Neurobiology of Asana
You know that feeling after yoga class? That one where you just feel really, really good? You’re relaxed, not troubled, and in that moment everything is all right, if not verging on miraculous? That is what I wanted to understand. What does a great asana practice do to our brains that can shift our perspective, sometimes radically, in such a short amount of time?
It turns out that yoga asana makes real changes to our neurology: in the short-term, shifting which areas of the brain are active and which are passive and adjusting our neurotransmitters so we have less stress and more feel good and mellow, and in the long-term, creating structural changes that increase clarity and joy.
The postural forms of yoga that have been studied for their neurological benefits are mostly Iyengar and Kripalu in the U.S. and traditional Hatha Yoga in India. So, slow yoga. What I’m about to cover may or may not apply to other forms, like vinyasa flow or hot yoga. We just don’t know.
What we do know is that slow yoga, the type that starts with pranayama (breathing exercises), ends with savasana, and holds postures for several breaths in between, has most of the benefits of both meditation and exercise, plus a few that are all its own. Keep in mind, slow does not mean easy. The approach may be gentle but the practice can be intense.
Since the neurobiological benefits of meditation have been covered, in this entry I will look at the similarities and differences in the neurological effects of exercise and postural yoga, and at how the benefits of postural yoga (a.k.a. asana practice) differ from those of exercise and meditation.
How Asana Affects the Brain
The first thing to know is that when a part of the brain experiences increased activity, neurons build stronger connections in their communication circuits. This type of change to brain structures is called neuroplasticity. This is how we learn, how we modify behavior, and how we improve our cognitive abilities.
Motoring
When we exercise, there is increased activity in all the areas related to movement: the brain stem, cerebellum, basal ganglia, and parietal cortex are all called on. The more attention we pay to our actions, the more parts of our brains we engage and the more connections our brains form.
Brain stem: When we consciously sit and stand upright, we call on the reticular formation in the brain stem to tell the brain it’s time to be alert. The reticular formation plays a role in our sleep-wake cycle. This may be a contributing factor in postural yoga’s positive effect on sleep quality.
Cerebellum: This is the wrinkled looking ball at the base of the brain. It plays a huge part in motor control and contains more than half of all the neurons in the brain. Precise movement is not innate; it is learned through trial and error in the cerebellum. The mindful alignment details of asana strongly engage the cerebellum, making deliberate movement more natural.
Basal ganglia: Located just outside the limbic system, the basal ganglia are concerned with action selection. They send inhibitory signals to all the parts of the brain that can generate movement, and when appropriate, they release this inhibition and let actions happen. The mindful movements of yoga postures activate the basal ganglia even more than the rapid-fire actions of aerobic exercise or the persistent inhibition of movement in most styles of meditation.
Parietal cortex: One of the jobs of the parietal lobes is to integrate sensory information, including touch, pressure, and pain. It is how we know where we are in space. It is also important in creating our sense of self as separate from the rest of the world. The parietal cortex is also responsible for limb movement. It plays an important part in directing the body into and out of asana.
New Neurons
Some parts of the brain don’t just form stronger connections under the influence of exercise and asana, they actually grow new neurons. This is because exercise and asana produce brain-derived neurotrophic factor (BDNF) and other chemicals that spawn the growth of new neurons in the prefrontal cortex, hippocampus, anterior cingulate cortex, parietal cortex, and cerebellum.
Meditation also encourages growth in all of these areas except the cerebellum. In fact, long-term meditators have significantly thicker prefrontal cortices than the general population.
Growth in the prefrontal and anterior cingulate cortices explains the relationship between exercise, including postural yoga, and faster cognitive function; increased cognitive flexibility and multi-tasking; better attention control and attention span; increased impulse control; better spatial and declarative memory; and increased working memory updating and capacity.
That last bit also relates to the hippocampus, since it is the memory librarian. Working memory refers to what you’re thinking about at any given moment. Some researchers call it our mental chalkboard. Working memory happens in the cortex. But memory updating, i.e., pulling relevant information out of long term storage, is the job of the hippocampus. Increased working memory capacity is the ability to hold more information in mind while seeing how it all fits together.
One area that sees decreased activity in asana practice (and in meditation) but not in other forms of exercise is the amygdala, which is the emotional center responsible for triggering the fight or flight alarm. This is a very good thing. The amygdala is the “emotional hijacker,” to borrow Daniel Goleman’s phrase. When it kicks in, we experience fear or rage. The amygdala has been found to shrink in people with long-term asana and meditation practices.
Neurotransmitters
Neurotransmitters are the chemicals that neurons pass to one another to transmit messages. Exercise, asana, and meditation all boost serotonin, a well-known neurotransmitter related to feelings of happiness and well-being. All three activities also encourage the brain to produce more melatonin, which facilitates our sleep-wake cycles.
Exercise famously produces neurotransmitters known as euphoriants. Specifically, exercise encourages the release of phenethylamine (a stimulant), endorphins (opioids), and anandamide (a cannabinoid). Asana only releases the second two—the opioids and cannabinoid, not the stimulant. And if you’ve done even one asana practice, this makes perfect sense.
