What is the difference between Sympathetic and Parasympathetic?

Sympathetic Nervous System or SNS controls the responses of the body to a perceived threat, thus responsible for the response of fight or flight. An example of a fight or flight situation is when someone asks you for a confrontation, and whether you will confront that person or not, it is the response of your SNS.

Parasympathetic Nervous System (PNS) on the other hand, is the one controlling the homeostasis and responsible for the rest and digest function of the body. We feel full (and sometimes sleepy) when we eat a good amount of food. It is the PNS that tells us that we have reached our limit and must stop eating for the body to digest the food. During SNS, our body tends to speed up due to the tension while on PNS our body relaxes.

There are two different types of nervous systems in the body. There is the sympathetic nervous system and the parasympathetic nervous system. In most cases, people have heard of the nervous system, but they probably have not heard of the sympathetic nervous system or even the parasympathetic nervous system.

Both of these systems are important to the body and help make you function. However, the critical difference between the two is that the sympathetic nervous system deals with the harm that you may feel are about to be inflicted. This deals with deciding whether to fight or fly away. The parasympathetic nervous system deals with homeostasis and helping the body to rest and relax as a response.