Functional neurological symptoms (FNS) or Functional Neurological Disorder (FND) is an umbrella term for a wide spectrum of sensorimotor symptoms that resemble neurological conditions.
In FND, the nervous system is experiencing dysregulation, which can lead to varied fluctuating symptoms. FND is a biopsychosocial condition, meaning it involves the body, mind, and emotions working together — and sometimes struggling — as part of the nervous system’s response.
Individuals experiencing functional seizures are often semi-conscious and clients have described that they can hear what is being said, but that they cannot speak, feel foggy, out-of-their-body, numb, or overtaken by a strong energy. Anxiety, depression, symptoms of PTSD, and difficulty concentrating often accompany FND.
The diagnostic process relies on finding clear positive physical signs of the condition, which makes FND not a diagnosis of exclusion. Due to similarities, FND can be misdiagnosed as a neurological disorder, and it can take years for the patient to find out that he, she, or they does not actually have a neurological disorder. FND has been diagnosed in children, teenagers, and adults.
As part of Dr. Moenter’s somatic-based approach to working with functional neurological symptoms, she divides symptoms into two categories, those of a nervous system in sympathetic activation (such as non-epileptic/functional seizures, twitches, jerks, pain, etc.) and those of a nervous system in dorsal vagal collapse (such as paralysis, drop-attacks, limb weakness, etc.).
Contrary to popular belief, anyone can experience the sudden onset of FND. Age, gender, mental health, level of education, or other demographic factors do not seem to have a direct bearing on the onset of FND.
Possible Contributing Factors:
In a sense, functional neurological symptoms can be seen as a physical manifestation of a dysregulated nervous system.
Some correlation exists between PTSD and FND and also being “highly sensitive” and FND. A highly sensitive person is an individual who has sensory processing difficulties, including hypersensitivity to external stimuli, a greater depth of cognitive processing, and high emotional reactivity.
FND includes functional movement disorders and tremors, idiopathic non-epileptic seizures, drop-attacks, visual symptoms such as blindness, photophobia and double vision, speech impairment and stutter, touch sensitivity, chronic pain, gate and balance problems, as well as paralysis and weakness.
Cognitive and emotional challenges, memory loss, brain fog, fatigue, anxiety, or avoidance often accompany FND. In addition, symptoms of altered awareness, including dissociative symptoms, derealization, and depersonalization, are very common.
Current research on dissociation builds on a tradition dating back to Janet’s (1887) distinction between psychological phenomena, or psychoform dissociative symptoms, and bodily phenomena, or somatoform dissociative symptoms. FND is typically understood to primarily involve the latter (Nijenhuis et al., 1996; Pick et al., 2017; Vuilleumier & Cojan, 2011).
Explanations for why individuals with FND are experientially disconnected from their bodies are manifold: dissociation as a survival response to trauma; cultural, familial, or religious reasons; alexithymia (difficulty identifying feelings and distinguishing between feelings and the bodily sensations of emotional arousal); or impaired interoception (the ability to sense the internal states of the body). The most widely accepted contributing etiologic factor, however, is prior exposure to chronic stress and trauma.
Dr. Moenter talks about dissociation happening on a continuum from “spacing out” to out-of-body experiences and full dissociative states such as non-epileptic seizures. The healing process involves learning how to self-regulate dissociative states early so as to not fully disconnect from the present moment experience. The ability to stay present allows for a greater capacity to be mindful of changes in nervous system activation (FND symptoms).
A typical feature of functional seizures is involuntary movement that resembles epileptic seizures. Those movements can be micro-movements (twitches, spasms, subtle shaking etc.) or macro-movements (visible large movements of the limps, head, upper or lower body) often with loss of consciousness. Some individuals have described still having self-awareness but not being able to react to the environment (responding to people asking questions, or protecting oneself from physical harm) while also not being able to self-regulate their nervous system enough to stop the seizure activity.
For some individuals with FND, symptoms are more pronounced in the realm of a hypo-activated nervous system (not enough activation). When the nervous system is in a state of parasympathetic-dominant hypo-activation (or dorsal vagal collapse), the body shuts down. This shut-down can be experienced as partial or full paralysis or weakness.
Other symptoms that can accompany the dorsal vagal collapse can be the inability to think, slurred speech, drop attacks and blackouts, spaciness and extreme fatigue, loss of bladder/bowel function, collapse, numbness, depersonalization, or derealization
Many individuals with FND experience sensory sensitivities or sensory symptoms. Sensory sensitivities can impact all senses (touch, smell, sound, taste, vision, and interoception). Lights can feel too bright, touch uncomfortable or even painful, sounds intrusive, smells overpowering, taste intolerable and the ability to sense inner body sensations (interoception) is often lacking.
