Of the 12 pairs of cranial nerves that emerge from the brain, the vagus nerve is the longest and most intricate. It transfers data to or from the brain's surface to tissues and organs located in other parts of the body.
The word "vagus," which means "wandering," has Latin origins. The vagus nerve leaves the brain and travels to the neck, chest, and belly, where it affects several organs. It is sometimes referred to as cranial nerve X or the 10th cranial nerve.
We reached out to a Medical Practitioner - Dr. Barbara Harris to explain more to us about this important nerve. According to her, The vagus nerve connects the brainstem to the body and has two clusters of sensory nerve cell bodies. She further explained that this enables the brain to keep track of and gather data on a number of the various bodily functions.
Dr. Barbara further explained, “The vagus nerve and its accompanying structures support a variety of nervous system processes. The parasympathetic and sympathetic portions of the autonomic nervous system are supported by the vagus nerve.
“The nerve transmits motor information for movement throughout the body as well as some sensory processes. In essence, it is a component of a circuit that connects the brain to the neck, heart, lungs, and abdomen (1).”
explained that "vagus" is a Latin word that means wandering. She quickly added that the vagus nerve is the longest cranial nerve, this name is quite fitting, and that it extends from a portion of the colon to the brain stem (2).
Dr. Barbara further informed us that the vagus nerve travels from the brain to the belly through the face and thorax. According to her, the superior and inferior ganglia are the two sensory ganglia (masses of nerve tissue that transmit sensory impulses) found on the vagus nerve.
Dr. Barbara added, “The skin in the ear's concha is innervated by the branches of the superior ganglion. The pharyngeal nerve and the upper laryngeal nerve are two branches that emerge from the inferior ganglion. The laryngeal muscles are innervated by the recurrent laryngeal nerve, which arises from the vagus in the lower neck and upper thorax (voice box)”.
She also mentioned that the vagus also produces branches for the heart, esophagus, and lungs and that the majority of the digestive system and other abdominal viscera are innervated by the vagus in the belly.
Still talking about the course and function of the vagus nerve. She further stated: “The vagus nerve is the cranial nerve with the widest spread. Its pharyngeal and laryngeal branches transmit motor impulses to the pharynx and larynx, while its cardiac and bronchial branches constrict the bronchi and its esophageal branches control the involuntary muscles in the esophagus, stomach, gallbladder, pancreas, and small intestine to promote peristalsis and gastrointestinal secretions.
“Patients with epilepsy or depression who are otherwise unable to receive treatment occasionally use vagus nerve stimulation; the procedure has also been investigated for illnesses like Alzheimer's disease and migraine (3).”
Dr. Barbara described the two parts of the sensory functioning of the vagus nerve as the somatic elements which are feelings experienced in the muscles or on the skin, and the visceral elements which are sensations experienced in the body's organs.
She further listed the following as the sensory functions of the vagus nerve:
Dr. Barbara added that apart from these sensory functions, the vagus nerve also performs motor functions such as:
She added that the function of the vagus nerve also extends to some other effects such as:
We asked Dr. Barbara why the vagus nerve is such an important nerve in the body. She stated that “The parasympathetic nervous system's main vagus nerve affects a variety of bodily functions, including breathing, heart rate, swallowing, sneezing, digestion, appetite, immunological reactions, and even orgasm”
Furthering her explanation of the importance of the vagus nerve, she added, “The great range of abilities possessed by the vagus nerve is a result of the variety of neuron cell types at its disposal. These enable the neuron to gather many kinds of sensory signals from various organs. Some, for example, detect chemical signals like blood oxygen levels or bacterial secretions in the colon, while others detect mechanical signals like blood vessels and gut stretching.
“As a result, the brain primarily receives information about what is happening in the rest of the body via the neurons in the vagus nerve. To assist maintain the internal status quo, the brain analyzes this information and takes appropriate action. The less common neurons that send signals in the opposite direction, however, also serve significant roles in the gut-brain axis as well as in a few mouth and throat muscles that are involved in speech and the gag reflex”
Dr. Barbara explained, stating that there are probably still tasks that we haven't discovered for the vagus nerve because its activities are so varied and many. She added that a fast-beating heart can be slowed down or heart palpitations can be calmed by performing "Valsalva maneuvers," which doctors occasionally recommend. Coughing, straining like you're on the toilet, or perhaps most bizarrely doing a handstand are a few examples of these behaviors (4).
Talking about vagus nerve stimulation, Dr. Barbara described neuromodulation as a therapy that modifies nerve activity, including vagus nerve stimulation (VNS). To stimulate the vagus nerve, a device that regularly emits small electrical pulses to the brainstem through the neck is implanted. When the electrical charge reaches the brainstem, it is discharged to various parts of the brain to alter how brain cells function.
