The vagus nerve, the longest nerve in the body, controls our fight-or-flight response and gets knocked out of kilter after trauma. Cate Montana investigates how to restore your calm
Dr Arielle Schwartz (drarielleschwartz.com), a clinical psychologist specializing in trauma recovery in Boulder, Colorado, has lots of stories to tell about trauma and the health effects of vagal nerve stimulation.
For example, one patient who had to identify her father’s body after he committed suicide developed gastroparesis afterward—a debilitating condition marked by nausea, vomiting and abdominal pain. Eventually the condition got so bad, she couldn’t leave her house.
“When she first came in, she couldn’t drive her own car,” says Schwartz. “During the session she was feeling so anxious and nauseous, we didn’t even talk about any of the trauma. We couldn’t.
“Instead, I taught her diaphragmatic breathing (which stimulates the vagus nerve), and we did that together. Within that single session, she was able to cut the level of anxiety and that physiological trouble down by half. That’s huge.”
Schwartz helped the patient examine specific trauma during later sessions, adding in somatic (body) work and EMDR therapy. EMDR is eye movement desensitization and reprocessing, a form of energy medicine designed to reduce trauma-based stress by remembering the trauma while focusing the eyes on a particular point.
“But we only brought those therapies in when she was ready,” Schwartz says. “We had to get her nervous system stabilized first so that she was sleeping at night and better digesting her food, because trauma disrupts all of that.”
Schwartz taught the woman at-home techniques involving vagus nerve stimulation, which she could use between sessions when she felt her physical symptoms and anxiety worsening. Within three months, she was out of the house and back driving, able to lead a relatively normal life.
Stimulating the vagus nerve is a powerful and immediate way of dealing with PTSD symptoms, anxiety and stress because this nerve is the primary conductor of communications between the brain and the body, carrying both motor and sensory information. Vagus is Latin for “the wanderer.”
The longest cranial nerve in the body, it originates in the brain stem, running down through the neck, chest and abdomen, all the way down to the colon. A major driver of the autonomic (involuntary) nervous system, it controls a wide variety of body functions such as heart rate, blood pressure, digestion, respiration, sweating, salivation, the cough and gag reflexes, swallowing and vocal coordination.
There are actually two nerves, one running down the right side of the body and the other down the left side, normally referred to collectively as “the vagus nerve.” An over-stimulated or under-functioning vagus nerve results in a set of medical conditions broadly known as dysautonomia, the malfunction of nerves, including the vagus nerve, that regulate involuntary functions.
Believed to affect over 70 million people worldwide, dysautonomia is regularly misdiagnosed and may take years to be identified.
As a child, Joy experienced domestic violence. In adulthood, after the tragic loss of her five-year-old daughter Melia and then, three years later, the unexpected death of her husband from an aneurysm, Joy spent the next few years in a state of shock.
“It was crazy,” she says. “It almost destroyed me. I couldn’t sleep. My nerves were frazzled. I kept having these heart palpitations, anxious sweating, nausea and headaches, and chronic pain. Even though I remained highly functioning as a construction architect, inside I was shaking to the bone.”
Diagnosed with complex PTSD, she went to several medical doctors for help. But the one-size-fits-all, “standard of care” approach failed to provide what she needed.
“They all kept saying, ‘Here, take these antidepressants.’ And I was like, ‘I don’t want antidepressants because I’m not depressed.’ And they would say, ‘Of course you’re depressed. Your child and husband died.’ And I was like, ‘Actually, this is different. Yes, I’m grieving, but I’m not depressed. I know you might find that hard to comprehend, but I need help for my nerves.’ And they just had no clue what to do to help me.”
Eventually she went to a psychiatrist who was also a pain specialist. But the result was exactly the same: endless rounds of antidepressants and pain medications.
“No one could help me with the trauma piece,” she says. “No one seemed to understand that what was going on with me was physiological. My nervous system was dysregulated. I was in fight or flight most of the time. And that was driving the emotional piece in a vicious circle.”
After 18 years of debilitating symptoms and frustration, in 2020 Joy attended an embodiment conference and heard Dr Arielle Schwartz speak.
