The Jugular Foramen: The Cradle of Autonomic Stability

By Dale G. Alexander, LMT, MA, PhD
July 12, 2017

The Jugular Foramen: The Cradle of Autonomic Stability

By Dale G. Alexander, LMT, MA, PhD
July 12, 2017

The jugular foramen is one of the most important passageways in the human skull. This pair of openings is located in the base of the cranium. They are framed by the temporal and occipital bones and are usually described as being divided into two parts, an anteromedial compartment and a posterolateral one. Wikipedia suggests that the foramen is larger on the right than on the left, while Radiopaedia suggests the size of these openings is remarkably variable and asymmetrical.1-3

What passes through these openings in the smaller and more anterior portion are venous drainage from the brain and the glossopharyngeal cranial nerves. And in the larger posterior portion passes additional venous drainage, the ascending pharyngeal artery, and two additional cranial nerves — the vagal and spinal accessory nerves. For an anatomical analogy, imagine the cross-section of a thick electrical cable containing multiple wires.1-3

The first takeaway is that the two jugular foramen very often become compressed and thus the function of the vessels and nerves that pass through these openings may become reduced or distorted. Veins respond to compression here by congesting their fluids, while the nerves' ability to send, receive and accurately interpret sensory information may result in under- or over-reactive responses.4-5

The Foramen Compressed

Simple examples to heighten your awareness of just how often you have already dealt with this compression include: tight trapezius and varying levels of spasm of the SCM muscles which are governed by the spinal accessory nerves; swallowing difficulties governed by the glossopharyngeal nerves; and a host of heart and GI disorders that relate back to the ability of the vagus nerve network to act as a bio-informational data bus that routes its impulses in both afferent and efferent directions.5

There is an endless list of possible contributing factors to how compression of these passageways may occur: head trauma, whiplash-like events, extensive dental procedures, and chronic stress are likely near the top of the many categories.

One obvious implication of compression within these openings is its relationship to chronic headache patterns either because of decreased venous drainage from the brain or impeded arterial flow to the brain and upper throat.

John E. Upledger DO, the developer of CranioSacral Therapy, asserted in his teachings that 85 percent of the brain's venous drainage flowed through the bilateral openings of the jugular foramen.6 In my clinical experience, congestion is the inevitable sequela to compression in all parts of the human body.4

The second takeaway I am encouraging is that if someone shows up on your table with any kind of "chronic somatic dysfunction or pain," you can be fairly certain that there is compression and congestion associated with their jugular foramen.

As these influences have already led to imbalances of coordinated communication and function within the three divisions of the autonomic nervous system — the sympathetic and parasympathetic, and enteric. This is because the vagal nerves serve as the connecting link between the sympathetic and enteric divisions.4,5

Understanding the Vagus

The vagus system is constantly sending updated sensory information about the state of the body's organs "upstream" to the brain via its afferent nerves. In fact, 80-90 percent of the nerve fibers in the vagus neural network are dedicated to communicating the state of the viscera up to the brain.4

This suggests that only 10-20 percent of these nerves send out motor directives that coordinate the heart/lung complex, digestive functions, and the early stages of elimination through the colon. This is the reason that Dr. Upledger emphasized the importance of enhancing parasympathetic outflow as the basis for activating the body's inherent self-corrective capacities.5

The primary parasympathetic outflow from the brain passes through each of the jugular foramen via the vagal nerves. This is why I conceive of these two apertures as the cradle of autonomic stability. I encourage you to include this as a centerpiece of your therapeutic strategy toward assisting clients to re-gain systemic homeostasis.

Reducing Compression

Let's now explore what we might do to reduce compression within the jugular foramen. The intention here is to identify the primary structures that therapeutic attention has consistently shown to be effective in promoting parasympathetic outflow from the brain. This list is by no means complete so other structures and relationships may also need to be therapeutically addressed.

Reduce tension between the occiput and the atlas by creating a sense of space between them. This is always an excellent first step. I typically accomplish this by stretching the esophagus.

Mobilize the atlas-axis and C2-3 segmental relationships. A reduction in the tone of the upper cervical muscles is a reflection that this has occurred.

Palpate and reduce the tension of the SCM muscles. Dr. Richard MacDonald referred to these as the "guard dog protectors of the cranium."7 And, as they actually attach to the mastoid processes, it is easy to conceive of how their reflexive tension close packs the circumference of the jugular foramen.

Decompress the Lambdoid suture. Simply spreading away from the center of the suture is sometimes enough. By whatever means, easing the tension along this suture enhances blood flow and neural conductivity of the vessels and nerves cradled by the jugular foramen. Gentle bilateral medial compression of the parietal bones also functions to ease the tension of the lambdoid suture from above downward.

Decompress the TMJ. Stretching of the sphenomandibular ligament is an efficient way of doing this. Many other techniques are also possible.

Ease the tension of the stylohyoideus and diagastricus muscles. Their posterior to anterior spanning to the hyoid can also be a contributor to compression of these openings.

The objective here is to highlight that reducing the tensions associated with the jugular foramen is crucially important, especially when dealing with chronic difficulties. Take the time to study the anatomy of this region. Employ techniques that make sense to you to ease the tension of this cradle. Your clients will thank you by referring friends and loved ones.

References

  1. Wikipedia. "Foramen." Wikipedia.com, 2017.
  2. Neuroangio. "Ascending Pharyngeal Artery." Neuroangio.org, 2017.
  3. Radiopaedia. "Juglar Foramen." Radiopaedia.org, 2017.
  4. Alexander DG. "A Look At Compression, Congestion, & Dis-coordination." Massage Today, August 2014;14(8).
  5. Dr. Mark Sircus. "Function of the Vagus Nerve." DrSircus.com, 2014.
  6. John E. Upledger DO. CranioSacral courses (class notes). The Upledger Institute, 1986-93.
  7. Richard MacDonald, DO. Functional Anatomy courses (class notes). The Upledger Institute, 1988-1989.