Control Your Vagus Nerve to Improve Mood, Alertness & Neuroplasticity
Dr. Andrew Huberman explains the vagus nerve's extensive role in regulating mood, digestion, alertness, and learning. He provides actionable, science-based tools to leverage vagal pathways for rapid calming, improving heart rate variability (HRV), enhancing focus, and boosting mood and neuroplasticity.
Deep Dive Analysis
12 Topic Outline
Introduction to the Vagus Nerve and its Broad Functions
Cranial Nerves: Vagus Nerve's Unique Extensive Pathways
Sensory (Afferent) vs. Motor (Efferent) Vagus Nerve Pathways
Vagus Nerve's Role in Sympathetic and Parasympathetic Systems
Vagus Nerve Motor Outputs and Autoregulation
Heart Rate Variability (HRV) and Vagal Control
Aging, Declining HRV, and Counteracting with Vagal Tools
Vagus Nerve Activation for Alertness and Motivation via Exercise
Adult Neuroplasticity, Learning, and Acetylcholine
Serotonin: Gut-Brain Axis and Mood Regulation via Vagus Nerve
Improving Mood and Gut Health with Fermented Foods and Tryptophan
Calming Down via Vagus Nerve: Neck Stretch and Humming
8 Key Concepts
Vagus Nerve (Cranial Nerve 10)
An extensive neural pathway linking the brain and body, unique among cranial nerves for its widespread connections to the head, neck, chest, and abdomen. It acts as a bidirectional superhighway carrying both sensory and motor information, unlike the common misconception of it solely being a calming pathway.
Sensory (Afferent) Pathways
These pathways, comprising about 85% of the vagus nerve, collect information from the body's organs (viscera, lungs, heart, gut) and transmit it up to the brainstem. This information includes both mechanical signals (e.g., gut distension, lung expansion) and chemical signals (e.g., gut acidity, serotonin levels).
Motor (Efferent) Pathways
These pathways originate in brainstem nuclei, like the nucleus ambiguous, and send instructions back to the body's organs. They control functions such as heart rate deceleration and organ contraction/relaxation, allowing for deliberate control over bodily states.
Autonomic Nervous System Seesaw
The balance between the sympathetic (alertness, fight or flight) and parasympathetic (rest and digest, calm) nervous systems. The vagus nerve, while classified as parasympathetic, contains pathways that can either increase alertness or induce calm, depending on which branch is activated.
Heart Rate Variability (HRV)
The variation in time between heartbeats, which is a positive indicator of health, longevity, and performance. Higher HRV reflects a robust vagal pathway that can effectively decelerate heart rate, especially during exhalation, and is linked to better auto-regulation.
Adult Neuroplasticity
The brain's ability to change and rewire itself in response to experience throughout adulthood. Unlike childhood plasticity, adult neuroplasticity requires both alertness and focused effort, and is significantly enhanced by specific vagal nerve activations that release key neuromodulators.
Acetylcholine
A neuromodulator released from the nucleus basalis in the brain that acts as a 'gate' or 'spotlight' for neuroplasticity. Its release makes the brain more receptive to learning and rewiring, a process that can be stimulated non-pharmacologically via vagus nerve activation.
Gut-Brain Serotonin Axis
A communication pathway where serotonin produced in the gut (90% of the body's total) influences serotonin levels in the brain, impacting mood and well-being. The vagus nerve serves as the critical link, relaying signals from gut serotonin to the brain's dorsal raphe nucleus, which then releases serotonin.
9 Questions Answered
The vagus nerve (cranial nerve 10) is an extensive neural pathway connecting the brain and body, from the head and neck down to the lower intestines. It's crucial because it's involved in regulating mood, digestion, alertness, and learning, with both sensory and motor functions.
No, this is a common myth. While some vagal pathways do induce calm, others can increase alertness and sympathetic nervous system activity, depending on which specific branch is activated and the context.
The fastest way to calm down is by performing a physiological sigh: two inhales through the nose (the second short and sharp) followed by a long, slow exhale through the mouth until lungs are empty. This rapidly shifts the autonomic nervous system towards calm.
