Functional movement disorders are a common clinical concern for neurologists. The principle of "rule-in" diagnosis, which involves demonstrating the difference between voluntary and automatic movement, can be carried through to explanation, triage, and evidence-based multidisciplinary rehabilitation therapy.
In this episode, Gordon Smith, MD, FAAN speaks Jon Stone, PhD, MB, ChB, FRCP, an author of the article "Multidisciplinary Treatment for Functional Movement Disorder" in the Continuum® August 2025 Movement Disorders issue.
Dr. Smith is a Continuum® Audio interviewer and a professor and chair of neurology at Kenneth and Dianne Wright Distinguished Chair in Clinical and Translational Research at Virginia Commonwealth University in Richmond, Virginia.
Dr. Stone is a consultant neurologist and honorary professor of neurology at the Centre for Clinical Brain Sciences at the University of Edinburgh in Edinburgh, United Kingdom.
Additional Resources
Read the article: Multidisciplinary Treatment for Functional Movement Disorder
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Host: @gordonsmithMD
Guest: @jonstoneneuro
Full episode transcript available here
Dr Jones: This is Dr Lyell Jones, Editor-in-Chief of Continuum. This exclusive Continuum Audio interview is available only to you, our subscribers. We hope you enjoy it. Thank you for listening.
Dr Smith: Hello, this is Dr Gordon Smith. Today I've got the great pleasure of interviewing Dr Johnstone about his article on the multidisciplinary treatment for functional neurologic disorder, which he wrote with Dr Alan Carson. This article will appear in the August 2025 Continuum issue on movement disorders. I will say, Jon, that as a Continuum Audio interviewer, I usually take the interviews that come my way, and I'm happy about it. I learn something every time. They're all a lot of fun. But there have been two instances where I go out and actively seek to interview someone, and you are one of them. So, I'm super excited that they allowed me to talk with you today. For those of our listeners who understand or are familiar with FND, Dr Stone is a true luminary and a leader in this, both in clinical care and research. He's also a true humanist. And I have a bit of a bias here, but he was the first awardee of the Ted Burns Humanism in Neurology award, which is a real honor and reflective of your great work. So welcome to the podcast, Jon. Maybe you can introduce yourself to our audience.
Dr Stone: Well, thank you so much, Gordon. It was such a pleasure to get that award, the Ted Burns Award, because Ted was such a great character. I think the spirit of his podcasts is seen in the spirit of these podcasts as well. So, I'm a neurologist in Edinburgh in Scotland. I'm from England originally. I'm very much a general neurologist still. I still work full-time. I do general neurology, acute neurology, and I do two FND clinics a week. I have a research group with Alan Carson, who you mentioned; a very clinical research group, and we've been doing that for about 25 years.
Dr Smith: I really want to hear more about your clinical approach and how you run the clinic, but I wonder if it would be helpful for you to maybe provide a definition. What's the definition of a functional movement disorder? I mean, I think all of us see these patients, but it's actually nice to have a definition.
Dr Stone: You know, that's one of the hardest things to do in any paper on FND. And I'm involved with the FND society, and we're trying to get together a definition. It's very hard to get an overarching definition. But from a movement disorder point of view, I think you're looking at a disorder where there is an impairment of voluntary movement, where you can demonstrate that there is an automatic movement, which is normal in the same movement. I mean, that's a very clumsy way of saying it. Ultimately, it's a disorder that's defined by the clinical features it has; a bit like saying, what is migraine? You know? Or, what is MS? You know, it's very hard to actually say that in a sentence. I think these are disorders of brain function at a very broad level, and particularly with FND disorders, of a sort of higher control of voluntary movement, I would say.
Dr Smith: There's so many pearls in this article and others that you've written. One that I really like is that this isn't a diagnosis of exclusion, that this is an affirmative diagnosis that have clear diagnostic signs. And I wonder if you can talk a little bit about the diagnostic process, arriving at an FND diagnosis for a patient.