“I was so blown away,” she says. “She was talking about PTSD and trauma as neurological, physiological and neurobiological conditions, and I was like, ‘Oh, my God, she’s talking about me! This is the missing link!'”
Joy took classes from Schwartz and then started private sessions, learning a variety of techniques to calm the vagus nerve and her autonomic nervous system. The techniques included mindful movement and therapeutic yoga for trauma healing and increased vagal tone.
These were specific yoga postures designed to gently stimulate the vagus nerve by opening the chest, throat and belly. Joy also learned self-massage on specific acupressure points for the vagus nerve, breathing techniques and EMDR.
One of her favorite and one of the most effective techniques she learned was sounding. “You place your hands over your ears and put your thumbs on your neck near the vagus nerve and start humming and sounding,” she says.
“The sound Arielle gave me immediately that first session was buzzing, where you’ve got your hands over your ears and make buzzing sounds like a bee. And then put your lips together and blow like when you’re teaching a kid to swim with their face in the water. It was amazing.”
Within a year, Joy says, her life had changed. She even started taking lessons to become a trauma and grief yoga practitioner so that she could turn around and help others the way she had been assisted.
“It’s about establishing a sense of self-agency and self-advocacy,” she says. “When you’re traumatized, you can’t slow down enough to listen to your body. That’s the key. That and knowing how to self-regulate.
“When we’re able to bring our nervous system into a state that is relaxed yet alert, we’re able to feel better, think better and be receptive to learning while expanding our capacity for growth and ability to open to new ideas and experiences for ourselves and our relationships with others. When it comes to trauma, I figure the polyvagal and EMDR approach to healing are where the rubber meets the road.”
Studies show that vagus nerve stimulation mitigates a large number of serious conditions that negatively affect our health and well-being. Here is a listing of current treatment approaches.
Conscious breathing. One of the most direct ways we can stimulate the vagus nerve is with the breath, and studies show that a low respiration rate and a low inhalation/exhalation ratio increases vagal tone.1
“When we’re stressed and in the ‘fight or flight’ mode, we’re doing shallow upper chest breathing or even unconsciously holding our breath,” says Dr Arielle Schwartz, “and that sends the message up to the brainstem that we’re not feeling safe right now and our brain is responding to that under the radar of conscious awareness.”
When not under stress, most people take seven to 13 breaths per minute. If you do a simple five-count inhale and a five-count exhale, you can drop your respiration down to six breaths a minute.
“When we do that, we’re slowing everything down and we’re changing the relationship between oxygen and carbon dioxide in the bloodstream,” Schwartz says. “That begins to stimulate chemoreceptors to pick up on that change and send a message via the vagus nerve back up to the brain and that says, ‘Hey, we’re calming down, there’s no threat right now.’ And your whole system relaxes and slows down.”
Cold water treatment. Another classic vagus nerve stimulation technique is cold water exposure, says Schwartz. It can be a cold washcloth or some ice cubes wrapped in a plastic bag with a washcloth around it. If you’re up for it, you can jump in an ice-cold bath or shower.
The acute body awareness that the sharp temperature shift creates and the cold itself interact with the vagus nerve, sending a signal back to your brain that you’re present and aware and things are under control.
Yoga. Studies show that yoga significantly reduces PTSD symptoms just as well as psychotherapeutic and psychopharmacologic interventions.2 Schwartz has been teaching applied polyvagal trauma yoga for years.
“Mindful movement is so important,” she says. “Feeling a contraction across the chest and then an opening across the chest, lifting your heart and then curling your back as in a cat/cow movement in yoga, stimulating where the vagus nerve is passing through the chest and across the diaphragm as you contract there and open in the belly and in the throat works so well. You can do that kind of vagus-stimulating movement seated in a chair.”
Humming and various vocalizations. The vagus nerve is near the vocal cords and inner ear, so the vibrations you create when you hum can influence your nervous system states. Hum, create whatever sound you feel called to produce, buzz like a bee. Notice the sensations in your chest, throat and head. Notice how your body and nervous system calm down.