“Vagus nerve stimulation acts as your heart's pacemaker. In actuality, VNS has sometimes been referred to as a pacemaker for the brain. When other conventional treatments have failed, you and your healthcare provider may discuss the possibility of VNS as a therapy option. Only a small percentage of people with epilepsy or depression who are unresponsive to treatment can use VNS. VNS has more recently been approved as a rehabilitation tool for a limited number of stroke victims (5)”, she added.
Describing how it is done, she said the left vagus nerve is usually connected to a device that is surgically implanted under the skin of the chest - a procedure she termed traditional vagus nerve stimulation. When the gadget is turned on, electrical signals go up the left vagus nerve to the brainstem and then to certain regions of the brain. Since it's more likely to include fibers that provide nerves to the heart, the right vagus nerve isn't employed.
Talking about its use in the treatment of epilepsy, depression, and pain, she described the use of new, noninvasive vagus nerve stimulation devices that don't require surgical implantation and have received approval in Europe. The Food and Drug Administration recently gave the green light to a non-invasive gadget for the treatment of cluster headaches in the US (6).
Dr. Barbara went into detail on the various ways to stimulate the vagus nerve, she stated that vagus nerve stimulation (VNS) has been used to treat seizures in people with epilepsy. This medical technique inserts a device within the body to use electrical impulses to assist activate the vagus nerve.
Adding to this, she explained that it can be utilized by those with depression who have not responded well to conventional forms of treatment. She talked about the ongoing research into the potential benefits of VNS for conditions like multiple sclerosis, migraines, and Alzheimer's disease. She also added that recent studies have shown that COVID-19 may negatively affect the vagus nerve in people who have long-lasting voice issues, dizziness, and low blood pressure (7).
She listed out the following ways through which you can stimulate your vagus nerve:
Use this technique to focus on deep breathing and to help you relax. Try lengthening your exhales during meditation such that they are longer than your inhales. Your heart rate will slow down as a result. Meditation can control your autonomic nervous system. It effectively reduces rapid breathing, a fast heartbeat, and cortisol levels. For the same benefits, yoga can be beneficial as well. Just be careful to keep your breathing in mind.
Reflexology, a form of massage, has been shown in studies to improve vagal tone and even lower blood pressure. Some of the increased vagus nerve activity can be decreased by massage. Try turning your ankle, using little strokes to rub your sole, and gently moving your toes back and forth to give yourself a foot massage.
Exercise and movement can have an impact on your vagus nerve, according to a study. Your vagus nerve activity can be elevated and your heart rate variability improved with interval exercise and endurance training. Exercise balances your sympathetic nervous system activity and parasympathetic nervous system response to improve your cardiovascular and respiratory health.
You may have seen a well-known congresswoman try this theory by submerging her head in a basin of ice water to reduce stress lately on Instagram Live. Additionally, many professional athletes employ cold water immersion to enhance their momentary relaxation.
According to research, submerging yourself in cold water can reduce stress by decreasing your heart rate and sending more blood to your brain. Try taking a cold shower or applying an ice pack to your face or neck.
We can be inspired by music, find delight in it, and let our feelings out. There is conflicting evidence regarding how music affects the vagus nerve. Your vagus nerve runs through your inner ear and is related to your vocal cords, the muscles in the back of your throat, and your inner ear. Try humming, singing, or simply relaxing with some calming music. Your vagus nerve might be stimulated by those noises and vibrations (7).
The following benefits of stimulating your vagus nerve were outlined by Dr. Barbara:
We asked Dr. Barbara about the various conditions that can be managed using vagus stimulation. She briefly described the use of vagus stimulation in the treatment of the following condition:
Rheumatoid arthritis (RA), an anti-inflammatory disorder that causes pain and swelling in the joints as well as other symptoms all over the body, may be less severe with the use of VNS, according to some research.
After evaluating inflammation markers in 30 participants who utilized a VNS device to help control their RA for 12 weeks, researchers reported their findings in 2021. They discovered proof that their DAS28-CRP levels, a marker of inflammatory response in the body, decreased in a "clinically relevant" manner.
While encouraging, additional research is required to substantiate if VNS can safely and efficiently manage RA in a larger population.
Some people have been researching various methods of stimulating the vagus nerve to improve mental health, especially if VNS can assist manage depression.
These consist of:
People with a strong vagal tone may find it easier to relax after a stressful event and their bodies may be better able to manage inflammation and digestive problems. Vagal response diminishes with age. It might also be more capable of controlling blood sugar.
However, there isn't enough data to substantiate the universal applicability of all these tools and methods. Always consult your doctor before attempting a novel treatment approach because it might not be appropriate for you (2).
The FDA approved vagus nerve stimulation for the treatment of refractory epilepsy in 1997. This entails implanting a tiny, electrical device—similar to a pacemaker—into the person's chest. The device connects to the vagus nerve through a small wire known as a lead. Under general anesthesia, the gadget is surgically implanted into the body. The brain is then periodically stimulated with electrical impulses throughout the day at regular intervals via the vagus nerve to lessen the frequency or end seizures (1).