Dr Stone: I think this is probably the most important sort of "switch-around" in the last fifteen, twenty years since I've been involved. It's not new information. You know, all of these diagnostic signs were well known in the 19th century; and in fact, many of them were described then as well. But they were kind of lost knowledge, so that by the time we got to the late nineties, this area---which was called conversion disorder then---it was written down. This is a diagnosis of exclusion that you make when you've ruled everything out. But in fact, we have lots of rule in signs, which I hope most listeners are familiar with. So, if you've got someone with a functional tremor, you would do a tremor entrainment test where you do rhythmic movements of your thumb and forefinger, ask the patient to copy them. It's very important that they copy you rather than make their own movements. And see if their tremor stops briefly, or perhaps entrains to the same rhythm that you're making, or perhaps they just can't make the movement. That might be one example. There's many examples for limb weakness and dystonia. There's a whole lot of stuff to learn there, basically, clinical skills.
Dr Smith: You make a really interesting point early on in your article about the importance of the neurological assessment as part of the treatment of the patient. I wonder if you could talk to our listeners about that.
Dr Stone: So, I think, you know, there's a perception that- certainly, there was a perception that that the neurologist is there to make a diagnosis. When I was training, the neurologist was there to tell the patient that they didn't have the kind of neurological problem and to go somewhere else. But in fact, that treatment process, when it goes well, I think begins from the moment you greet the patient in the waiting room, shake their hand, look at them. Things like asking the patient about all their symptoms, being the first doctor who's ever been interested in their, you know, horrendous exhaustion or their dizziness. You know, questions that many patients are aware that doctors often aren't very interested in. These are therapeutic opportunities, you know, as well as just taking the history that enable the patient to feel relaxed. They start thinking, oh, this person's actually interested in me. They're more likely to listen to what you've got to say if they get that feeling off you.
So, I'd spend a lot of time going through physical symptoms. I go through time asking the patient what they do, and the patients will often tell you what they don't do. They say, I used to do this, I used to go running. Okay, you need to know that, but what do they actually do? Because that's such valuable information for their treatment plan. You know, they list a whole lot of TV shows that they really enjoy, they're probably not depressed. So that's kind of useful information. I also spend a lot of time talking to them about what they think is wrong. Be careful, that they can annoy patients, you know. Well, I've come to you because you're going to tell me what's wrong. But what sort of ideas had you had about what was wrong? I need to know so that I can deal with those ideas that you've had. Is there a particular reason that you're in my clinic today? Were you sent here? Was it your idea? Are there particular treatments that you think would really help you? These all set the scene for what's going to come later in terms of your explanation. And, more importantly, your triaging of the patient. Is this somebody where it's the right time to be embarking on treatment, which is a question we don't always ask yourself, I think.
Dr Smith: That's a really great point and kind of segues to my next question, which is- you talked a little bit about this, right? Generally speaking, we have come up with this is a likely diagnosis earlier, midway through the encounter. And you talked a little bit about how to frame the encounter, knowing what's coming up. And then what's coming up is sharing with the patient our opinion. In your article, you point out this should be no different than telling someone they have Parkinson's disease, for instance. What pearls do you have and what pitfalls do you have in how to give the diagnosis? And, you know, a lot of us really weren't trained to do this. What's the right way, and what are the most common land mines that folks step on when they're trying to share this information with patients?
Dr Stone: I've been thinking about this for a long time, and I've come to the conclusion that all we need to do with this disorder is stop being weird. What goes wrong? The main pitfall is that people think, oh God, this is FND, this is something a bit weird. It's in a different box to all of the other things and I have to do something weird. And people end up blurting out things like, well, your scan was normal or, you haven't got epilepsy or, you haven't got Parkinson's disease. That's not what you normally do. It's weird. What you normally do is you take a deep breath and you say, I'm sorry to tell you've got Parkinson's disease or, you have this type of dystonia. That's what you normally say. If you follow the normal- what goes wrong is that people don't follow the normal rules. The patient picks up on this. What's going on here? This doctor's telling me what I don't have and then they're starting to talk about some reason why I've got this, like stress, even though I don't- haven't been told what it is yet. You do the normal rules, give it a name, a name that you're comfortable with, preferably as specific as possible: functional tremor, functional dystonia. And then do what you normally do, which is explain to the patient why you think it's this. So, if someone's got Parkinson's, you say, I think you've got Parkinson's because I noticed that you're walking very slowly and you've got a tremor. And these are typical features of Parkinson. And so, you're talking about the features. This is where I think it's the most useful thing that you can do. And the thing that I do when it goes really well and it's gone badly somewhere else, the thing I probably do best, what was most useful, is showing the patient their signs. I don't know if you do that, Gordon, but it's maybe not something that we're used to doing.