Where the postural practice of yoga really stands out as far as neurotransmitters are concerned is in the production of gamma-aminobutyric acid (GABA). Asana has been shown to increase the presence of this neurotransmitter by a lot; one study showed an average increase of 27 percent. GABA inhibits stressful, negative thoughts and is associated with improved mood and decreased anxiety. Alcohol and tranquilizers work by attaching to GABA receptors. The reason for this flood of GABA is likely due to how strongly asana engages the basal ganglia. The basal ganglia run on GABA. Activating the basal ganglia through conscious, specific movements evidently releases tons of the stuff.
Another difference between exercise and yoga is their effect on cortisol, which is not a neurotransmitter but a hormone produced in response to stress. While we exercise, cortisol production is stimulated; however, exercise does not result in lasting increases to cortisol levels and is related to better stress management. Asana and meditation both just flat out reduce the amount of cortisol in our systems. Even just one yoga class will bring cortisol levels down a significant amount.
Moksha, a.k.a. Spiritual Liberation
The purpose of all yoga is enlightenment, and the goal of Hatha Yoga is living spiritual liberation. The postural practice of yoga is phenomenally beneficial to the brain. By integrating moving and mindfulness, we are integrating our brains from the center to the surface and from side to side. The result is stronger network integration and greater mental efficiency. Yoga brains are more resilient in the face of stress and age and show greater fluid intelligence, which is the ability to think abstractly, to identify patterns and discern relationships, and to solve problems.
But slow yoga can’t replace aerobic exercise (or probably faster forms of yoga) when it comes to cardiopulmonary benefits. And it can’t replace sitting quietly in meditation when it comes to detaching from your sense of self and finding union with the Absolute.
On the road to enlightenment, asana will get us far. But if we want to take our yoga all the way, at some point we have to sit down and be still.
It turns out that yoga asana makes real changes to our neurology: in the short-term, shifting which areas of the brain are active and which are passive and adjusting our neurotransmitters so we have less stress and more feel good and mellow, and in the long-term, creating structural changes that increase clarity and joy.
The postural forms of yoga that have been studied for their neurological benefits are mostly Iyengar and Kripalu in the U.S. and traditional Hatha Yoga in India. So, slow yoga. What I’m about to cover may or may not apply to other forms, like vinyasa flow or hot yoga. We just don’t know.
What we do know is that slow yoga, the type that starts with pranayama (breathing exercises), ends with savasana, and holds postures for several breaths in between, has most of the benefits of both meditation and exercise, plus a few that are all its own. Keep in mind, slow does not mean easy. The approach may be gentle but the practice can be intense.
Since the neurobiological benefits of meditation have been covered, in this entry I will look at the similarities and differences in the neurological effects of exercise and postural yoga, and at how the benefits of postural yoga (a.k.a. asana practice) differ from those of exercise and meditation.
How Asana Affects the Brain
The first thing to know is that when a part of the brain experiences increased activity, neurons build stronger connections in their communication circuits. This type of change to brain structures is called neuroplasticity. This is how we learn, how we modify behavior, and how we improve our cognitive abilities.
Motoring
When we exercise, there is increased activity in all the areas related to movement: the brain stem, cerebellum, basal ganglia, and parietal cortex are all called on. The more attention we pay to our actions, the more parts of our brains we engage and the more connections our brains form.
Brain stem: When we consciously sit and stand upright, we call on the reticular formation in the brain stem to tell the brain it’s time to be alert. The reticular formation plays a role in our sleep-wake cycle. This may be a contributing factor in postural yoga’s positive effect on sleep quality.
Cerebellum: This is the wrinkled looking ball at the base of the brain. It plays a huge part in motor control and contains more than half of all the neurons in the brain. Precise movement is not innate; it is learned through trial and error in the cerebellum. The mindful alignment details of asana strongly engage the cerebellum, making deliberate movement more natural.
Basal ganglia: Located just outside the limbic system, the basal ganglia are concerned with action selection. They send inhibitory signals to all the parts of the brain that can generate movement, and when appropriate, they release this inhibition and let actions happen. The mindful movements of yoga postures activate the basal ganglia even more than the rapid-fire actions of aerobic exercise or the persistent inhibition of movement in most styles of meditation.
Parietal cortex: One of the jobs of the parietal lobes is to integrate sensory information, including touch, pressure, and pain. It is how we know where we are in space. It is also important in creating our sense of self as separate from the rest of the world. The parietal cortex is also responsible for limb movement. It plays an important part in directing the body into and out of asana.
New Neurons
Some parts of the brain don’t just form stronger connections under the influence of exercise and asana, they actually grow new neurons. This is because exercise and asana produce brain-derived neurotrophic factor (BDNF) and other chemicals that spawn the growth of new neurons in the prefrontal cortex, hippocampus, anterior cingulate cortex, parietal cortex, and cerebellum.
