The Vagus Nerve and the Neurogenic Tremor: The Science Behind TRE®

Every mammal has an inborn mechanism for discharging stress from the body. Watch a wild animal after a threat has passed — a deer, a rabbit — and it will often tremble or shake before returning to grazing, as though nothing happened. Humans have the same reflex. Most of us have simply lost easy access to it.

What is the vagus nerve?

The vagus nerve, also known as the vagal nerves, carry signals between your brain, heart and digestive system. They’re a key part of your parasympathetic nervous system. Vagus nerve damage can lead to gastroparesis, food not moving into your intestines. Some people with vasovagal syncope faint from low blood pressure. Vagus nerve stimulation (VNS) can treat epilepsy and depression.

Where TRE® Comes From

Tension and Trauma Releasing Exercises were developed by Dr David Berceli, a trauma intervention educator with a background in both social work and therapeutic bodywork. Working with populations exposed to chronic and acute stress — including communities in active conflict zones — Berceli observed the same phenomenon: bodies under sustained threat wanted to tremor, and when allowed to do so safely, that tremoring appeared to support genuine physiological recovery.

From this, he developed a sequence of seven exercises designed to gently fatigue and stretch specific muscle groups, particularly through the hips and legs, in order to invite the body's natural tremor mechanism back online.

Polyvagal Theory and the Nervous System

Stephen Porges' polyvagal theory offers a useful map for understanding what TRE® works with. The nervous system moves between three broad states: ventral vagal (safety and connection), sympathetic (mobilised fight-or-flight), and dorsal vagal (shutdown or freeze). Chronic stress tends to leave people oscillating between sympathetic activation and dorsal collapse, with the ventral vagal state — where genuine rest and connection become possible — increasingly hard to access.

The neurogenic tremor appears to support a return toward ventral vagal functioning. It is not a technique performed on the nervous system from the outside; it is the nervous system's own regulatory mechanism, simply given the conditions to complete itself.

What Is Actually Happening in the Tremor

The tremors activated in a TRE® session are involuntary and self-limiting. They typically begin in the legs, where the exercises create the initial fatigue, and can move through the pelvis, spine, and upper body as a session progresses. This is not muscular exhaustion. It is closer to what happens when a wound-up spring is finally allowed to unwind — a discharge of held activation that the body has often been carrying, in some cases, for years.

Why Movement Reaches What Talking Sometimes Can't

Talk-based approaches work primarily through the cortex — the thinking, narrating part of the brain. Chronic stress and trauma, however, are held largely in older, subcortical structures that do not require language to process or release. This is part of why insight into a problem — fully understanding why you feel a certain way — does not always translate into the body actually letting go of it. TRE® bypasses the need for narrative altogether, working directly with the physiology.

A Complement, Not a Replacement

None of this positions TRE® as a substitute for talk therapy or medical care where those are needed. The research base for TRE®, while growing, is still relatively young compared to more established modalities, and it is generally best understood as a complementary practice — one that works alongside other forms of support rather than instead of them.

What it offers is access to a layer of the nervous system that language-based approaches were never designed to reach directly. For many people, that combination — the cognitive processing offered by talk therapy, paired with the physiological discharge offered by TRE® — proves more complete than either approach on its own.

I integrate TRE® into my one-to-one sessions, workshops, and retreats. Find out more at whoislikemike.com.