Five Things to Know about Functional Neurological Disorder

Shortly after the beginning of the COVID crisis, I met my first client with functional neurological disorder (FND). I've practiced in the mental health field for more than a decade. Yet, I'd never heard of this significant diagnosis. As I set out to educate myself, I realized that my lack of awareness is not uncommon.

While the diagnosis of functional neurological disorder has increased exponentially, and psychotherapy is a commonly recommended treatment (Aybek and Perez, 2022), many, including therapists, remain unfamiliar with the condition.

FND is a subtype of conversion disorder included in The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). It can present with an array of neurological symptoms ranging from tics to non-epileptic seizures to periods of paralysis and hallucinations (Espay et al., 2018). While these symptoms may appear similar to what would be triggered by known neurological causes, with FND, no clear physical etiology has been identified. Rather, it is hypothesized that FND may be the result of an extreme reaction to the stress hormone cortisol (Weber et al., 2024), causing it to land square on the border between psychiatry and neurology. With many exposed to unprecedented levels of stress during the COVID crisis, it makes sense that the prevalence of the condition would rise as well.

Here are five things to know about FND:

1. Functional Neurological Disorder Is Not Faked.

While symptoms of FND do not fall within the ranges of other neurological conditions that usually cause those symptoms—for example, with non-epileptic seizures, a person may show all signs of a seizure without any unusual brain activity to be picked up on an EEG—these symptoms are not fake. The symptoms of FND are very real and not an attempt at malingering. Telling someone with FND to just "stop" or treating it as a feign for attention will not help.

2. Functional Neurological Disorder Is Treatable.

Although best practices for FND are still being explored, treatment protocol typically involves a combination of psychotherapy, physical therapy, and occupational therapy under the supervision of a neurologist or psychiatrist.

3. Functional Neurological Disorder Can Be Thought of Almost as an Allergy to Stress.

When symptoms are described as stress-induced, they may seem downplayed, yet in FND, the reaction is thought to be due to an interaction with the stress hormone cortisol. Rather than thinking of FND as a stress-induced disorder, thinking of it as an allergy to stress may be more productive. Treatment can improve one's ability to tolerate stress.

4. Most People With Functional Neurological Disorder Have Other Conditions as Well.

Other psychiatric comorbidities may be present in 40 to 100 percent of individuals with FND, according to one study, with anxiety, mood disorders, and childhood trauma being the most common (Carle-Toulemonde et al., 2023).

5. Misunderstanding Hurts

Many individuals with lived experience of FND have had negative interactions with the medical community. From accusations of "faking" to dismissal, these reactions and misdiagnoses can be extremely harmful and delay a person from receiving effective care. We should all educate ourselves about FND.