What is parasympathetic activation?

Parasympathetic activation refers to the activation of the parasympathetic nervous system, which is sometimes called the "rest and digest" system. It is responsible for promoting states of relaxation and calm. Activation of this system decreases heart rate, reduces blood pressure, and stimulates digestion among other functions. This activation is essential for maintaining balance in the body’s response to stress and relaxation.

For example, during cold water immersion, the dive reflex initiates a parasympathetic response which brings about a calming relaxation response, slowing down heart rate and other body functions to conserve energy 1. Similarly, when listening to music, engaging in conscious relaxation, or practicing certain breathing techniques, the parasympathetic nervous system is activated, contributing to increased relaxation and lowered stress levels 2.

In essence, the parasympathetic nervous system helps to maintain homeostasis in the body by counterbalancing the excitatory effects of the sympathetic nervous system. It plays a key role in stress management and overall well-being.