FND: A Diagnosis That Shuts Doors?
FND Nope
Moderator
Functional neurological disorder (FND) has a colourful and deeply troubling history. Originally referred to as hysteria, early physicians were convinced that it arose from women's lack of sexual satisfaction or "frustration" and often used sexual stimuli such as pelvic massage as a so-called treatment—effectively sexual abuse.
By the late 19th century, Sigmund Freud reconceptualised the term with
conversion disorder, proposing that psychological conflicts were converted into physical symptoms, a view still influential in psychiatry and psychology today.
Under Conversion Disorder criteria, it functioned largely as a diagnosis of exclusion, even though the formal criteria also included psychological association rather than being purely rule-out.
Today, FND is believed to be a disruption in neural communication in the brain, though its exact cause remains unknown.
Strangely, with the release of the DSM-5 in 2013, it shifted to a "positive" or "rule-in" diagnosis (not of exclusion).
This shift requires clinicians to buy into the notion that certain patterns of symptoms, such as intermittency, inconsistency, or incongruence with known neurological diseases, are sufficient to establish FND as a concrete diagnosis, rather than a placeholder for an unknown cause.
I contend this shift is not only reckless but dangerous, as it risks prematurely closing the door on further investigations that could improve quality of life, or even save lives for those effectively orphaned by this diagnosis.
Instead of treating a philosophical interpretation as a concrete diagnosis and discouraging further inquiry by guiding patients into what is effectively a faith-based narrative, clinicians should recognise such cases as unknowns. Failure to do so risks repeating historical patterns of diagnostic overreach and may close down avenues for meaningful investigation.
I hypothesise that Functional Neurological Disorder may prove to be nothing more than a central nervous system reflex to unidentified underlying causes, potentially including rare or currently unrecognised pathologies, rather than a fully fledged disorder in itself, especially given that the frequent comorbidities observed alongside it may not be comorbidities at all, but symptoms of the same underlying process, with the "comorbidity" framing risking masking and functioning as diagnostic shielding rather than true separation of disease entities.
This reflects a confusion of clinical presentation with a discrete disorder or syndrome, treating a shared phenotype as if it represents a single unified condition despite the possibility of diverse underlying biological causes.
I invite you to join me on this website to dig deeper for answers and, perhaps, uncover the real causes.
"I will not be ashamed to say 'I know not.'"
