deep sleep: it reduces the heart and respiratory rate, and we can go to rest and have a good digestion (it increases blood flow to internal organs).

Our brain has not yet developed the ability to distinguish between different types of stressors, so it does not differentiate between the boss who yells at us or a lion who wants to eat us for breakfast.

All of the above allowed us to survive in ancient times, being surrounded by wild animals that could end our lives in seconds, tribes that stalked us, etc.

The current problem is that we have overstimulated the sympathetic nervous system because it "believes" that the waste left by the neighbor's dog on the sidewalk is something of life or death (yes, that's how our autonomic nervous system works).

Within osteopathy there is a form of approach called Creaneo-Sacral therapy, which specifically treats structures of the skull and sacrum, favoring the regulation of the nervous system.