You can improve HRV by deliberately extending your exhales throughout the day, even 10-20 times. This strengthens the vagal pathway that decelerates heart rate, improving both waking and sleeping HRV.
Engage in physical activity that uses large muscles, especially the legs and trunk. This stimulates the adrenals to release adrenaline, which then activates vagus nerve receptors, leading to a cascade that increases brain alertness and motivation.
High-intensity exercise activates the vagus nerve, which in turn triggers the release of norepinephrine (for alertness) and acetylcholine (for focus and plasticity) in the brain. This creates an enhanced window for learning and rewiring neural circuits, especially when followed by good sleep.
While most serotonin is made in the gut and stays there, its levels are communicated to the brain via the vagus nerve. Sufficient gut serotonin (supported by healthy microbiota and tryptophan intake) stimulates vagal afferents, leading to serotonin release in the brain's dorsal raphe nucleus, impacting mood.
Ingesting 1-4 servings of low-sugar fermented foods daily (like kimchi, sauerkraut, quality yogurts, kefir, kombucha) can improve gut microbiota. This, combined with sufficient dietary tryptophan, promotes gut serotonin production, which then signals the brain via the vagus nerve.
Yes, two other methods include a specific neck stretch (pushing elbows down, turning head up and to the side) and extended humming, emphasizing the 'h' sound to create deep vibrations in the throat and chest. These mechanically activate vagal fibers to induce a calmer state.
14 Actionable Insights
1. Physiological Sigh for Rapid Calm
Perform a physiological sigh by taking two inhales through the nose (first longer, second sharp) followed by a long, to-lungs-empty exhale through the mouth. This is the fastest way to activate the parasympathetic nervous system and shift the autonomic nervous system towards calm by adjusting the carbon dioxide-oxygen ratio and decelerating heart rate.
2. Extended Exhales for HRV
Throughout the day, deliberately extend your exhale 10-20 times, anytime it occurs to you, to pump the brake on your heart rate. This strengthens the vagal pathway, increasing heart rate variability (HRV) during both wakefulness and sleep, and improving auto-regulation.
3. Physical Activity for Alertness
Engage in physical activity involving large muscles (legs, trunk), such as jumping, resistance training (6 reps or less near failure), or sprinting. This releases adrenaline, which activates the vagus nerve to increase brain alertness, motivation, and focus, helping overcome lethargy and brain fog.
4. Exercise for Enhanced Neuroplasticity
Schedule cognitive learning sessions (e.g., language, piano) in the one to four hours after high-intensity exercise that leaves you energized but not exhausted. This stimulates the vagus nerve to release norepinephrine (alertness) and acetylcholine (focus), which are crucial triggers for adult neuroplasticity and learning.
5. Diet for Gut-Brain Serotonin
Ingest one to four servings of low-sugar fermented foods daily and ensure sufficient dietary tryptophan intake (e.g., dairy, white turkey meat). This promotes healthy gut microbiota, which produce short-chain fatty acids essential for converting tryptophan into gut serotonin, signaling via the vagus nerve to stimulate serotonin release in the brain for mood and well-being.
6. Extended “H” Hum for Relaxation
Hum by extending the “h” sound (e.g., “hhhhhmmmm”) to create a deep vibration that moves from the back of the throat down into the chest and diaphragm. This mechanically activates specific vagus nerve branches, driving a parasympathetic response and slowing heart rate for deep relaxation.
7. Roca Red Lens Glasses for Sleep
Wear Roca red lens glasses in the evening after sundown to filter out short wavelength light from screens and LED lights. This ensures normal, healthy increases in melatonin and low cortisol levels, aiding calm and improving the transition to sleep.
8. Element for Hydration & Performance
Dissolve one packet of Element (electrolytes without sugar) in 16-32 ounces of water upon waking and during physical exercise, especially on hot days. This ensures adequate hydration and essential electrolytes (sodium, magnesium, potassium) for optimal brain and body function.
9. Function Health for Lab Insights
Utilize Function Health for comprehensive lab testing of over 100 biomarkers. This provides insights into heart, hormone, immune, and nutrient health, as well as toxin levels, with analysis and recommendations from expert doctors.
