In recent years, the vagus nerve has become an object of fascination, especially on social media. Vagal nerve fibers, which run from the brain to the abdomen, have been cited by some influencers as the key to reducing anxiety, regulating the nervous system and helping the body relax.
TikTok videos with the hashtag “#vagusnerve” [nervo vago, em inglês] have been viewed over 64 million times, and there are nearly 70,000 posts on the subject on Instagram.
Some of the more popular ones feature simple tricks for “toning” or “reshaping” the vagus nerve, in which people dip their face in ice-water baths or lie on their backs with ice packs on their chests. There are also neck and ear massages, eye exercises and deep breathing techniques.
Now, wellness companies have capitalized on the trend, offering products like “vagus massage oil,” vibrating bracelets and pillow sprays, which claim to stimulate the nerve but have not been endorsed by the scientific community.
Researchers studying the vagus nerve say stimulating it with electrodes can help improve mood and alleviate symptoms in people suffering from treatment-resistant depression, among other ailments.
But are there other ways to activate the vagus nerve? Who would benefit most from this? And what exactly is the vagus nerve anyway? Here’s a look at what we know so far.
What is the vagus nerve?
The term “vagus nerve” is actually shorthand for thousands of fibers. They are organized into two bundles that descend from the brainstem down both sides of the neck and into the trunk, where they branch out to touch our internal organs, said Dr. Kevin J. Tracey, neurosurgeon and president of the Feinstein Institutes for Medical Research at Northwell Health in New York.
Imagine something similar to a tree, whose branches interact with almost every organ system in the body. (The word “vagus” means “wanderer” in Latin.)
The vagus nerve picks up information about how organs are working and also sends information from the brain stem back to the body, helping to control digestion, heart rate, voice, mood, and the immune system.
For these reasons, the vagus nerve — the longest of the 12 cranial nerves — is sometimes called the “information superhighway.”
The Doctor. Tracey likened him to a transatlantic cable. “It’s not a mixture of signals,” he said. “Each sign has a specific job.”
The vagus is the main nerve of the parasympathetic nervous system. Unlike the sympathetic nervous system, which is associated with the body’s “fight or flight” response, the parasympathetic branch helps us to rest, digest, and calm down.
Scientists began examining the vagus nerve in the late 1800s to investigate whether its stimulation could serve as a treatment for epilepsy. They later found that a side effect of nerve activation was an improvement in mood. Today, researchers are examining how the nerve can affect psychiatric disorders, among other conditions.
What does the survey say?
Evidence indicates that stimulating the vagus nerve can help people with epilepsy, diabetes, treatment-resistant depression and PTSD (post-traumatic stress disorder), as well as autoimmune inflammatory conditions like Crohn’s disease or rheumatoid arthritis. Some preliminary research suggests that even the symptoms of long-term Covid may stem, in part, from the action of the virus on the vagus nerve.
“It can feel kind of magical, with all the things he does,” said Eric Porges, an assistant professor in the department of clinical and health psychology at the University of Florida who studies the vagus nerve.
Our understanding is that the vagus nerve “continues to grow in richness and depth,” he said, but much remains to be learned about its functioning.
In the early 2000s, researchers began to show that vagus nerve stimulation could help some severely depressed patients who were unresponsive to other treatments.
A wave of studies followed. In 2005, the Food and Drug Administration (FDA) approved implantable pulse-generating devices, which send electrical signals to the vagus nerve, for use in treatment-resistant depression patients.
Similar devices have also been approved for obesity — to help control feelings of hunger and fullness — and to treat epilepsy. The downside to these devices, however, is that the surgery is expensive and can take months to take effect — sometimes up to a year.
Researchers are recruiting patients for the largest clinical trial ever to examine the extent to which vagus nerve stimulation can help patients with depression who haven’t been able to find relief from other treatments.
The device may be especially useful for those with bipolar depression because there are few treatments for them, said Dr. Scott Aaronson, one of the psychiatrists who led the clinical trial and the scientific director of the Institute for Advanced Diagnosis and Therapeutics, a center at Sheppard Pratt psychiatric hospital that aims to help people who have not improved with conventional treatments and medications.
In general, one of the problems with treating depression “is that we have a lot of drugs that pretty much do the same thing,” Aaronson said. And when patients don’t respond to these drugs, “we don’t have much news.”
However, implanted vagus nerve stimulation is currently not affordable for most people, as insurers have refused to pay for the procedure — with the exception of US Medicare beneficiaries, who participated in the latest clinical trial.
Tracey’s research, which uses internal vagus nerve stimulation to treat inflammation, may also have applications in psychiatric disorders such as post-traumatic stress disorder, said Dr. Andrew H. Miller, director of the Behavioral Immunology Program at Emory University, who studies how the brain and immune system interact and how these interactions can contribute to stress and depression.
PTSD is characterized by heightened measures of inflammation in the blood, he said, which “can influence circuits in the brain related to anxiety.”
In a pilot study at Emory, for example, researchers electronically stimulated the neck skin near the vagus in 16 people, eight of whom received vagus nerve stimulation treatment and eight received a sham treatment.
The researchers found that stimulation treatment reduced inflammatory responses to stress and was associated with a decrease in PTSD symptoms, indicating that such stimulation may be helpful for some patients, including those with elevated inflammatory biomarkers.
Meanwhile, Dr. Porges and his colleagues at the University of Florida patented a method to adjust electrical stimulation of the vagus nerve based on a patient’s physiology. He is now working with the company Evren Technologies, in which he is a shareholder, to develop an external medical device that uses this approach for PTSD patients.
How to measure vagus nerve activity?
Vagus nerve activity is difficult to measure directly because of its complexity. But because some nerve fibers connect to the heart, experts can indirectly measure cardiac vagal tone — the way the nervous system regulates the heart — by looking at heart rate variability, which is the time fluctuations between heart rates, on an electrocardiogram. heart beats.
An abnormal vagal tone – in which there is very little heart rate variability – has been linked to conditions such as diabetes, heart failure and hypertension.
A high variability between heartbeats can mean optimal vagal tone.
How to improve your vagal tone at home?
Holding your breath and soaking your face in cold water can trigger the “dive reflex,” a response that slows your heart rate and constricts blood vessels. Some people who have experienced it have said that it has a calming effect and can even reduce insomnia. Others wrap an ice pack in a cloth and place it on their chest to relieve anxiety.
These specific exercises haven’t been studied enough as methods for managing anxiety or depression, so it’s hard to know if they work. Still, some experts say it’s worth a try.
“It’s certainly one of the most benign things we can do,” said Dr. Aaronson.
But Dr Tracey urged caution, adding that it is difficult to adequately assess risks and benefits without clinical data. “I wouldn’t advise anyone to do any intervention without consulting their doctor,” he said.
“For wellness, try to keep vagus nerve activity elevated through mindfulness, exercise, and rapid breathing,” Tracey said. “All this is very good.”
Translated by Luiz Roberto M. Gonçalves
Chad-98Weaver, a distinguished author at NewsBulletin247, excels in the craft of article writing. With a keen eye for detail and a penchant for storytelling, Chad delivers informative and engaging content that resonates with readers across various subjects. His contributions are a testament to his dedication and expertise in the field of journalism.
