Yoga and mental health

Here are some of the mental benefits of yoga and how it produces those effects by changing the structure of your brain.

Yoga Increases Gray Matter Density

Our brains are primarily made up of two types of tissues: white and gray matter. A normal human brain consists of about 60% white matter and 40% gray matter. Both of which play important roles in healthy cognitive functioning, however, each brain tissue type has a different function:

• Gray matter consists of your brain cells or neurons. While it’s called gray matter, in reality, it is pink in color. That’s because while you’re alive, blood continuously flows through it. After you die, it turns gray. Due to its concentration of neurons, gray matter is responsible for many of your brain’s functions, including learning skills and memory. It is also responsible for the functionality of interpreting your senses of sight, hearing, smell, and touch. Additionally, it affects your muscle control and self-awareness.
• White matter, on the other hand, is the connection that extends from your brain cells. Its job is to connect different sections of your brain, much like how the internet interconnects the world, by allowing areas of your brain to send and receive signals to one another. As such, healthy white matter allows your brain to coordinate your thoughts as well as your movements.

In general, both gray and white matter complement one another to allow you to think, coordinate movement, and interpret the world surrounding you. Damage or reduction in one or the other area affects your cognitive abilities. How yoga is relevant to our brain matter is that recent research has shown that yoga increases gray matter volume in the hippocampus and frontal sections of your brain (1).

How does this help you?

Research involving a comprehensive study of structural brain scans found that a person’s general intelligence is associated with the volume of gray matter in that specific area of the brain. Essentially, the thicker the volume of the gray matter in a region of your brain, the more cells are present there, and in turn, are more likely to perform better.

A few examples include:

• London black cab taxi drivers are well reputed for their knowledge of local streets and their ability to navigate around traffic. These humans have a higher volume of gray matter in their hippocampus, which is responsible for memory and spatial navigation (2).
• Humans trained as Professional musicians, when compared to amateurs and non-musicians, present more gray matter in the Broca’s area as well as in the motor, auditory, and visuospatial regions of the brain thanks to their years of music training (3).

Similarly, in yoga, your constant use and practice of control in your postures, breathing, and mental activity results in increased gray matter density and activation in your hippocampus and prefrontal cortex. Together, allowing you to have better:

• Focus and concentration
• Emotional and impulse control
• Make you more in tune with your senses and be self-aware
• Decision making as well as being better at evaluating rewards and consequences. And, be more willing to delay gratification (4).

It Increases the Folds in Your Brain

If you look up a photo of the human brain on the internet, you’ll probably notice that its surface is made up of bumps and wrinkles, like a big sponge. These bumps play an essential role in your ability to think.

These wrinkles are basically called cortical folds, or gyrification if you prefer a more medical or scientific term. These folds contain your brain cells. And, they’re there to increase the surface area of your brain. That’s a good thing. After all, who doesn’t like more brain cells, right?

Why does your brain have folded tissue?

That’s because your brain has to fit in your head. And, because your skull is small, it has to find a way to ‘squeeze’ itself in there.

To visualise this, think of packing a small suitcase. It has only so much space. If you lay out all your clothes there, it will be hard to fit everything in. But, if you fold your clothes properly or roll them up, you’ll be able to fit more into the same small suitcase. The best part is, that folding or rolling your clothes up doesn’t change how big your shirts or pants are when you wear them. They still contain the same amount of fabric.

This uses the same concept as gyrification, the twisting and coiling of your brain tissues show up as folds. In the process, they allow more surface area, which holds more neurons, to fit in your skull.

Where does yoga fit in?

Holistic yoga consists of three main components that cater to your physical, mental, and spiritual wellbeing. These come in the form of poses (asanas), breathwork (pranayama), and meditation.

When it comes to your brain, the meditation aspect plays a large role as it is connected to increasing the number of folds in your brain (5). According to a study done by UCLA researchers, MRI brain scans showed that long-term meditators had more gyrification of their brain’s cortex. Researchers believe that this was a result of the brain’s neuroplasticity, indicating it adapted to the changes in its environment. In this particular case, it was the 20 or more years or regular meditation that produced the structural changes in the brain. Just as interestingly, the study also learned that the number of years of practice is correlated with the amount of gyrification.

Since your cerebral cortex is responsible for things like language, reasoning, perception, information processing, memory, and voluntary movement, the increase in gyrification allows for better functioning and faster information processing.

It Lets You Relax More by Reducing Stress and Anxiety

One of the primary benefits of yoga reported is a sense of post-practice relaxation. This associated body-mind connection is a positive change from the hectic pace of life but it doesn’t end there.

Yoga and Relaxation

During yoga, your brain releases all sorts of chemicals that not only help you relax but also lower your stress and anxiety levels including, gamma-aminobutyric acid (GABA), dopamine, oxytocin, serotonin, and endorphins. Each of which functions in its own way to help you calm down and feel better.

