There is no evidence for functional neurological disorder, it is simply a hypothesis. As a diagnostic category it is essentially a "god of the gaps" construct.

There is no evidence for functional neurological disorder, it is simply a hypothesis. As a diagnostic category it is essentially a "god of the gaps" construct. Remember also that the name is a re-branding of what used to be called conversion disorder (previously known as hysteria), that was found to be an acceptable term to patients.[1] It's heavily published on and widely accepted as valid by neurologists, but that does not make it true. The concept with FND is that there is no identifiable structural pathology, but that the neural circuits are dysfunctional, and that this can be fixed with things like cognitive behavioural therapy. This is typically framed to the patient as "the hardware is completely OK, there's just a problem with the software." (As most of this audience would recognise there is very little overlap between how brains work and how computers work.) However, more advanced imaging techniques, such as 7T MRI are now showing structural abnormalities in these patients, which is a pretty fundamental problem for the above hypothesis. An attempt to rationalise this by FND proponents is made here.[2] A recent example involves a 10yo child who developed a movement disorder following Covid.[3] Typically these would be diagnosed as functional movement disorder [4][5][6] and psychological therapy advised. However this group showed that in fact it was due to a neuroimmune pathology, with auto-antibodies forming that targeted some portion of the basal ganglia. The patient recovered completely with immunosuppression. [1] https://www.bmj.com/content/325/7378/1449 https://www.bmj.com/content/325/7378/1449 [2] https://neurosymptoms.org/en/faq-2/can-people-with-fnd-have-changes-to-the-structure-of-their-brain-too/ https://neurosymptoms.org/en/faq-2/can-people-with-fnd-have-... [3] https://link.springer.com/article/10.1007/s00415-023-11853-5 https://link.springer.com/article/10.1007/s00415-023-11853-5 [4] https://movementdisorders.onlinelibrary.wiley.com/doi/10.1002/mds.28778 https://movementdisorders.onlinelibrary.wiley.com/doi/10.100... [5] https://cp.neurology.org/content/11/5/e686 https://cp.neurology.org/content/11/5/e686 [6] https://adc.bmj.com/content/106/5/420 https://adc.bmj.com/content/106/5/420