I had intended to get this blog post finished before Christmas, but that was so 2014. So I’ll just leave it back there in the past and get cracking again here in the New Year.
I have been breaking down an article which lays out a theoretical model of the neuroscience of yoga and self-regulation. It’s such a groundbreaking article that it deserves lots of blogging!
My first blog was an intro to the intersection of yoga and neuroscientific research. If you haven’t read it yet, you may want to catch up here. The second blog explained the idea of top down processing. The third part looked at bottom up processing.
This fourth blog is about how the researchers understand the top-down/bottom-up feedback loop and how they have created their working model from it.
You may have a friend or teacher with a sincere personal yoga practice, who seems to be, for the most part, pretty chill. Not that yoga people don’t still have their share of issues – we all know the stories (insert appropriate eye roll here). But if I can step out on a shaky limb and make a generalization, many people who have been practicing yoga for a while seem to be able to cope fairly well.
I remember when I met my first meditation teacher. I kept thinking, “How can she be so chill? I wanna be like that.” After practicing for a while I became less reactive (at least about a few things in my broad spectrum of freakoutable, vata-deranged drama). Maybe you’ve noticed it – that your practice has helped you to deal with life a little more gracefully, or at least more easily than before you started practicing. In my case, I was able to let go of some of those more culturally tried-and-true inhibitory tools like cigarettes and alcohol. (Admittedly peri-menopause makes me do shots of Vitex tincture and cling to packs of pranayama, but I left the external toxins in the dust long ago.)
My guess is that the article’s authors noticed the “yoga chill” and wanted to dig into the neurobiologic how of the process. So their theory is that with continued practice, this top-down, bottom-up, bi-directional processing creates loops of feedback and information that make you more mental-emotionally stable and functional. Your body is stronger, your nervous system works better, your brain functions better, your cardiovascular systems improves, etc.
Gard and his team theorize that, in terms of dealing with stress, regular yoga practice affects four primary factors.
I mentioned this perception function in the previous post. Interoception is the mechanism through which we become aware of what’s going on in our bodies. It’s about feeling – and feeling happens in the body. Trauma and other difficult life situations can cut us off from the feelings in our bodies. When we don’t know how we feel, we don’t know how to respond. When we don’t know how to respond, we tend to get anxious. And then we just feel miserable and worried all the time. So yoga helps us to develop an ability to more objectively feel what we are feeling.
…or “more efficient bidirectional feedback.” This second factor basically means that the front brain gets better feedback from the body and can make better decisions about what to think or do based on that accurate feedback. If you have a less reactive amygdala, and a better toned vagus nerve, you are less likely to misperceive a stick as a snake. You’ll see it as a stick. For most people, most of the time, life is full of sticks, there aren’t that many snakes. But if you’ve seen a lot of snakes in your life, you may think that your path is full of them. Doing yoga seems to help with something called “extinction learning.” In other words you learn to unlearn that all sticks should be perceived as snakes. You start to see that often, sticks are just sticks – they pose no real threat.
…which goes along with the above two factors. If you are able to remember that mostly you will be encountering sticks, not snakes on your life’s journey, then your front brain and hippocampus can inhibit the amygdala – that little part of your brain that wants you to scream whenever you see anything remotely resembling a snake. When you can do this easily, it puts less stress on your heart, reduces muscular tension and pain, and also decreases systemic inflammation. It’s a really good thing to be able to inhibit your inner freak when it is freaking out unnecessarily. Which leads to…
- Improved Prediction and Error Correction
This is related to all of the above factors as well. It’s an integrative function. Yoga helps you to become better at objectively assessing situations, thinking about them clearly, feeling them clearly, and then making better decisions about how to act in any situation. You are better able to predict what is going to happen as well and better able to adjust when you’ve made a mistake.
So top-down, bottom-up and the integration of the two – that’s basically what Gard’s model spells out. I hope these blogs have helped you to understand these concepts better.
One question I’m leaving with is what about left-right integration? For example the left and right hippocampi serve different functions in terms of memory and appraisal. I’d like to see the authors include any research on how yoga helps integrate left/right functions (I’m thinking things like nadi-shodhana as well as asymmetrical asanas) in a subsequent refinement of their current model.
In the next few blogs I’m going to get into Gard’s theories of how the specific practices – ethics, pranayama, asanas and meditation – affect our neurobiology. Fun, fun, fun!