Some bodies stay stuck in fight-or-flight because the brain never gets a clear all-clear signal. The upper neck is one of the body's main position sensors, and an old injury there can feed the brainstem distorted information. The brain reads that mismatch as danger and keeps the sympathetic nervous system switched on — heart racing, muscles tight, sleep broken.
Why does your neck decide whether you feel safe?
The upper neck is one of the richest sources of position information in your whole body. The deep suboccipital and upper cervical muscles carry an unusually high density of proprioceptive receptors, which is why they play a central role in telling your brain where your head is in space (Armstrong et al., 2008). That signal travels into the brainstem, right beside the centers that govern your autonomic nervous system — the fight-or-flight and rest-and-digest balance.
So your neck isn't just holding your head up. It is constantly reporting to your brainstem whether the world is steady and whether you are safe. When that report is clean, the brain can relax. When it isn't, the whole system stays on guard.
What happens when an upper-neck injury damages that signal?
Picture an injury to the upper neck — a whiplash, a fall, a concussion. The joints and muscles stop reporting cleanly and send a distorted, mismatched signal. Your brain compares the input from your neck, your inner ear, and your eyes, and they no longer agree with each other. This kind of sensory conflict is a well-documented driver of cervicogenic dizziness and disorientation (Devaraja, 2018).
A brain receiving conflicting information about something as basic as which way is up does not relax. This same disruption shows up after head and neck trauma: concussion has been repeatedly linked to measurable autonomic nervous system anomalies (Pertab et al., 2018). The threat isn't out in the world — it's a faulty signal coming from the top of the spine, and the body responds as if a real threat were present.
Why does the brain keep the sympathetic system switched on?
Your sympathetic nervous system is the "fight-or-flight" branch: it raises heart rate and blood pressure, tightens muscles, and suppresses digestion to prepare you for a threat (Waxenbaum et al., 2025). Its counterpart, the parasympathetic "rest-and-digest" branch, is supposed to bring you back down once the danger passes.
When your brainstem keeps reading a mismatched neck signal as danger, it never issues that stand-down order. The sympathetic branch stays dominant for months or years — which is why so many people feel wired and exhausted at the same time, with anxiety they can't name, a gut in knots, and a resting heart rate that sits too high. That persistent activation is the "lock," and it often gets mislabeled as pure anxiety, dizziness, or dysautonomia rather than a mechanical problem in the neck.
Can correcting the upper neck actually calm fight-or-flight?
For some people, yes. I have felt it in my own body. The night before a big presentation, I lay in bed with my heart pounding and my whole body braced, even though nothing in the room was a threat. My nervous system simply could not find the off switch.
When I finally had my upper neck adjusted — a precise correction to that junction — my body dropped out of fight-or-flight within about two minutes. My heart rate came down, my breathing opened up, my head cleared. Nothing about the presentation had changed. What changed was the signal my brainstem was receiving from my neck. When the input corrected, the alarm stood down. You can read more about the mechanics of this in what's actually happening in the nervous system during dysautonomia.
Why won't I talk around what this really means?
This matters more than feeling tense. When you are stuck in fight-or-flight for months or years, it changes what it feels like to be alive. I know that ground personally. Years ago, while I was overseas, I went through a stretch of depression I would not wish on anyone, and I have lost two friends to suicide.
Here is what I have come to believe. People in that place don't hate their life — they hate life feeling like this. They hate the version of being alive that a hijacked nervous system hands them: the dread, the exhaustion, the flat certainty that nothing will ever feel okay again. That feeling is real, but it is a state, not a verdict. And when part of what drives that state is a physical signal from an injured neck, that is something we can actually address.
I am not telling you a neck adjustment cures depression, and I won't pretend it does. I am telling you that for some people, a piece of the puzzle no one has ever checked is sitting at the very top of their spine, jamming the alarm system in the "on" position. Finding that piece can give a person room to breathe — and sometimes that room is enough to make the rest of the work of healing possible.
What should you do if you've been stuck on high alert?
If your body has been running hot — anxiety, broken sleep, a racing heart, a gut that won't settle — and no one has examined your upper neck, that may be the piece that has been missing. This is a mechanical problem with a mechanical answer, and it is worth checking before you accept that this is simply how you have to live. If your history includes a head or neck injury, the connection is worth taking seriously; you can also compare how much force injures your neck versus your brain. Checking whether an old neck injury is keeping your alarm system switched on is the work we do at Cerebral in St. Petersburg.
References
- Armstrong B, McNair P, Taylor D. Head and Neck Position Sense. *Sports Medicine*. 2008. https://link.springer.com/article/10.2165/00007256-200838020-00002
- Devaraja K. Approach to cervicogenic dizziness: a comprehensive review of its aetiopathology and management. *European Archives of Oto-Rhino-Laryngology*. 2018. https://link.springer.com/article/10.1007/s00405-018-5088-z
- Pertab JL, et al. Concussion and the autonomic nervous system: An introduction to the field and the results of a systematic review. *NeuroRehabilitation*. 2018. https://pubmed.ncbi.nlm.nih.gov/29660949/
- Waxenbaum JA, et al. Anatomy, Autonomic Nervous System. *StatPearls*. 2025. https://www.ncbi.nlm.nih.gov/books/NBK539845/