Dr Smith: Wait, maybe you can talk more about that, and maybe, perhaps, give an example? Talk about how that impacts treatment. I was really impressed about the approach to physical therapy, and treatment of patients really leverages the physical examination findings that we're all well-trained to look for. So maybe explore that a little bit.
Dr Stone: Yeah, I think absolutely it does. And I think we've been evolving these thoughts over the last ten or fifteen years. But I started, you know, maybe about twenty years ago, started to show people their tremor entrainment tests. Or their Hoover sign, for example; if you don't know Hoover sign, weakness of hip extension, that comes back to normal when the person's flexing their normal leg, their normal hip. These are sort of diagnostic tricks that we had. Ahen I started writing articles about FND, various senior neurologists said to me, are you sure you should write this stuff down? Patients will find out. I wrote an article with Marc Edwards called "Trick or Treat in Neurology" about fifteen years ago to say that actually, although they're they might seem like tricks, there really are treats for patients because you're bringing the diagnosis into the clinic room. It's not about the normal scan. You can have FND and MS. It's not about the normal scan. It's about what you're seeing in front of you. If you show that patient, yes, you can't move your leg. The more you try, the worse it gets. I can see that. But look, lift up your other leg. Let me show you. Can you see now how strong your leg is? It's such a powerful way of communicating to the patient what's wrong with them diagnostically, giving them that confidence. What it's also doing is showing them the potential for improvement. It's giving them some hope, which they badly need. And, as we'll perhaps talk about, the physio treatment uses that as well because we have to use a different kind of physio for many forms of functional movement disorder, which relies on just glimpsing these little moments of normal function and promoting them, promoting the automatic movement, squashing down that abnormal pattern of voluntary movement that people have got with FND.
Dr Smith: So, maybe we can talk about that now. You know, I've got a bunch of other questions to ask you about mechanism and stuff, but let's talk about the approach to physical therapy because it's such a good lead-in and I always worry that our physical therapists aren't knowledgeable about this. So, maybe some examples, you have some really great ones in the article. And then words of wisdom for us as we're engaging physical therapists who may not be familiar with FND, how to kind of build that competency and relationship with the therapist with whom you work.
Dr Stone: Some of the stuff is the same. Some of the rehabilitation ideas are similar, thinking about boom and bust activity, which is very common in these patients, or grading activity. That's similar, but some of them are really different. So, if you have a patient with a stroke, the physiotherapist might be very used to getting that person to think and look at their leg to try and help them move, which is part of their rehabilitation. In FND, that makes things worse. That's what's happening in Hoover sign and tremor entrainment sign. Attention towards the limb is making it worse. But if the patient's on board with the diagnosis and understands it, they'll also see what you need to do, then, in the physio is actively use distraction in a very transparent way and say to the patient, look, I think if I get you to do that movement, and I'll film you, I think your movement's going to look better. Wouldn't that be great if we could demonstrate that? And the patient says, yeah, that would be great.
We're kind of actively using distraction. We're doing things that would seem a bit strange for someone with other forms of movement disorder. So, the patients, for example, with functional gait disorders who you discover can jog quite well on a treadmill. In fact, that's another diagnostic test. Or they can walk backwards, or they can dance or pretend that they're ice skating, and they have much more fluid movements because their ice skating program in their brain is not corrupted, but their normal walking program is. So, can you then turn ice skating or jogging into normal walking? It's not that complicated, I think. The basic ideas are pretty simple, but it does require some creativity from whoever's doing the therapy because you have to use what the patient's into. So, if the patient used to be a dancer- we had a patient who was a, she was really into ballet dancing. Her ballet was great, but her walking was terrible. So, they used ballet to help her walk again. And that's incredibly satisfying for the therapist as well. So, if you have a therapist who's not sure, there are consensus recommendations. There are videos. One really good success often makes a therapist want to do that again and think, oh, that's interesting. I really helped that patient get better.
