Phase 2 – The rhythmic fluctuation of the cerebrospinal fluid

As discussed in the previous submission, The Brain and Spinal Cord or CNS, expand and contract at a rate of 8-12 cycles per minute.  This expansion and retraction is one of the causes of Cerebrospinal Fluid (CSF) fluctuation.
As the brain and spinal cord change shape and go through their cycle of inhalation and exhalation, the CSF fluctuates back and forth in the spaces in the brain and spinal cord.  Because of a large membrane surrounding the brain and spinal cord called the Dura, The cerebrospinal fluid (CSF) fluctuates, or moves back and forth in a relatively closed container.

Since the Dural membrane follows the nerves out of the spine, the small excess travels out along the channels around these nerves during primary respiration.

The CSF has important functions in circulation and nourishment of body tissues.

Fluid Exchange is vital to normal physiology. All the processes of life occur because fluids flow: Through channels, across membranes, and within open spaces. Should the flow of fluids stagnate, all of life becomes diminished… and health is compromised.
Cerebro-Spinal Fluid (CSF) surrounds our brain and spinal cord. A mere 140 ml of fluid bathes the brain and fills the ventricles (internal cavities of the brain).

This Cerebro-Spinal Fluid replenishes itself 3-4 times each day. Once thought only to provide buoyancy, CSF has now been discovered to provide important nutrient functions. Not only are essential substances made available, but harmful substances are cleared away. CSF establishes a stable and specialized fluid environment for nerve cells.

There are no lymphatic vessels within the Central Nervous System. The brain and spinal cord are instead cleaned by the rapid creation and absorption of the Cerebro-Spinal Fluid. This circulation of CSF was once thought be a “closed” system. To speak of movement of CSF outside of the brain into the “periphery” was considered heresy. Recent studies, however, now reveal that CSF is in direct communication with the lymphatic system of the rest of the body.

One of Dr. Sutherland’s main contributions was the discovery of the fluctuant nature of Cerebro-Spinal Fluid. The CSF is not simply circulating. The CSF fluctuates. Fluctuation is defined in Websters dictionary as: “The motion of a Fluid contained within a natural or artificial cavity, observed by palpation or percussion.”

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Jason Brandow,
Craniosacral Therapist, Osteopathy Student.