Perhaps it is the climate of our nation, but I am overdue for a geek blog. If the words “gray matter” intrigue or excite you, or if you just wonder why savasana feels so good, please enjoy this blog on how yoga can embody your nervous system.
Gray matter is brain tissue located in the cerebral cortex of the brain. Studies have shown (you are going to have to look them up on your own) that there is a decrease in grey matter in individuals with chronic pain. It is a downward spiral: decrease in grey matter can lead to memory loss, decreased motor response and emotional problems like anxiety and depression. But guess what? Yoga can increase grey matter! The process requires that we get out of our head and give our brain “feel feedback” from the rest of the body.
Central Nervous System
To understand the importance of how yoga helps to mentally connect us to our physical body, you need to have a basic nerd understanding of the Nervous System. The brain thrives on stimulation; it is what allows the continual growth and repurposing of neurons, the specialized cells of the Central Nervous System (CNS). As babies, we have to learn to move the arms and legs with sensory motor awareness from the brain and spine – the CNS. More specifically, the motor cortex of the brain sends impulses from the neurons to the muscles. The motor cortex is a chunk of the cerebral cortex (yep, back to gray matter), that is involved in control and dishing out orders to the muscles to create movement. Most of us don’t remember having to think to learn to crawl, but it was difficult stuff. With repetition, movements like walking become effortless.
Like a baby first learning to crawl, trauma, chronic pain and disease can make us work to make what were once conditioned reflex movements happen. Sometimes we are able to make those movements, but don’t realize that muscles that once turned on automatically are in a permanent state of savasana and other muscles are pulling 70 hour work weeks. Depending on previous physical and/or emotional trauma, we can experience diverse loss of sensory motor awareness (coined Sensory Motor Amnesia by Thomas Hanna). This is no longer a response to the actual damage. It is a learned habitual behavior by the brain. These habits can only be permanently changed by relearning sense of movement through movement- the big word – neuroplasticity – and it takes the disciplined, captivated mind of a yogi!
The Roll of Trauma
If the nervous system never experienced physical or emotional trauma, the benefits of yoga would rest solely on who wears the best pants. In a healthy adult, the brain and spinal chord respond to conscious thought by sending nerve impulses from the senses and the Central Nervous System to the Peripheral Nervous System (PNS – the nerve fibers that branch out from the spinal chord to all parts of the body that receive and send messages to the brain). The CNS also sends hormones and chemicals through the organs and the rest of the body. Think of the CNS as driving on the nerve expressway and the PNS as getting off to take a local, more distant route; it is two way traffic. In individuals who have disconnected from their bodies for numerous reasons, nervous system response time can be slow, like driving the Kennedy into Chicago at 5pm on a Friday.
Peripheral Nervous System
The Peripheral Nervous System is divided into the Autonomic Nervous System (ANS – stuff just happens, ignore it and you don’t need to do a darn thing) and the Somatic Nervous System (voluntary “I got this” system). The ANS is mainly responsible for involuntary responses such as heart rate, digestion and breathing. This system is no buttercup and will do its job without coddling, but yoga recognized the ability to positively influence the ANS through asana, pranayama, meditation and thought patterns. The ANS is famous for hosting our good twin and evil twin, Parasympathetic and Sympathetic; except nether of them are actually evil, unless they are getting all the attention all the time. The sympathetic throws tantrums on a diet of STRESS and the parasympathetic thrives on RELAXATION. When the sympathetic is acting out, it hangs out with troubled kids like Amygdala, who feeds fear to our brain. In this overstimulated, noisy, multitasking, ever present electronic-devices world, our ANS often needs a timeout – a safe space to overindulge the peaceful parasympathetic. The Eight Limbs of Yoga are structured to deepen our sensory withdrawal from all the external rubbish (pratyhara – the 5th limb) and nurture the parasympathetic or Relaxation Response (as termed by Dr. Herbert Benson in his 1975 book). Encouraging the sense to go internal can be as simple as watching the breath breathe (pranayama – the 4th limb of yoga), or it can be more systematic. In a yoga practice that includes postures (asana – the 3rd limb of yoga), we bring awareness to the muscles, bones and breath.
How The Koshas Fit In
The Maya Kosha model of yoga teaches that we are multi-layered beings. Our first layer is the Annamaya Kosha; our outermost physical body. We may dress it up and look at it in the mirror but this layer where our muscles and bones live needs to feel like part of something bigger inside of us. When we do formal techniques in yoga like progressive muscle relaxation, the mind and body both benefit. The overlying goal in squeezing specific muscles then releasing them is to see where tension is held in the Annamaya Kosha. The body/brain relationship goes on a date to Cognitive Connection where they dine on skeletal muscles and sensory organs…the Somatic System gets a romantic interlude! Additionally, when we do yoga postures, the Somatic System provides voluntary control of the body movements and tells the brain the position of the body in space through specific nerves called proprioceptors. Normally, the voluntary activities of the Somatic System happen effortlessly below the level of conscious awareness. Unfortunately, somatic signals don’t come to us in the form of words. When we are able to experience them, they are felt as bodily sensations. Yoga strengthens this conscious feeling based interfacing from the brain to the periphery of the body. Incoming (sensory) and outgoing (motor) messages change lanes freely between the CNS and the organs, muscles and glands. The expressway and local routes are wide open!
If you read this far, here is your bone: There is no need to re-read this or study the nervous system. Embody means “to embrace, to give a concrete form to, to provide with a body”. Yes, simply provide your brain and nervous system with your body! It also doesn’t matter why you come to yoga, what style of yoga you choose, or if you can stand on your head. When you are on your mat and feeling yourself, your grey matter is having a party in your brain!!! As long as you stick with your practice, the party can get bigger and will never run out of cake.
Namaste, Megan
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