Now that we’ve talked a bit about rhythm and regulation, and gotten oriented to the embracing field of gravity, let’s bring our attention to the breath. If life is an ember, the ember that yet burns (N Kasea in Tzutuj’il Mayan), breath is the wind that fans the flames. This is an observation, almost pedestrian in its obviousness, and yet it is true. The breath delivers, to each cell in the body, the wind that fans the flames in the form of oxygen that combusts in the cellular furnace. It also removes the accumulation of built-up gases, the carbon dioxide that we do not need, aggregates it, and expels it from the body with the exhalation.
You breathe in new life, you breath out waste. Breathing, is, in its primary manifestation therefore a mechanism of gas exchange. It tends the metabolic fire of life. And yet even this, though true, barely touches into the deep mystery of the breath.
If we approach it with humility, then bring an autonomic lens, we must wonder at this mechanism that sits at the intersection of the conscious and the automatic. Your breath will breathe you whether you remember it or not, yet what other autonomic phenomenon can you so directly modulate with awareness? The heart, while meditation masters have learned to steer it after prodigious feats of concentration, is not so easy to speed up or slow down intentionally. Yet even a small child can change the rhythm and depth of their breath. They can hold it when they jump in the pool. They can lengthen it when they blow out a candle, make it deeper by exaggerating the rise and fall of the belly. It is a mechanism through which we can regulate or dys-regulate ourselves on purpose or accidentally. And all of us know, whether we have done this by choice or had it happen to us, how deeply the breath governs the feeling of being in our bodies. Whether it is discovering the relief that comes from a deep breath, or accidentally moving ourselves into panic by breathing too shallowly, if we are wearing a body we learn at a young age that breathing is central to how it feels to be in the skin we are wearing. We learn this whether we develop any sense of how to work intentionally with the breath or not, but keep in mind that if you did not already have exquisite breath control you could not talk.
The neural architecture of the rhythm of the breath is regulated, deep within the brainstem, in areas that govern pattern generation in the body. The brainstem, as we have been learning, is considered the basement of the brain, the oldest deepest structures. The brain develops from the bottom to the top, from the back to the front, and these areas are some of the earliest to form embryonically, because their functioning is so deep and critical to all higher processes. These clusters of inter-neurons, that link together various aspects of the Autonomic Physiology, govern the central rhythms, the oscillations of our fundamental being. These patterns generators are, technically, “neuronal circuits that when activated can produce rhythmic motor patterns such as walking, breathing, flying, and swimming in the absence of sensory or descending inputs that carry specific timing information.” (Eve Marder 2001).
The final clause of this sentence is crucial because it suggests that these pattern generators can operate based on their own intrinsic timing. They don’t require a down-coming directive from higher in the brain. That duly noted, the body’s rhythmic pattern generators can be influenced by four factors:
their intrinsic organization
fibers descending from higher brain centers
sensory information incoming (fibers coming up from the body)
chemical messengers such as hormones and neurotransmitters
At the heart of the Breathing Pattern Generator, deep in the medulla oblongata of the brainstem, is a cluster of about 10,000 interneurons called the Pre-Bötzinger Complex (PreBötc). Interestingly, and non-accidentally, in mammals this complex is located in a part of the medulla adjacent to the ventral vagal source nucleii in the Nucleus Ambiguus. See the two circles in the diagram below. The NA in the diagram, which you are viewing at right below in transverse section, is basically sitting on the PreBötc’s shoulder.
This is, among my colleagues, many of whom are quite learned in this area, something of a revelation. Yet this makes sense very deeply because the NA in the brainstem is the nucleii that assembles the ventral vagal complex, or social engagement system. This is the system that unites the neural regulation of the face, voice, tuning of the middle ear, larnyx, and pharynx, and turning of the head and neck with the heart and breath in the presence of an attuned caregiver.
Keep reading with a 7-day free trial
Subscribe to The Neurobiology of Connection to keep reading this post and get 7 days of free access to the full post archives.