One of the oldest and most well understood conditions in neuropsychiatry is the “functional neurologic disorder” or FND. It is actually a group of disorders where the brain begins to misbehave, often causing a symptom that is evaluated by neurology such as weakness, numbness, shaking, or convulsions. It is different from other neurologic conditions because it is treated primarily with psychiatric medications and psychotherapeutic techniques. While my biases are strong that fields of psychiatry and neurology should have never separated, the fact is that they have and wishing for better coordination of care in our current medical model won’t change that fact. Because of this, the functional neurologic disorder is very well understood, easily identified, very treatable, and very few patients actually receive proper treatment for it. 

Historically, it has gone by many names, of which the most stigma is attached to the term “conversion disorder”. Stigma aside, conversion disorder may be the most accurate and encompassing. In psychological and psychiatric theory, there is some sort of psychological condition (anxiety, depression, PTSD) that when untreated can manifest as (or convert into) a physical symptom. This may seem reductionistic or “non-scientific” but the theory led to many different very effective treatment approaches utilizing psychotherapy. While we have learned more and more about the changes to the brain in someone with these conditions, the only treatments that consistently work are psychotherapy with or without psychiatric medications. 

It is very important to understand a few key concepts related to FND. 

1. FND symptoms are exceedingly common. The second most common cause of convulsions in an epilepsy clinic is the functional neurologic disorder with convulsions. The fourth most common cause of tremor in a movement disorder clinic is the functional neurologic disorder with abnormal movements. 

2. FND often exists in combination with another neurologic condition, where it is better termed a “functional overlay”. This is most commonly seen in neuroinflammatory disorders like MS, chronic pain conditions, and sometimes even in Epilepsy. 

3. FND is not a “rule out diagnosis” meaning that there are specific symptom features that would almost always occur in FND and would make other diagnoses very unlikely. While a neurologist may do a lot of tests to “rule out” epilepsy, FND seizures (also called non-epileptic seizures) typically have features that cannot occur in epileptic seizures. 

4. FND is most definitely not when a patient is “faking” a symptom (also called malingering). On the contrary, studies have shown the exact opposite changes in brain activity in someone faking a symptom and someone with the FND symptom. 

5. While FND is treated with psychotherapeutic tools, many psychologists and therapists are very uncomfortable treating it. They will often focus on symptoms related to anxiety or depression and mostly ignore the FND complaint. 

Identifying and treating FND is an easy process for a neurologist, a psychiatrist, and a therapist who all work together very closely, but that doesn’t happen very often. Unfortunately, it falls on the patient to coordinate their own care, ferrying messages from one provider back to the other. If the patient doesn’t have access to a psychiatrist, psychologist, or therapist who will treat them, they tend to see many neurologists until they find one that they feel takes them seriously. This usually means that the neurologist diagnoses a different neurologic condition, though the symptom doesn’t respond to the treatment for the new inappropriate diagnosis. These patients also get very confused since a doctor might say, “this could be lupus” but never explains when lupus is ruled out. I’ve met FND patients who will report a dozen diagnoses given to them over the years, some of which are inevitably fatal in childhood, and many of which can’t technically occur in the same individual. 

This is not to say that a second opinion is a bad idea. I typically encourage patients to get a second opinion, but they should find one general neurologist that they trust to help them understand the second opinion and to discuss options going forward. It is debatable if a tenth opinion is helpful, but I have definitely helped patients who had seen nine other neurologists before. Typically though, the problem was the lack of a primary neurologist that they trusted. The majority of the neurologists said “the tests came back normal, establish with psychiatry and follow up if things don’t improve” and the patient heard “Nothing is wrong with you, you need a psychiatrist, now get out of my office”. 

At any rate, most neurologists are very capable of diagnosing a functional neurologic disorder, and they know that the treatment involves various forms of therapy (physical therapy, occupational therapy, and psychotherapy) as well as psychiatric medication management. When they make the diagnosis and recommend the patient see a therapist, this is not meant to place the responsibility elsewhere any more than telling a patient to establish with an endocrinologist if the neurologist diagnoses an atypical thyroid disease. The question is how to get a patient into see a psychiatrist, physical therapist, and psychotherapist who will treat them. The neurologist should also remain available in case symptoms change or new questions arise about the problem so that the patient doesn’t have to start from scratch with a new neurologist each time. 

In the following articles I will outline some of the various presentations of a functional neurologic disorder, the way medications are chosen, and the techniques that a psychotherapist can use to help treat them. If you would like to discuss your functional neurologic disorder diagnosis, don’t hesitate to reach out for a consultation.