Meditation also encourages growth in all of these areas except the cerebellum. In fact, long-term meditators have significantly thicker prefrontal cortices than the general population.
Growth in the prefrontal and anterior cingulate cortices explains the relationship between exercise, including postural yoga, and faster cognitive function; increased cognitive flexibility and multi-tasking; better attention control and attention span; increased impulse control; better spatial and declarative memory; and increased working memory updating and capacity.
That last bit also relates to the hippocampus, since it is the memory librarian. Working memory refers to what you’re thinking about at any given moment. Some researchers call it our mental chalkboard. Working memory happens in the cortex. But memory updating, i.e., pulling relevant information out of long term storage, is the job of the hippocampus. Increased working memory capacity is the ability to hold more information in mind while seeing how it all fits together.
One area that sees decreased activity in asana practice (and in meditation) but not in other forms of exercise is the amygdala, which is the emotional center responsible for triggering the fight or flight alarm. This is a very good thing. The amygdala is the “emotional hijacker,” to borrow Daniel Goleman’s phrase. When it kicks in, we experience fear or rage. The amygdala has been found to shrink in people with long-term asana and meditation practices.
Neurotransmitters
Neurotransmitters are the chemicals that neurons pass to one another to transmit messages. Exercise, asana, and meditation all boost serotonin, a well-known neurotransmitter related to feelings of happiness and well-being. All three activities also encourage the brain to produce more melatonin, which facilitates our sleep-wake cycles.
Exercise famously produces neurotransmitters known as euphoriants. Specifically, exercise encourages the release of phenethylamine (a stimulant), endorphins (opioids), and anandamide (a cannabinoid). Asana only releases the second two—the opioids and cannabinoid, not the stimulant. And if you’ve done even one asana practice, this makes perfect sense.
Where the postural practice of yoga really stands out as far as neurotransmitters are concerned is in the production of gamma-aminobutyric acid (GABA). Asana has been shown to increase the presence of this neurotransmitter by a lot; one study showed an average increase of 27 percent. GABA inhibits stressful, negative thoughts and is associated with improved mood and decreased anxiety. Alcohol and tranquilizers work by attaching to GABA receptors. The reason for this flood of GABA is likely due to how strongly asana engages the basal ganglia. The basal ganglia run on GABA. Activating the basal ganglia through conscious, specific movements evidently releases tons of the stuff.
Another difference between exercise and yoga is their effect on cortisol, which is not a neurotransmitter but a hormone produced in response to stress. While we exercise, cortisol production is stimulated; however, exercise does not result in lasting increases to cortisol levels and is related to better stress management. Asana and meditation both just flat out reduce the amount of cortisol in our systems. Even just one yoga class will bring cortisol levels down a significant amount.
Moksha, a.k.a. Spiritual Liberation
The purpose of all yoga is enlightenment, and the goal of Hatha Yoga is living spiritual liberation. The postural practice of yoga is phenomenally beneficial to the brain. By integrating moving and mindfulness, we are integrating our brains from the center to the surface and from side to side. The result is stronger network integration and greater mental efficiency. Yoga brains are more resilient in the face of stress and age and show greater fluid intelligence, which is the ability to think abstractly, to identify patterns and discern relationships, and to solve problems.
But slow yoga can’t replace aerobic exercise (or probably faster forms of yoga) when it comes to cardiopulmonary benefits. And it can’t replace sitting quietly in meditation when it comes to detaching from your sense of self and finding union with the Absolute.
On the road to enlightenment, asana will get us far. But if we want to take our yoga all the way, at some point we have to sit down and be still.
Main Sources
Gard T, Taquet M, Dixit R, Hölzel BK, de Montjoye Y-A, Brach N, Salat DH, Dickerson BC, Gray JR and Lazar SW. “Fluid Intelligence and Brain Functional Organization in Aging Yoga and Meditation Practitioners.” Frontiers in Aging Neuroscience. 6. 76 (2014). Web.
Hanson, Rick. Buddha’s Brain: the Practical Neuroscience of Happiness, Love and Wisdom. Oakland, CA: New Harbinger, 2009. E-book.
Khalsa, Sat Bir Singh & Julie Gould. Your Brain on Yoga. New York: RosettaBooks, 2012. E-book.
Kramer, Benjamin. Meditation and the Brain: how modern science is proving two thousand year old wisdom. 2014. E-book.
Newberg, Andrew & Mark Robert Waldman. How God Changes Your Brain: Breakthrough Findings from a Leading Neuroscientist. New York: Ballantine Books, 2009.
Streeter, Chris S., Theodore H. Whitfield, Liz Owen, Tasha Rein, Surya K. Karri, Aleksandra Yakhkind, Ruth Perlmutter, Andrew Prescot, Perry F. Renshaw, Domenic A. Ciraulo, and J. Eric Jensen. “Effects of Yoga Versus Walking on Mood, Anxiety, and Brain GABA Levels: A Randomized Controlled MRS Study.” The Journal of Alternative and Complementary Medicine. 16. 11 (2010). Web.