Valsalva maneuver. Studies show that this move mitigates stress-related heart arrythmias.3 To do the maneuver, close your mouth, hold your nose and blow the air out as if you are trying to pop your ears while coming down from altitude.
“This creates a little bit of pressure where the vagus nerve passes through the areas around the heart and lungs, and you will feel that in the chest,” says Schwartz.
“When you let go of that held breath, the whole body responds, feeing immediately refreshed like you just woke up from a nap!”
Cough hard. This builds up pressure in your chest, affecting the vagus nerve.
Havening. Studies show that acupressure provides immediate anxiety relief.4 A polyvagal approach to calming and restoring a sense of safety in the body, “havening” is a process of firm self-touch along the arms and legs and various acupressure points affecting the vagus nerve for stress reduction.
Connection. Reach out for connection with others who are in a healthy state of mind. It doesn’t have to be physical. Just picking up the phone or texting someone you trust can help initiate regulation of your body and mind. Relationship evokes playfulness and creativity and relaxes us into a trusting bond with another person.
Probiotics. “Preliminary evidence” shows that gut bacteria can positively influence mood and anxiety due to their effects on vagus nerve activity. It is believed that the vagus nerve serves as a signaling/communication pathway between gut bacteria and the brain.5
One therapeutic system Schwartz uses is polyvagal therapy, developed by Dr Stephen Porges, professor of psychiatry at the University of North Carolina and founding director of the Traumatic Stress Research Consortium at Indiana University (polyvagalinstitute.org). The creator of several trauma intervention protocols, he coined the term neuroception to describe the autonomic nervous system’s constant, acutely sensitive “scanning” for danger—a sensing capacity vastly more subtle than sense perception that completely bypasses normal awareness.
Porges identified three pathways of neuroceptive response:
Deb Dana, a polyvagal practitioner and associate of Porges, describes the way these three pathways interact like this: “When we are firmly grounded in our ventral vagal pathway, we feel safe and connected, calm and social. A sense (neuroception) of danger can trigger us out of this state and backwards on the evolutionary timeline into the sympathetic branch. Here we are mobilized to respond and take action.
“Taking action can help us return to the safe and social state. It is when we feel as though we are trapped and can’t escape the danger that the dorsal vagal pathway pulls us all the way back to our evolutionary ancient vertebrate beginnings. In this state, we are immobilized. We shut down to survive. From here it is a long way back to feeling safe and social and a painful path to follow.”
Deb Dana (rhythmofregulation.com) describes the kind of thoughts, actions and health conditions that characterize each state of autonomic nervous system activation.
Because the vagus nerve is involved in so many bodily functions—heart rate, digestion, respiration, vascular tone, vocalization, etc.—symptoms of deteriorating vagal nerve tone are many and varied. Here are early indicators.
Anxiety and depression. Poor vagus nerve tone is associated with impaired monoamine neurotransmission in the brain (monoamine neurotransmitters are neurotransmitters and neuromodulators like serotonin, dopamine and norepinephrine); the dysregulation of activity between the hypothalamus, the pituitary gland and the adrenals; reduced neuronal plasticity; and chronic inflammation in the brain. All of these conditions are triggers for depression.1 Because the vagus nerve is responsible for regulating the sympathetic nervous system and the body’s response to stress, poor vagus nerve tone can also cause chronic anxiety.2
Headaches, migraines and seizures. Fibers from the vagus nerve intertwine with those of the trigeminal, facial, glossopharyngeal and hypoglossal nerves and are believed to control the brain’s headache pain pathways. When the vagus nerve is out of whack, headaches, cluster headaches, migraines and seizures can occur.3
Bradycardia, tachycardia, arrhythmia. Poor vagal tone can negatively affect heart rate variability because the vagus nerves are less capable of carrying signals from the brain regulating your heart rate. This can result in a slow heartbeat (bradycardia), a rapid heartbeat (tachycardia) or an irregular heartbeat.
Dizziness and/or fainting. Poor vagal tone negatively affecting the cardiovascular system can lead to episodes of extreme low blood pressure, resulting in dizziness and even fainting.
