Control Your Vagus Nerve to Improve Mood, Alertness & Neuroplasticity
Date: 2025-06-23 | Duration: 01:51:15
Transcript
0:00 Welcome to the Huberman Lab podcast where we discuss science and science-based tools for everyday life. I’m Andrew Huberman and I’m a professor of neurobiology and ophthalmology at Stanford School of Medicine. Today we are discussing the vagus nerve. The vagus nerve, or what neuroanatomists call cranial nerve 10, is an extremely interesting nerve because when we hear the word nerve we often think of a small connection between one thing
0:30 and another—the wires of the nerve which of course we call axons. If you didn’t know that, now you know they’re called axons. But actually, the cranial nerve is an extensive pathway; it’s a whole set of connections that link the brain and body. In fact, in many respects, it looks like its own nervous system within the traditional nervous system of the brain and the spinal cord, the connections between spinal cord and muscle. The vagus nerve is so vast. It spreads out through so much of the body.
1:00 And as you’ll learn today, it’s connected to so many interesting different brain areas and has so many interesting different functions that it deserves an entire episode of this podcast. The other great thing about the vagus nerve is it is highly actionable. Meaning what you will learn today, if you already know something about the vagus nerve, is going to change what you know and believe about the vagus nerve. What you hear today will also, if you don’t know or you’re not familiar with the vagus nerve, educate you on the latest about the vagus nerve.
1:30 We’ve learned a lot about the vagus nerve and ways to control the vagus nerve in the last few years. And finally, and perhaps most importantly, the information that you’re going to learn today includes actionable tools that will, for instance, allow you to make yourself more alert when you want to without the use of pharmacology. It will allow you to calm yourself down quickly when you want to on demand and quickly without the use of pharmacology or devices. And it will also allow you to alter your mood for
2:00 the better and indeed to improve your ability to learn. The vagus nerve is that important. It’s involved in that many different things. And the pathways of the vagus nerve, as I mentioned, have been charted in more detail in recent years. And the ways that we can get into the vagus nerve and stimulate its actions in specific ways to achieve those endpoints of improved mood, deeper relaxation, fast relaxation, elevated levels of alertness, and on and on are now very well understood. So, as you can probably tell, I’m extremely
2:30 excited about today’s episode because the vagus nerve is just one of the most fascinating aspects to our nervous system. You have one, I have one. So, let’s figure out how they work and how to put it to work for the better. Before we begin, I’d like to emphasize that this podcast is separate from my teaching and research roles at Stanford. It is, however, part of my desire and effort to bring zero-cost to consumer information about science and science-related tools to the general public. In keeping with that theme, today’s episode does include sponsors. Our first sponsor
3:00 is LMNT. LMNT is an electrolyte drink that has everything you need and nothing you don’t. That means the electrolytes sodium, magnesium, and potassium in the correct amounts, but no sugar. Proper hydration is critical for optimal brain and body function. Even a slight degree of dehydration can diminish cognitive and physical performance. It’s also important that you get adequate electrolytes. Potassium is vital for functioning of all the cells in your body, especially your neurons or your nerve cells. Drinking LMNT dissolved in water
3:30 makes it very easy to ensure that you’re getting adequate hydration and adequate electrolytes. To make sure that I’m getting proper amounts of hydration and electrolytes, I dissolve one packet of LMNT in about 16 to 32 ounces of water when I first wake up in the morning. And I drink that first thing in the morning. I’ll also drink LMNT dissolved in water during physical exercise that I’m doing, especially on hot days when I’m sweating a lot and losing water and electrolytes. LMNT has a bunch of great tasting flavors. I love the raspberry. I love the citrus flavor. Right now, LMNT has a limited edition
4:00 lemonade flavor that is absolutely delicious. I hate to say that I love one more than all the others, but this lemonade flavor is right up there with my favorite other one, which is raspberry or watermelon. Again, I can’t pick just one flavor. I love them all. If you’d like to try LMNT, you can go to drinkLMNT.com/huberman to claim a free LMNT sample pack with a purchase of any LMNT drink mix. Again, that’s drinkLMNT.com/huberman to claim a free sample pack. Today’s
4:30 episode is also brought to us by Joovv. Joovv makes medical-grade red light therapy devices. Now, if there’s one thing that I have consistently emphasized on this podcast, it is the incredible impact that light can have on our biology. Now, in addition to sunlight, red light and near-infrared light sources have been shown to have positive effects on improving numerous aspects of cellular and organ health, including faster muscle recovery, improved skin health and wound healing, improvements in acne, reduced pain and inflammation, even mitochondrial function, and improving