Dr Smith: For a long time, this has been framed as a mental health issue, conversion disorder, and maybe we can talk a little bit about early life of trauma as a risk factor. But, you know, listening to you talk, it sounds like a brain network problem. Even the word "functional", to me, it seems a little judgmental. I don't know if this is the best term, but is this really a network problem?
Dr Stone: The word "functional", for most neurologists, sounds judgmental because of what you associate it with. If you think about what the word actually is, it's- it does what it says on the tin. There's a disordered brain function. I mean, it's not a great word. It's the least worst term, in my view. And yes, of course it's a brain network problem, because what other organ is it going to be? You know, that's gone wrong? When software brains go wrong, they go wrong in networks. But I think we have to be careful not to swing that pendulum too far to the other side because the problem here, when we say asking the question, is this a mental health problem or a neurological one, we're just asking the wrong question. We're asking a question that makes no sense. However you try and answer that, you're going to get a stupid answer because the question doesn't make sense. We shouldn't have those categories. It's one organ. And what's so fascinating about FND---and I hope what can incite your sort of curiosity about it---is this disorder which defies this categorization. You see some patients with it, they say, oh, they've got a brain network disorder. Then you meet another patient who was sexually abused for five years by their uncle when they were nine, between nine and fourteen; they developed an incredibly strong dissociative threat response into that experience. They have crippling anxiety, PTSD, interpersonal problems, and their FND is sort of somehow a part of that; part of that experience that they've had. So, to ignore that or to deny or dismiss psychological, psychiatric aspects, is just as bad and just as much a mistake as to dismiss the kind of neurological aspects as well.
Dr Smith: I wonder if this would be a good time to go back and talk a little bit about a concept that I found really interesting, and that is FND as a prodromal syndrome before a different neurological problem. So, for instance, FND prodromal to Parkinson's disease. Can you talk to us a little bit about that? I mean, obviously I was familiar with the fact that patients who have nonepileptic seizurelike events often have epileptic seizures, but the idea of FND ahead of Parkinson's was new to me.
Dr Stone: So, this is definitely a thing that happens. It's interesting because previously, perhaps, if you saw someone who was referred with a functional tremor---this has happened to me and my colleagues. They send me some with a functional tremor. By the time I see them, it's obvious they've got Parkinson's because it's been a little gap. But it turns out that the diagnosis of functional tremor was wrong. It was just that they've developed that in the prodrome of Parkinson's disease. And if you think about it, it's what you'd expect, really, especially with Parkinson's disease. We know people develop anxiety in the prodrome of Parkinson's for ten, fifteen years before it's part of the prodrome. Anxiety is a very strong risk factor for FND, and they're already developing abnormalities in their brain predisposing them to tremor. So, you put those two things together, why wouldn't people get FND? It is interesting to think about how that's the opposite of seizures, because most people with comorbidity of functional seizures and epilepsy, 99% of the time the epilepsy came first. They had the experience of an epileptic seizure, which is frightening, which evokes strong threat response and has somehow then led to a recapitulation of that experience in a functional seizure. So yeah, it's really interesting how these disorders overlap. We're seeing something similar in early MS where, I think, there's a slight excess of functional symptoms; but as the disease progresses, they often become less, actually.
Dr Smith: What is the prognosis with the types of physical therapy? And we haven't really talked about psychological therapy, but what's the success rate? And then what's the relapse rate or risk?
Dr Stone: Well, it does depend who they're seeing, because I think---as you said---you're finding difficult to get people in your institution who you feel are comfortable with this. Well, that's a real problem. You know, you want your therapists to know about this condition, so that matters. But I think with a team with a multidisciplinary approach, which might include psychological therapy, physio, OT, I think the message is you can get really good outcomes. You don't want to oversell this to patients, because these treatments are not that good yet. You can get spectacular outcomes. And of course, people always show the videos of those. But in published studies, what you're seeing is that most studies of- case series of rehabilitation, people generally improve. And I think it's reasonable to say to a patient, that we have these treatments, there's a good chance it's going to help you. I can't guarantee it's going to help you. It's going to take a lot of work and this is something we have to do together. So, this is not something you're going to do to the patient, they're going to do it with you. Which is why it's so important to find out, hey, do they agree with you with the diagnosis? And check they do. And is it the right time? It's like when someone needs to lose weight or change any sort of behavior that they've just become ingrained. It's not easy to do. So, I don't know if that helps answer the question.
