Dysautonomia and the Nervous System, Explained

During dysautonomia, the autonomic nervous system loses its ability to shift smoothly between "fight-or-flight" and "rest-and-digest." Instead of the two branches balancing each other, one gets stuck in overdrive or underdrive. The result is a body that misreads its own internal signals, producing a racing heart, dizziness, stalled digestion, and deep fatigue.

What is the autonomic nervous system, and what does it do?

The autonomic nervous system (ANS) is the part of your nervous system that runs in the background, regulating heart rate, blood pressure, digestion, breathing, and temperature without any conscious effort (LeBouef et al., 2023). That automatic quality is the whole point: it is supposed to keep your body in balance while you go about your day. When it works well, you never notice it. When it falters, you feel it everywhere.

What are the sympathetic and parasympathetic branches?

The ANS has two main branches that pull in opposite directions. The sympathetic branch is your "fight or flight" system: it raises heart rate, dilates pupils, slows digestion, and readies you to respond to stress. The parasympathetic branch is your "rest and digest" mode: it slows the heart, boosts digestion, and promotes healing and relaxation (LeBouef et al., 2023). In a healthy system, these two work like a teeter-totter, one calming as the other rises.

What happens when the balance tips too far in dysautonomia?

In dysautonomia, the teeter-totter gets stuck, and that is when problems arise. If the sympathetic side stays overactive, the body lives in constant overdrive, which can drive rapid heart rate (as in POTS), poor digestion, disrupted sleep, anxiety-like symptoms, and cold hands and feet. If the parasympathetic side becomes dominant in the wrong way, people may experience brain fog and fatigue, low blood pressure, dizziness or fainting, low mood, and sluggish gut motility. It is rarely that one branch is simply "bad." The core issue is dysregulation, the body's inability to shift gears smoothly (Sánchez-Manso et al., 2023).

Why is the brainstem the master regulator?

At the core of this system sits the brainstem, the main hub for autonomic control. Regions within it, including the medulla, receive data about your body's internal state and decide how to respond, raising blood pressure, slowing the heart, stimulating digestion, or releasing stress hormones (Iordanova & Reddivari, 2023). Because so much autonomic traffic converges here, the brainstem's ability to read incoming signals accurately matters enormously to how regulated you feel.

How can the upper neck interfere with autonomic signals?

Here is where anatomy becomes interesting. The craniocervical junction, where your skull meets the top two neck bones, is the anatomical neighborhood that surrounds the brainstem. In our clinical experience, when this area is under strain from trauma, posture, or hypermobility, it may interfere with the signals traveling in and out of the brainstem. This is why we pay close attention to the upper neck and to any coexisting neck pain in people with autonomic symptoms.

What does dysautonomia feel like? A simple analogy

Imagine the brainstem is the thermostat in your home. It constantly monitors the internal temperature, your body's signals, and adjusts accordingly. But if someone drapes a towel over that thermostat, it starts getting faulty readings. The heat might crank on when you are already warm, or the AC might cut out in the middle of summer. That is the idea behind how craniocervical tension may affect autonomic regulation: the control center is intact, but the input and output are distorted.

Where might upper cervical chiropractic help?

At Cerebral, we do not chase symptoms. We focus on clearing interference, especially at the craniocervical junction, so the nervous system can regain its ability to self-regulate. When pressure is relieved at the top of the spine, the brainstem may be better able to return to baseline function. This gentle, upper-cervical approach is central to how we work with people whose bodies feel stuck in overdrive.

References

LeBouef T, Yaker Z, Whited L. Physiology, Autonomic Nervous System. *StatPearls*. 2023. https://www.ncbi.nlm.nih.gov/books/NBK538516/
Iordanova R, Reddivari AKR. Neuroanatomy, Medulla Oblongata. *StatPearls*. 2023. https://www.ncbi.nlm.nih.gov/books/NBK551589/
Sánchez-Manso JC, Gujarathi R, Varacallo MA. Autonomic Dysfunction. *StatPearls*. 2023. https://www.ncbi.nlm.nih.gov/books/NBK430888/
Vernino S, et al. Postural orthostatic tachycardia syndrome (POTS): State of the science and clinical care from a 2019 National Institutes of Health Expert Consensus Meeting - Part 1. *Autonomic Neuroscience*. 2021. https://pubmed.ncbi.nlm.nih.gov/34144933/

Frequently asked questions

Is dysautonomia caused by one branch being broken?

Usually not. The problem is dysregulation, the inability to shift smoothly between the sympathetic and parasympathetic branches, rather than a single branch failing. One side may dominate at the wrong time, which is why symptoms can swing between overdrive, like a racing heart, and underdrive, like fatigue and dizziness (Sánchez-Manso et al., 2023).

What role does the brainstem play in dysautonomia?

The brainstem is the central hub for autonomic control. Areas within it, including the medulla, help regulate heart rate, blood pressure, and digestion by reading signals from the body and responding (Iordanova & Reddivari, 2023). If the information reaching or leaving the brainstem is distorted, autonomic responses can become poorly timed and inconsistent.

Can upper cervical chiropractic cure dysautonomia?

Upper cervical care is not a cure, and we avoid overpromising. Our goal is to reduce interference at the craniocervical junction so the nervous system has a better chance to self-regulate. Whether the upper neck is contributing to your symptoms is something a proper evaluation and imaging help determine.

Why does POTS involve such a fast heart rate?

POTS, or postural orthostatic tachycardia syndrome, involves an excessive rise in heart rate on standing and is associated with autonomic dysfunction (Vernino et al., 2021). It reflects the sympathetic-dominant end of dysregulation, where the body reacts to standing as if it were a threat rather than a routine change in posture.