10. Juve Red Light Therapy
Use a Juve whole body panel three to four times a week and a handheld light at home and while traveling. Red and near-infrared light have positive effects on cellular and organ health, including faster muscle recovery, improved skin health, reduced pain, and enhanced mitochondrial function.
11. Neck Stretch for Calm
Sit with elbows on a table, push them down and away from your ears, then turn your head up and to the right, then up and to the left, feeling a stretch on the side of your neck. This mechanically activates some vagus nerve fibers, potentially leading to a calmer state.
12. Gargling for Calm
Gargle to activate the calming aspects of the vagus nerve. When gargling, you use the back of your throat, creating vibrations that stimulate vagal pathways.
13. Probiotic & Magnesium for Mood
Consider supplementing with a quality probiotic, magnesium orotate, and coenzyme Q10. A clinical trial showed this combination could improve symptoms of major depression in the short term by supporting gut microbiome and serotonin production.
14. Rubbing Ear for Minor Calm
Gently rub behind the ear or the area right outside the ear hole with a little pressure. This activates a minor sensory branch of the vagus nerve, conveying mechanical pressure to the brainstem for a slight calming effect.
7 Key Quotes
The vagus nerve is so vast, it spreads out through so much of the body. 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, well, an entire episode of this podcast.
Andrew Huberman
The autonomic nervous system is a seesaw where the levels of alertness and calm that we experience at any one moment reflect the relative balance of sympathetic nervous system and parasympathetic nervous system activity.
Andrew Huberman
This is one of the things that I'm hoping to dispel through the course of this episode, which is this very common myth out there, it's almost pervasive that when you activate the vagus nerve, you're going to calm down. It is simply not true.
Andrew Huberman
If you want to slow your heart rate down, that is if you want to increase parasympathetic nervous system activity and you want to calm down fast, you can literally just exhales, slow your heart rate down and exhales, tilt that seesaw that is the autonomic nervous system more toward the parasympathetic side.
Andrew Huberman
The vagus nerve provides this beautiful link between the body and brain to match levels of excitation from the body to the brain and you can leverage that.
Andrew Huberman
Plasticity is a process, it's not just triggered when you go about trying to learn something, it actually takes place in sleep as well as sleep like states like non-sleep deep rest and meditation but especially in deep sleep and rapid eye movement sleep.
Andrew Huberman
The microbiota of the gut, if they're diverse and you have enough of them, are going to produce the short chain fatty acids that are critically required for the conversion of tryptophan, which again is going to come from your diet, into the serotonin of your gut.
Andrew Huberman
5 Protocols
Physiological Sigh for Rapid Calm
Andrew Huberman- Take a big inhale through the nose.
- Follow with a second, shorter, sharp inhale through the nose to maximally inflate the lungs.
- Exhale slowly and completely through the mouth until lungs are empty.
Extended Exhales for Improved HRV and Autoregulation
Andrew Huberman- Throughout the day, 10-20 times, deliberately extend your exhale.
- Focus on slowing your heart rate down during the exhale.
- Return to normal routine after each extended exhale.
Vagal Activation for Alertness and Motivation
Andrew Huberman- Engage in physical activity that involves the large muscles of your body, especially legs and trunk.
- Aim for high-intensity work or movements that cause adrenaline release.
- This will stimulate the vagus nerve, increasing brain alertness and motivation.
Neck Peri-Arterial Vagus Stretch for Calming
Andrew Huberman- Lie down or sit with hands palms down, elbows at the edge of a table.
- Push elbows down and away from your ears.
- Turn your head up and to the right, feeling a stretch on the left side of the neck.
- Repeat by turning your head up and to the left, feeling a stretch on the right side of the neck.
- Perform a few times back and forth.
Extended 'H' Humming for Deep Relaxation
Andrew Huberman- Hum by emphasizing the 'h' sound, not the 'm' (e.g., 'hhhhhh' rather than 'hmmm').
- Aim to feel the vibration move from the back of your throat down your neck into your chest and even into your belly/diaphragm.
- Perform this extended hum, which is a long, slow exhale, to induce a calming effect.