The vagus nerve plays a central role in your emotional and physical health. The term vagus is Latin for “wandering,” an apt descriptor as this nerve extends from the brainstem down into your stomach and intestines, innervates your heart and lungs, and connects upward into your throat and facial muscles.You can think of the vagus nerve as a bi-directional communication system helping you stay in touch with your sensations and emotions.
The vagus nerve plays a key role in your body’s second or enteric brain that exists within your gastrointestinal system. Nerve fibers within your stomach and intestines not only regulate digestion, peristalsis, and elimination; but also produce the same neurotransmitters found in the brain. Your gut is capable of responding to stress even before you have consciously registered a trigger. By then, stress chemicals may already have been communicated between your digestive system and your brain through the vagus nerve.
The nervous system is constantly scanning for cues to determine whether situations or people are safe, dangerous, or life threatening. Unconsciously, we are looking for these cues within our own body, in the environment around us, and in the body language, facial expressions, or voice tones or other people. Without realizing it, your belly constricts, heart rate increases, and muscles in your arms or legs grow tense. You might be reacting to the sound of your partner’s voice, a smell of cologne, or the look on a stranger’s face.
Approximately 80% of vagus nerve fibers travel from the body to your brain. This explains why we cannot think our way out of trauma reactivity; rather, we must work with the body to maximize healing.