Difficulty swallowing. The tongue and automatic esophageal contractions may become compromised.
Chronic dry mouth and throat accompanied by dry cough. Since the vagus nerves are involved in regulating the salivary glands, poor tone may result in dry mouth and cough.
Vocal changes. There can be hoarseness, difficulty coordinating the tongue during speech and a sense that something is wrong with the throat.
Gut issues. Constipation, stomach cramping, indigestion (including acid reflux), irritable bowel syndrome (IBS) and leaky gut can be indicators of poor vagal tone.
Brain function. Brain fog, poor memory, poor concentration, learning disabilities, chronic fatigue and headaches can all be indicators of poor vagus nerve function.
Inflammatory conditions. Chronic inflammation, rheumatoid arthritis and compromised immune function are symptoms.
Long known as a powerful treatment for epilepsy, vagus nerve stimulation (VNS) is the subject of numerous clinical trials exploring its potential use for treating a wide variety of other health disorders, such as PTSD, treatment-resistant depression,4 anxiety, migraines,5 arthritis,6 cardiovascular issues,7 inflammatory bowel disease,8 Parkinson’s, autism, traumatic brain injury and stroke.9 VNS is also being studied for use in mitigating inflammation-based diseases, asthma attacks, chronic pain,10 and even Covid-19.11
“Because the autonomic nervous system typically functions automatically without our sensing it or having any volitional control, when our system is dysregulated, it can feel like these things—all these resulting illnesses—just happen to us,” says Schwartz. “Rather than being in mindful connection with our bodies, seeing ourselves as the conductor of the body and feeling in concert with the body, most people end up feeling like they’re fighting with it.
“Using methods to influence vagal tone by consciously interacting with the vagus nerve allows us to be in concert with our bodies. We can start to rebuild the mind-body relationship, which means rebuilding a sense of trust with ourselves and within ourselves. At this epic point in the world, we all need this kind of knowledge so badly.”
Introduced in the 1990s as a treatment for epilepsy, electrical vagus nerve stimulation is used to amplify weak vagus nerve activity and modulate the nerve’s connection with the brain.
Implanted VNS devices. Often referred to as “pacemakers for the brain,” implanted vagus nerve stimulation devices are battery-operated devices that send extremely mild pulses of electrical energy to the brain stem through the vagus nerve in the neck. (The pulses are below the threshold of conscious sensation.)
Upon reaching the brain stem, the electrical charges are diffused throughout different areas of the brain. Currently in the US, the use of implanted VNS devices is limited to patients suffering from treatment-resistant epilepsy or treatment-resistant depression and as a rehabilitation aid post-stroke.1
During surgery, device leads are implanted beneath the skin of the neck and hooked up to the vagus nerve and the generating device, which is implanted beneath the collarbone. Electrical pulses start at a low setting determined by the doctor and are gradually increased as needed.
Most patients experience an improvement in their symptoms after six months, and improvement continues, on average, for two years. If needed, the VNS device can be surgically removed.
External tVNS devices. A small, transcutaneous (through the skin) device that is wearable can also stimulate the vagus nerve. The generator is pasted to the body inside your clothing, with leads running up the left and right side of the neck, clipping to the tragus of the ear (the small, pointed protuberance in front of the concha on the outside of the ear next to the temple).
Similar to an implanted device, it sends regular mild pulses of electricity into the vagus nerve that are imperceptible. Unlike the implants, external devices can be used for as little as 15 minutes of stimulation per day or up to several hours, as needed. Most people feel some sense of symptom relief after two weeks.
tVNS devices are primarily promoted as increasing “general wellness” while providing stress relief, a strengthened immune system, improved digestion and a balanced parasympathetic nervous system. However, a recent study conducted with six patients suffering from rheumatoid arthritis found that tVNS use inhibited production of TNF (tumor necrosis factor, a substance produced by cells) and two other inflammatory cytokines (small proteins) in healthy subjects, reducing systemic inflammatory responses in patients with rheumatoid arthritis.2
NOTE: tVNS devices should not be used to treat depression, epilepsy or any other medical condition.