The central nervous system is designed to filter out redundant and unnecessary stimuli and organize sensorimotor information into an integrated experience. This process is called the “gating mechanism,” and it may be dysregulated in many clients with FND who describe a variety of sensory challenges that manifest as over-sensitivity or under-sensitivity.
Over-sensitivity, or “sensory overload,” implies a heightened sensitivity to touch, sounds, sights, textures, smells, and other sensory stimuli. Under-sensitivity can manifest as a lack of responsiveness to factors such as temperature, touch, or noise. It is possible that these symptoms are caused by sensorimotor gating impairments that prevent individuals from integrating information from internal and external sources as normal.
Dr. Moenter explains how sensory processing works and how you can regulate and increase your ability to be with sensory stimuli. Learning about the gating mechanism of the brain, your boundary style, and concrete boundary tools might increase your ability to process sensory stimuli and feel less negatively impacted by sensory stimuli.
Trauma is the result of experiencing inescapably stressful events that overwhelm an individual’s existing coping mechanisms while obstructing information-processing abilities. It affects memory in two ways, modifying both sensorimotor and affective levels of memory formation and recall and often producing the symptoms of somatoform and psychoform as seen in FND.
Some individuals with FND have experienced chronic stress or trauma prior to the onset of FND. The exposure to life-altering adverse events can contribute to the dysregulation of the autonomic nervous system. Since FNDcourage is based on the idea that FND is an expression of a dysregulated nervous system (too much or too little activation), part of the healing process is undoubtedly the work with and resolution of any adverse nervous system changes resulting from chronic stress and/or trauma.
Although a direct causal connection between trauma and the onset of FND has not yet been identified, trauma is widely believed to be a contributing factor, alongside adverse childhood experiences (ACE). For instance, several studies have concluded that individuals with FND exhibit elevated rates of post-traumatic stress disorder (PTSD), and those with FND display disproportionately high incidence of involuntary dissociative states.
You will learn about resilience and how to increase your on resilience in the face of stressful external and internal experiences. Resilience is your ability to quickly and fully recover from challenging, stressful, and traumatic events.
Being resilient means you have the capacity to face stressors, to lean into discomfort, instead of avoiding challenges. Part of the model of how Dr. MOenter works is to NOT use the word “triggers.” Many professionals talk about “triggers” in the context of FND. What Dr. Moenter has seen in her work with FND is that people naturally orient away from “triggers” creating a pattern of avoidance. Such avoidance, over time, leads to a very limited lifestyle and a lack of trust and strength necessary to lean into the discomfort of FND, which eventually will help reduce symptoms.
Dr. Moenter introduces the concept of “precursors” feelings, thoughts, and physical sensations that can be an indicator that your nervous system is at the beginning stages of dysregulation.
“True freedom means living our lives fully, not avoiding, not “coping,” but truly developing the capacity to be with all that life offers us.” Afra Moenter, Ph.D.
Functional Movement Disorders can be divided into tremors, twitches and jerks, gait problems (difficulty walking), functional weakness. These functional symptoms are not caused by damage or disease of the nervous system.
Dr. Moenter talks about involuntary and voluntary movements, and how to relate to and potentially ease involuntary symptoms in your body.
Dr. Moenter explores emotional imbalances as part of FND. Research shows that individuals with FND have
Common emotions that individuals with FND feel are shame, anxiety, despair, hopelessness, helplessness, and fear. Dr. Moenter’s explains how emotions can be an expression of a regulated (sadness, curiosity, anger, fear etc.) or a dysregulated (terror, rage, shame, obsession etc.) nervous system. As part of the FNDcourage course you will learn how to identify your emotions as they relate to your nervous system activation and learn how to self-regulate your emotional state. Such emotional self-regulation can positively impact your functional neurological symptoms.
Dr. Moenter also explores how emotions contribute to your body posture, how you hold yourself in your body, and how in turn that experience might make you more susceptible to certain FND symptoms. By learning about and changing your Emotional Anatomy (Stanley Keleman) you will increase your interoception (body awareness) and increase your ability to regulate your nervous system.