• GABA is a neurotransmitter or your brain’s chemical messenger. Its job is to suppress neural activity in order to prevent your brain from getting overly excited. In doing so, it controls how much fear, stress, anxiety or nervousness you’ll feel. Research shows that yoga increases your GABA levels by 27% (6). In fact, another study found that yoga is even better than walking if you want to relax and reduce anxiety (7).
• Happiness Hormones. Collectively, your happiness hormones are dopamine, oxytocin, serotonin, and endorphins. They’re called as such because each of them makes you feel better about yourself and your well-being. For example, dopamine makes you feel rewarded and lets you experience a pleasure. Meanwhile, serotonin reduces tension to help relieve stress and anxiety.

Together, these chemicals help you relax and feel content. It is why many yogis will tell you that they feel happier after a class.

Yoga and Stress Reduction

One of the reasons you’re able to relax is that yoga also does a number on your stress response (8). During a yoga session, certain parts of your brain slow down to allow them to rest. This functionality helps you de-stress, which takes place in two major areas of the brain:

• Frontal lobe. The frontal lobe is the most advanced part of your brain because it is responsible for most of the thinking, planning, and reasoning. Additionally, it plays a role in self-awareness and emotional regulation. As you can imagine, this part of the brain is racing when you encounter a dilemma or when you feel self-conscious about something. However, during yoga, your frontal lobe goes on vacation. Thus, allowing you to take a break for a while.
• Parietal lobe. This section of the brain handles all the information coming from your senses. It takes in the sights, sounds, and everything else you observe around you. As such, when you’re always on the move, working, driving, or observing things, you can imagine how much activity is going on here. Yoga likewise causes your parietal lobe to slow down.

But, it doesn’t stop there. Yoga also helps reduce stress by lowering your body’s cortisol and adrenaline levels, two critical stress hormones. That is, when you feel stressed or anticipate something stressful about to happen, your stress response is triggered. As a result, your body releases stress hormones to help you become more alert, make your heart beat faster, and spike your blood pressure. All of these are a result of your body getting flooded by stress hormones including cortisol and adrenaline.

Stress in itself is a good thing. It allows us to take on emergencies or focus better when we need to take a test or give a presentation. It, likewise, prepares you to protect yourself during life-threatening events.

But, if you have a hectic lifestyle and are constantly stressed, it can become harmful to your health. This is because your stress hormones trigger different events in your body to produce the effects mentioned earlier. Among them are releasing more sugar into your bloodstream, increasing your blood pressure, and producing inflammation. When sustained for long periods of time, this can result in serious conditions like heart disease, high blood pressure, and diabetes.

In contrast, yoga helps to reverse these effects. One study notes how yoga reduces your body’s cortisol levels (9). Meanwhile, another study found that 12 minutes of daily yoga helps lower your body’s inflammation response, which is important as chronic inflammation is linked to serious long-term conditions like depression and heart disease (10).

Yoga and Anxiety

Anxiety is closely related to stress. But, they aren’t the same thing. Stress is the response your body produces due to a threat. Once that situation passes, the stress goes away. On the other hand, anxiety can be a result of stress as well as a myriad of other factors (to name a few: trauma, brain chemistry, environmental influences, genetics, use or withdrawal from substances, etc.)

Common symptoms of anxiety may include constant worry, feeling restless, startling easily, inability to focus, and often difficulties sleeping.

Here’s where yoga comes in.

Interestingly enough, while yoga increases the volume of gray matter in some areas of the brain, it also has an opposite effect on other regions of the brain. One such example is your brain’s amygdala (11). The amygdala is what you can call the message processing center of your brain. It receives incoming messages from your senses and internal organs and then processes them. As such, it plays a critical role in your emotions and how you react to them, the most prominent of these emotions being fear. This is why you get nervous or afraid when you feel an impending threat or problem.

Thanks to yoga, the reduction of gray matter in your amygdala means that there is less activity in this part of your brain. As such, you’re better at handling fear and your emotions. Plus, you’re likewise better able to relax.

Final Thoughts

Yoga is commonly thought of as a series of poses that involve stretching and other complex movements. As such, its benefits are often believed to be physical. However, its effects have much more depth. The combination of poses, breathing, and meditation produces structural changes in your brain. This not only causes certain areas of your brain to increase or decrease in size but also affects your cognition as well as how you process your emotions, stress, and anxiety. All of which help you live a happier, healthier life.

References:

(1) io9.com/how-meditation-changes-your-brain-and-makes-you-feel-b-470030863
(2) scientificamerican.com/article/london-taxi-memory
(3) nyaspubs.onlinelibrary.wiley.com/doi/abs/10.1196/annals.1284.062?sid=nlm%3Apubmed
(4) jacobspublishers.com/effects-of-long-term-yoga-practice-breathing-and-meditation-on-cognitive-function-and-emotional-control-a-review-of-the-literature/
(5) ncbi.nlm.nih.gov/pmc/articles/PMC3289949/
(6) ncbi.nlm.nih.gov/pubmed/17532734
(7) ncbi.nlm.nih.gov/pubmed/20722471
(8) sigmapubs.onlinelibrary.wiley.com/doi/pdf/10.1111/wvn.12097
(9) ncbi.nlm.nih.gov/pmc/articles/PMC3768222/
(10) newsroom.ucla.edu/releases/yoga-reduces-stress-now-it-s-known-236785
(11) link.springer.com/article/10.1007/s11682-018-9826-z