Dear Doctors: I keep reading about how the vagus nerve has a lot to do with things like mood, digestion and keeping your brain healthy. Where is it located? Supposedly there is even a kind of technique where rubbing it can help with anxiety and irritable bowel syndrome? I want to know if that is true.
Dear Reader: The vagus nerve is a long, branching and meandering nerve that serves as an information superhighway. It is the longest and most complex of the 12 cranial nerves. Although referred to in the singular, there are actually two vagus nerves, one on each side of the body. They begin in the brain stem, run through the face, neck and chest, and reach into the abdomen, where they terminate in the colon. The vagus nerve not only divides and branches out (its name derives from the Latin word for “wandering”), but it also connects to and interacts with other nerves in the body. As a result, it plays a leading role in digestion, mood, heart rate and immune response, and it is central to the complex network of connections known as the gut-brain axis.
The vagus nerves transmit information to the brain about movement or sensation from a variety of organs and physical regions. These include the heart, digestive system, lungs, larynx, ears, esophagus, sinuses and tongue. It has led the vagus nerve to become the focus of study for possible treatments of a number of diseases and conditions. One approach is known as vagus nerve stimulation. It involves sending tiny pulses of electricity to a specific area of the vagus nerve via an implanted device. This stimulation prompts the nerve to send signals to the brain, which results in beneficial changes to brain activity.
The FDA has approved vagus nerve stimulators for several conditions. One for epilepsy sends impulses to the region of the brain associated with seizures. That area also affects mood, and the device has also been approved for use in people with treatment-resistant depression. Another stimulation device, which creates new neural pathways, helps stroke patients regain movement in their arm or hand. A device for cluster headaches is also FDA-approved. While there is evidence that vagus nerve stimulation may help manage irritable bowel syndrome, a device for that condition has not yet been approved. More recent research is looking into the treatment for Alzheimer’s disease.
There are several ways to stimulate the vagus nerve naturally. The nerve pair begins its journey through the back of the neck, and some people find that massaging that area, including under and around the ears, can help ease feelings of anxiety. The vagus nerve also runs through the diaphragm, which means the deep inhales and deliberate exhales of yoga breathing give them a natural massage. If you have a blood pressure device at home, you can do before and after readings to check on the effects of the massage.
You may have noticed that external vagus nerve stimulators are now being offered for sale. At this time, there is not enough credible information about either their efficacy or, more important, their potential health risks for them to be considered safe for at-home use.
(Send your questions to [email protected], or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)