Many individuals with FND describe functional cognitive symptoms. Symptoms vary, but can often include:
If you experience any of these symptoms as part your FND, your challenges might not be due to you loosing your intellectual capacity or curiosity. Dr. Moenter views cognitive symptoms as an often temporary limitation; potentially caused by severe dissociative states and/or a result of the chronic stress of FND (or other life-altering events). The exposure to chronic stress and trauma can impair the functionality of the pre-frontal cortex (responsible for executive function, decision making, etc.) and therefore can leave you with a limited capacity to think clearly or make sound decisions for yourself.
Words matter, especially when you’re navigating something as complex as Functional Neurological Disorder.
This glossary is here to gently translate medical language into clear, approachable definitions you can trust. When you understand the words being used, it becomes easier to feel seen, ask thoughtful questions, and move forward with greater clarity and confidence.
You deserve information that supports you, not overwhelms you.
A
Acceptance and Commitment Therapy (ACT) — A therapy that helps you notice difficult thoughts and feelings without getting stuck in them, then choose actions that align with your values.
Accessibility — Designing resources so everyone, regardless of symptoms or abilities, can easily understand and use them.
Autonomic Nervous System (ANS) — The part of your nervous system that automatically controls things like heart rate and breathing, and plays a big role in stress and calm states.
B
Body‑Based Approach — Any technique that works through movement, breath, or touch to calm the nervous system (e.g., gentle physiotherapy, yoga, tai chi).
Bodily Distress Disorder (BDD) — An ICD‑11 diagnosis where ongoing body symptoms cause distress and daily disruption, even after major disease is ruled out.
Boom-Bust Cycle — The pattern of pushing hard on good days (“boom”) and then needing long recovery time (“bust”).
C
Care Team — The group of professionals and support partners who work together on your wellness plan.
Cognitive Behavioral Therapy (CBT) — A structured talk therapy that teaches practical ways to change unhelpful thoughts and behaviors.
Complex Regional Pain Syndrome (CRPS) — A chronic pain condition that sometimes occurs alongside FND.
Conversion Disorder — An outdated medical term once used for FND. We use “Functional Neurological Disorder” instead.
D
Daily Living Strategy — A Fit + Function resource that offers real‑world tips for managing everyday activities with FND.
Dissociative Seizure — Another name for Psychogenic Non‑Epileptic Seizure (see PNES).
E
EEG (Electroencephalogram) — A test that records brain-wave patterns; in FND, results look normal even during a functional seizure.
Eight Dimensions of Wellness — A whole‑person framework we use to organize content: Physical, Emotional, Social, Intellectual, Occupational, Financial, Environmental, and Spiritual wellness.
Emotional Wellness — Understanding, accepting, and managing your feelings.
Environmental Wellness — Creating safe, calming spaces that support your health.
Evidence‑Based — Backed by high‑quality research rather than anecdote or opinion.
Expert Interview — A Fit + Function content type featuring insights from clinicians and researchers.
F
Financial Wellness — Managing money matters in a way that reduces stress and supports health goals.
Flare — A short spell when your usual FND symptoms suddenly get worse.
Functional Movement Disorder (FMD) — A movement‑focused form of FND that may cause tremors, jerks, or gait changes.
Functional Neurological Disorder (FND) — A brain‑body communication problem that leads to real symptoms—such as seizures, weakness, or movement changes—despite normal scans.
Functional Overlay — When FND symptoms sit on top of another neurological condition (e.g., epilepsy), making the picture more complex.
Functional Seizure — Seizure‑like episodes in FND. They look like epilepsy on the outside, but brain‑wave tests are different. Also called PNES or dissociative seizures.
Functional Somatic Syndromes (FSS) — A family of conditions—like fibromyalgia and irritable‑bowel syndrome—where body symptoms happen without clear tissue damage.
Functional Weakness — Real muscle weakness that changes from moment to moment because of mis‑signals between brain and body, not because the muscle is damaged.
G
Graded Exposure / Graded Activity — A step-by-step plan to rebuild confidence and ability by gently increasing a challenging activity.
Graded Exercise Therapy (GET) — A structured program that slowly increases physical activity; once common, now used cautiously because results are mixed.
Grounding — Simple techniques (like feeling your feet on the floor) that bring attention to the present moment and calm the nervous system.
H
Healthcare Provider — Any licensed professional involved in diagnosis, treatment, or support (e.g., neurologist, physiotherapist, psychologist).
I
Interoception — Your brain’s ability to sense internal body signals like heartbeat or hunger; often targeted in FND therapies.
Intellectual Wellness — Engaging in mentally stimulating activities that expand knowledge and skills.
J
K
L
Lived Experience Story — A Fit + Function article where someone shares their personal journey with FND to offer hope and practical tips.
M
Mindfulness — Paying attention, on purpose and without judgment, to the present moment.
