Vagus nerve
The vagus nerve is the longest cranial nerve in the human body and connects the brain with almost all internal organs - heart, lungs, intestines and more. As a central component of the parasympathetic nervous system, it regulates rest, digestion and heart rate. Stimulating it through breathing exercises, meditation or singing can calm the nervous system and strengthen stress resilience.
What is the vagus nerve?
The vagus nerve (Latin: nervus vagus – the “wandering nerve”) originates in the brainstem and runs through the neck, chest, and abdomen. It transmits signals in both directions: about 80% of the fibers carry information from the body to the brain – the body constantly “reports” to the brain on how it is doing.
The Polyvagal Theory
Neuroscientist Stephen Porges developed the Polyvagal Theory, which describes how the vagus nerve regulates three states of the nervous system: social connection and safety, the fight-or-flight response, and freezing in the face of extreme threat. This theory has fundamentally influenced trauma and stress research.
Vagus Nerve Stimulation in Everyday Life
Heart rate variability (HRV) is considered a measure of vagus nerve activity—the higher the HRV, the more flexible and resilient the nervous system. The following practices have been shown to promote vagal tone:
- Slow, deep exhalation (e.g., through pranayama)
- Humming, singing, and humming meditation (Bhramari)
- Exposure to cold, e.g., splashing cold water on the face
- Mindfulness meditation and Yoga Nidra
- Social connection and secure eye contact
What does "good vagal tone" mean?
A high vagal tone means that the parasympathetic system is well regulated - the body can switch quickly between activation and rest. Studies show that people with high vagal tone have fewer inflammatory markers, better emotional regulation and higher social competence.
Can the vagus nerve be overstimulated?
In rare cases, very strong vagus stimulation can trigger brief moments of fainting (vasovagal syncope), e.g. in the event of severe pain or fright. However, the gentle stimulation techniques recommended in everyday life, such as breathing exercises or humming, are harmless.