I have used the Pressurestat Model as an explanation of the craniosacral rhythm (CSR) for most of my career as a CranioSacral Therapy practitioner. Recently in my work my view of this model has changed, and as a consequence newfound awareness has developed.
The Pressurestat Model, which was created by John Upledger, DO, OMM, proposes that: 1) normal drainage of cerebrospinal fluid (CSF) out of the craniosacral system is ongoing, and 2) areas in the brain producing CSF normally do so in an on-and-off sequence, called cycles. These cycles cause a rise and fall in the total amount of CSF and pressure within the craniosacral system, brain and spinal cord. In turn, these fluid pressure changes generate the CSR. (1)
It can be helpful to periodically contemplate the models we use in our practice. The process can add greater clarity and nuance to our work, whether our thinking and research changes or re-confirms our concepts, models, or techniques.
The following questions arose for me one day: If CSF change within the craniosacral system is the primary force producing the CSR, then how much fluid per cycle is actually moving the system? Does this amount of fluid seem to be enough to create the CSR? Can a small amount of fluid within a container, such as the craniosacral system (CSS), create a large response?
When I divide the average volume of CSF produced daily, which is 650 milliliters, by the model’s average daily cycles, which are 12,960 cycles per day, I get a change in volume of approximately .05 milliliter of new CSF created per cycle, which is about 1/10th teaspoon. (2)
Is this enough fluid to move the craniosacral system, cranial bones, face, spinal column, sacrum, brain, spinal cord, and generate enough on-and-off pressure upon the motor cortex to elicit full body response?
While standing in the kitchen I measure out 1/10th teaspoon of water, place it in my palm and rock it back and forth in my hand. I feel it move, its weight and pressure upon my skin. As I do this I imagine the entire craniosacral system, brain and spinal cord being moved by this amount of fluid. Is this enough to move the craniosacral system and related structures? If not, then what else helps create the CSR?
Perhaps CSF movement is only one oscillation in a combined wave pattern consisting of many oscillations, which is created by merging of the body’s anatomical and physiological oscillations. Then the rhythmic motion we feel as the CSR could be a blend of biological frequencies. Perchance the CSR is not a separate rhythm moving the body, but is part of the body’s collective vibrations. (3)
Try this: place your hands at the thoracic inlet. Identify some of the structures in the area, such as: clavicles, sternum, upper lungs, thymus, thoracic spine, muscles, Vagus nerve, sympathetic chain, brachiocephalic veins, carotid arteries, spinal cord, dural tube, and trachea. Each one of these structures and their processes individually produces its own specific oscillation. These frequencies also unite forming an overall harmonic rhythmic pattern. What does the overall pattern feel like? What do the individual anatomical and physiological patterns feel like?
Now feel these structures and processes moving in response to another motion, the CSR. First identify the CSR, and then feel the structures moving in synchrony with the CSR. Are you feeling structure and function move in relationship to another rhythm, one that is moving them?
Is the CSR providing a fundamental pattern that is a primary organizing frequency within an individual? Is this rhythm shaping one’s existence from the micro level of particles to entire body? William Sutherland, DO, the creator of Cranial Osteopathy, proposed an elegant relationship between cerebrospinal fluid and vital forces generating life, motion and stillness within the body, which he called “The Breath of Life”. (4)
So, I began with wondering what creates the CSR and have come full circle to still not knowing. Yet, pondering the CSR has led me to feel, perceive, and use the body’s remarkable harmonic and disharmonic frequencies in new and exciting ways. Also, I have a clearer intuitive sense of what fits within my view of nature, the human body, and what I sense while working with clients.
In your opinion, what is creating the CSR? What model do you use to explain the CSR? Does your work change if your model of the CSR changes? How do you explain the CSR to your clients?
Reference List:
1. Upledger, John E., D.O., O.M.M., and Vredevoogd, Jon D., M.F.A., 1983, Craniosacral Therapy. Eastland Press, Seattle, Washington.
2. Agamanolis, Dimitri, P., M.D., et al., Neuropathology, An Illustrated Interactive Course For Medical Students and Residents. Chapter Fourteen, Cerebrospinal Fluid. Northeastern Ohio Universities College Of Medicine, http://www.neuropathologyweb.org/chapter14/chapter14CSF.html.
3. Chaitow, Leon, ND, D.O., 1999, Cranial Manipulation Theory and Practice. Churchill Livingston, London, England.
4. Sutherland, William, G., D.O., Teachings In The Science Of Osteopathy. 1990, Rudra Press.
Illustration by Tad Wanveer,LMBT, CST-D, Copyright 2008, All Rights Reserved.