MRI (Magnetic Resonance Imaging) — A scan that shows the brain’s structure; in FND, it usually looks normal because the problem is in function, not damage.
Multidisciplinary Care — Treatment that brings together experts from different fields to address FND from many angles.
Multidisciplinary Team (MDT) — A group of specialists—like neurologists, psychologists, and physiotherapists—who work together on complex cases.
N
Neurologist — A doctor who specializes in the brain and nervous system and often leads FND diagnosis.
Neurobehavioral Therapy (NBT) — A rehabilitation program that retrains movement and thinking patterns to reduce FND symptoms.
Neuroplasticity — The brain’s ability to change and create new connections—a hopeful engine for recovery.
Neuroplastic Exercise — A practice (movement, breath, or mind-body task) designed to help the brain build healthier pathways.
Non-Epileptic Attack Disorder (NEAD) — Another name for Functional Seizure (also called PNES). It describes real seizure-like episodes that look like epilepsy on the outside, but brain-wave tests are different. See Functional Seizure / PNES for details.
O
Occupational Wellness — Finding purpose and balance in work, volunteering, or daily roles.
P
Pacing — Balancing activity and rest to avoid the “boom-bust” cycle of overdoing it one day and crashing the next.
Physical Wellness — Caring for your body through movement, sleep, and nutrition.
Polyvagal Theory — A science model explaining how the vagus nerve influences feelings of safety or threat in the body.
Psychogenic Disorder — A broad historical label that implies symptoms come only from the mind. Considered stigmatising and imprecise.
Psychogenic Non‑Epileptic Seizure (PNES) — FND seizures that look like epilepsy but have different brain signal patterns.
Q
Quality of Life (QoL) — A broad measure of how satisfied you feel with your daily functioning and wellbeing.
R
Recovery & Management — A Fit + Function content category focusing on strategies to reduce symptoms and boost everyday functioning.
Research Translation — A plain‑language Fit + Function summary that turns new scientific findings into practical guidance.
Resource Summary — A concise overview of books, podcasts, or videos with takeaways for living well with FND.
S
Safe and Sound Protocol (SSP) — A listening therapy using filtered music to help the nervous system feel safer and more regulated.
Self‑Regulation — Skills that help you notice and shift your physical or emotional state toward calm.
Sensorimotor Retraining — Therapy that retrains how the brain plans and senses movement to reduce FND symptoms.
Sensory Grounding — Using senses—like noticing three things you see or hear—to bring attention back to the present moment.
Social Wellness — Building healthy, supportive relationships.
Somatic Exercise — Movement or posture practice that focuses on sensing and releasing body tension.
Somatic Symptom Disorder (SSD) — A condition where ongoing body symptoms cause a lot of worry and life disruption, even after doctors rule out major disease.
Somatic Tracking — Paying gentle, curious attention to a symptom in the body to help the brain “recalibrate” its alarm signals.
Support Partner — A friend, family member, or caregiver who actively helps someone living with FND.
Symptom Diary — A daily log of symptoms, triggers, and improvements that guides personalized care.
T
Trauma‑Informed Care — An approach that assumes past trauma may influence current health and prioritizes safety, choice, and empowerment.
Trigger — Anything—like stress, noise, or lack of sleep—that can set off or worsen FND symptoms.
U
V
Vagus Nerve — The longest cranial nerve, central to Polyvagal Theory, that influences calm, digestion, and heart rate.
W
Whole‑Person Approach — Looking at physical, emotional, and social factors together, rather than treating symptoms in isolation.
Window of Tolerance — The nervous-system zone where you feel calm enough to think clearly and move well; outside it, symptoms often flare.
X
Y
Z
You don’t have to navigate FND alone.
Across the FND community, there are other nonprofits, advocacy organizations, specialty clinics, and educational resources designed to help. Yet, many individuals and families find them or know they exist. Whether you’re newly diagnosed or looking for the next step in your care, these resources are here to help you feel informed, supported, and less alone as you move forward.
These organizations provide support, education, and advocacy for people living with FND:
Expand your understanding of FND with these available resources:
Rewire OT – A central location for Functional Neurological Disorder resources and highlighting the role Occupational Therapy plays in patient care.
Support for clinicians and researchers dedicated to advancing the diagnosis, treatment, and understanding of Functional Neurological Disorder:
Explore FNDcourage videos and workshop recordings designed to educate, encourage, and support you. From expert-led discussions to practical nervous system tools, these replays allow you to learn at your own pace and revisit the insights that matter most on your journey.
