You might wonder why this is not understood by physicians or doctors. I have studied medicine, and if you ask most doctors about the parasympathetic system, they will often say they are unfamiliar with it. This is called A sushumna—the central channel of energy that mirrors the parasympathetic system. Some people refer to it as the autonomic nervous system, which controls functions like heartbeat and breathing. Doctors often say they cannot control or interact with this system.
The Asushumna regulates the heart rate, breathing, and digestion. For example, if a person suffers from constipation, it could turn into diarrhoea as part of a self-correcting process. People who have awakened this energy, or balanced it, often display signs such as dilated pupils, indicating that their parasympathetic system is activated.
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