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5:30 all Huberman Lab listeners with up to 400 off. Okay, let’s get familiar with the vagus nerve. The vagus nerve is cranial nerve 10. The vagus nerve is very different than the other cranial nerves because whereas it does have connections with areas on the face, head and neck and deep to those areas too, so throat, etc., it also has connections or I should say it receives
6:00 and provides connections to areas within the body. In fact, it has connections with the head area, the neck area, the chest area, the abdomen, and even a bit lower into the lower intestines. So, the vagus nerve is super extensive in terms of its outputs and its inputs. And I’ll explain what I mean by outputs and inputs in just a moment. But what’s very useful to understand and visualize in your mind anytime we’re talking about the vagus nerve is we’re talking
6:30 about a nerve of many many different pathways that both receives and provides information from essentially all areas of the body down to the base of your pelvis. And that stands in stark contrast from the other cranial nerves which tend to receive information from restricted areas of the body, most typically the head and neck area, and that tend to provide connections to the head and neck area. The word vagus actually translates more or less to vagabond, which means wandering. So early
7:00 neuroanatomists saw that this nerve, cranial nerve 10, had connections to large areas of the body and head and neck and received inputs from lots of areas of the body and decided to call it essentially the vagabond nerve or the vagus nerve. Now even though the word vagabond means essentially wandering and the word wandering suggests random, there is nothing random about the wiring of the vagus nerve. The vagus nerve is incredibly precise in terms of
7:30 where it receives information from and where it provides information to. Now, I want to be very clear what I mean about information. If you’re a biologist, you’ll probably understand some of this. If you’re not, and I have to assume most of you are not, it’s still very important that you understand and it’s very easy to understand that your nervous system, your brain, spinal cord, and of course your nervous system includes all these cranial nerves including the vagus nerve, are carrying different types of information along different pathways. Different neurons or different nerve cells within the vagus
8:00 nerve are receiving or giving different types of information for different purposes. For instance, there is sensory information carried by neurons, nerve cells in your nervous system. Sensory information is information that converts light into electrical signals at the level of your eyes. Then your eyes are providing information to the brain about what’s out in the visual world. That’s sensory information. The same could be said for
8:30 sound waves. That’s sensory information that your auditory system converts to your understanding of speech and sound and music etc. Other neurons control motor functions, literally the movement of your limbs by controlling contraction of your muscles or the movement of your lips or the closing or opening of your airways. So motor information of course can be seen on the surface of the body. I’m moving my hands now. I’m moving my mouth. You don’t even need to see me do that to know that I’m doing that.
9:00 But within our body, we have organs that also need motor control. For instance, our gut. Our gut is not just a passive tube through which food moves. The gut is contracting and relaxing. It’s moving food through from one end to the other. We have our pancreas, we have our liver, we have our spleen. And you might think those are vegetative organs; they just sit there. Maybe the cells do stuff, but they don’t move much. But actually your spleen even has a contractile ability.
9:30 So it can contract to release red blood cells or immune cells into circulation and so on and so forth. Different organs including your muscles but other organs as well need instructions as to when they should move, when they should contract, when they should relax. So we have sensory information that’s carried by essentially one set of neurons in our nervous system. So carrying light information or sound information or as you’ll see in a few minutes chemical information about the acidity of the gut. And we have neurons that
10:00 are considered motor neurons. They control the contraction of muscles or the contraction of these different organs or the encouragement for different aspects of the digestive tract to contract or relax to move food along. So we’ve got sensory neurons and we have motor neurons. And then there are a lot of other neurons as well that we call modulatory neurons that adjust the balance between the sensory information and motor information. We aren’t going to talk so much today about modulatory neurons, but they are an important third category of neuron in
10:30 the nervous system. Now, why am I telling you all this stuff about sensory motor? Because the vagus nerve is also unique in that it is both a sensory pathway and a motor pathway. And this is something that most discussions about the vagus nerve—in fact, I would say 99% of discussions about the vagus nerve that you see online or when you hear about, forgive me, in your yoga classes—by the way, I’m going to touch on how yoga and ancient yogic practices actually managed to tease apart some
11:00 very important functions of the vagus nerve without knowing any of the underlying mechanisms. But it is the case that most of the time when you hear about the vagus nerve out there in the general world or in the