Understanding Functional Neurological Disorder (FND): A Nervous System and Trauma-Informed Perspective

Functional Neurological Disorder (FND) can feel confusing and destabilizing — especially when symptoms are real but medical tests appear normal.

People experience real symptoms — weakness, tremor, gait changes, non-epileptic seizures, speech or sensory disruption — and are told their MRI is normal.

For many, the most destabilizing part is not just the symptom. It is the doubt that follows.

Modern neurology no longer views FND as imagined or voluntary. It is increasingly understood as a disorder of brain network functioning, not structural damage (Perez et al., 2021).

The circuits are present. The coordination between them is altered.

This article offers one perspective — through a nervous system and trauma-informed lens — not as a single cause, but as a way to understand how regulation, threat processing, and movement intersect.

Functional Neurological Disorder as a Brain Network Condition

In FND, the problem is not tissue damage. It is network communication.

Research over the past decade suggests altered connectivity between:

• Motor networks

• Attention and salience networks

• Emotional/threat processing systems

  
  

Movement is not simply a command sent from the brain to the body. It is generated through predictive processing.

When you move your arm, your brain:

• Forms a motor plan

• Predicts what the movement will feel like

• Compares prediction with incoming feedback

  
  

This predictive model is well supported in neuroscience (Edwards et al., 2012).

Healthy movement requires both activation and inhibition. The brain constantly applies “brakes” to ensure movement is appropriate and safe.

In FND, one way to understand symptoms is that inhibitory networks override or distort motor output.

The person intends to move. The command is generated. But execution is disrupted.

This helps explain why symptoms feel involuntary.

The Nervous System in Functional Neurological Disorder

The nervous system is built for protection.

Under acute threat, movement may freeze. Under chronic stress, regulation can become unstable.

Over time, prolonged stress exposure may lead to:

• Heightened threat sensitivity

• Autonomic imbalance (fight/flight or shutdown)

• Dissociation during overload

• Increased vigilance toward bodily sensations

When protective systems remain amplified, they can influence motor networks.

This does not mean trauma causes FND.

It means that nervous system dysregulation may increase vulnerability to functional symptoms in some individuals.

From this lens, symptoms can be understood not as failure — but as miscalibrated protection.

Trauma-Informed Care in Functional Neurological Disorder

A trauma-informed perspective does not assume that all FND is trauma-driven.

It does not assume psychological weakness. It does not reduce symptoms to emotion.

Instead, it recognizes that:

• Adversity and chronic stress are more common in FND populations than in controls.

• Trauma can shape autonomic regulation and threat detection over time.

• Dissociation and altered body awareness may complicate symptom patterns.

A trauma-informed stance asks: What has this nervous system adapted to?Rather than: What is wrong with this person?That shift reduces shame and guides safer care.

I’ve written more extensively about how chronic stress reshapes nervous system regulation in this piece.

Somatic Work and Regulation in FND

Somatic approaches focus on nervous system regulation and embodied awareness. They are not about uncovering hidden memories or forcing emotional processing. When integrated responsibly into FND care, they aim to stabilize the regulatory systems that influence movement.

In some individuals — particularly those with histories of chronic stress or trauma — dissociation can complicate how symptoms present.

Dissociation is not dramatic. It is often subtle.

It may look like:

• Feeling disconnected from a limb

• A sense that movement does not feel fully “owned”

• Emotional numbness during stress

• Sudden shifts into shutdown or collapse

Research suggests that in at least some people with FND, there can be alterations in how the brain integrates body awareness, agency, and motor output. When body awareness is either amplified (hypervigilance) or blunted (dissociation), motor control can become less stable.

This does not mean symptoms are psychological. It means that the systems that integrate sensation, attention, and movement are sensitive to stress.

From a somatic perspective, the goal is not to analyze symptoms. It is to improve regulation and integration. Somatic work may support:

Autonomic Stability

Building tolerance for activation without tipping into panic, freeze, or collapse.

Integration of Body Awareness

Strengthening accurate, tolerable interoception — not symptom scanning, but grounded sensing.

Restoration of Agency

Creating repeated experiences of safe, successful movement so the brain updates its prediction of threat.

In predictive processing terms, if the brain expects movement to be unsafe, inhibition may increase (Edwards et al., 2012). When movement becomes associated with safety and stability, prediction can gradually shift.

For individuals with dissociation, this work must be slow and titrated. Increasing body awareness too quickly can intensify symptoms. Capacity building comes first.

Somatic work does not replace rehabilitation. It can provide the regulatory foundation that allows physical retraining to take hold.

Interdisciplinary Treatment for Functional Neurological Disorder

FND does not sit neatly in one discipline.

Best-practice recommendations emphasize coordinated care that may include:

• Neurology (clear diagnosis and explanation)

• Physiotherapy or occupational therapy (goal-directed movement retraining)

• Psychological support when appropriate

• Somatic-informed regulation work

Consensus guidelines for functional motor disorders highlight education, attention redirection, and graded movement retraining as core elements of recovery (Nielsen et al., 2015).

No single modality is sufficient for everyone.

FND lives at the intersection of neurology, rehabilitation, and mental health. Treatment is most effective when it reflects that complexity.

If You Are Reading This While Symptomatic

If you are currently experiencing symptoms, it can feel frightening and destabilizing.

Symptoms may fluctuate. They may worsen under stress. They may improve and return. That variability does not mean you are imagining them. It reflects the functional nature of the condition.

From a nervous system perspective, your body may be applying too much protection.

Protection is not failure. It is an overactive system trying to keep you safe.This is not something you fix through force or willpower. Pushing often increases inhibition. Fighting symptoms often amplifies them.

Instead, recovery tends to involve:

• Clear explanation and validation

• Gradual, goal-directed retraining

• Attention shifted outward rather than inward

• Regulation work that builds capacity slowly

• Coordinated care with professionals who understand FND

Improvement is often incremental. There may be setbacks. That does not mean you are broken.

Because FND reflects altered function rather than structural loss, change is possible (Perez et al., 2021). The brain remains capable of relearning. Recalibration is not dramatic. It is steady. And it is rarely done alone.

Selected References

• Edwards MJ et al. (2012). A Bayesian account of functional motor and sensory symptoms. Brain.

• Perez DL et al. (2021). A decade of progress in motor functional neurological disorder. JNNP.

• Nielsen G et al. (2015). Physiotherapy for functional motor disorders: consensus recommendations. JNNP.