Dr Smith: No, that's great. And you actually got right where I was wanting to go next, which is the idea of timing and acceptance. You brought this up earlier on, right? So, sometimes patients are excited and accepting of having an affirmative diagnosis, but sometimes there's some resistance. How do you manage the situation where you're making this diagnosis, but a patient's resistant to it? Maybe they're fixating on a different disease they think they have, or for whatever reason. How do you handle that in terms of initiating therapy of the overall diagnostic process?
Dr Stone: We should, you know, respect people's rights to have whatever views they want about what's wrong with them. And I don't see my job as- I'm not there to change everyone's mind, but I think my job is to present the information to them in a kind of neutral way and say, look, here it is. This is what I think. My experience is, if you do that, most people are willing to listen. There are a few who are not, but most people are. And most of the time when it goes wrong, I have to say it's us and not the patients. But I think you do need to find out if they can have some hope. You can't do rehabilitation without hope, really. That's what you're looking for. I sometimes say to patients, where are you at with this? You know, I know this is a really hard thing to get your head around, you've never heard of it before. It's your own brain going wrong. I know that's weird. How much do you agree with it on a scale of naught to ten? Are you ten like completely agreeing, zero definitely don't? I might say, are you about a three? You know, just to make it easy for them to say, no, I really don't agree with you. Patients are often reluctant to tell you exactly what they're thinking. So, make it easy for them to disagree and then see where they're at. If they're about seven, say, that's good. But you know, it'd be great if you were nine or ten because this is going to be hard. It's painful and difficult, and you need to know that you're not damaging your body. Those sort of conversations are helpful. And even more importantly, is it the right time? Because again, if you explore that with people, if a single mother with four kids and, you know, huge debts and- you know, it's going to be very difficult for them to engage with rehab. So, you have to be realistic about whether it's the right time, too; but keep that hope going regardless.
Dr Smith: So, Jon, there's so many things I want to talk to you about, but maybe rather than let me drive it, let me ask you, what's the most important thing that our listeners need to know that I haven't asked you about?
Dr Stone: Oh God. I think when people come and visit me, they sometimes, let's go and see this guy who does a lot of FND, and surely, it'll be so easy for him, you know? And I think some of the feedback I've had from visitors is, it's been helpful to watch, to see that it's difficult for me too. You know, this is quite hard work. Patients have lots of things to talk about. Often you don't have enough time to do it in. It's a complicated scenario that you're unravelling. So, it's okay if you find it difficult work. Personally, I think it's very rewarding work, and it's worth doing. It's worth spending the time. I think you only need to have a few patients where they've improved. And sometimes that encounter with the neurologist made a huge difference. Think about whether that is worth it. You know, if you do that with five patients and one or two of them have that amazing, really good response, well, that's probably worth it. It's worth getting out of bed in the morning. I think reflecting on, is this something you want to do and put time and effort into, is worthwhile because I recognize it is challenging at times, and that's okay.
Dr Smith: That's a great number needed to treat, five or six.
Dr Stone: Exactly. I think it's probably less than that, but…
Dr Smith: You're being conservative.
Dr Stone: I think deliberately pessimistic; but I think it's more like two or three, yeah.
Dr Smith: Let me ask one other question. There's so much more for our listeners in the article. This should be required reading, in my opinion. I think that of most Continuum, but this, I really truly mean it. But I think you've probably inspired a lot of listeners, right? What's the next step? We have a general or comprehensive neurologist working in a community practice who's inspired and wants to engage in the proactive care of the FND patients they see. What's the next step or advice you have for them as they embark on this? It strikes me, like- and I think you said this in the article, it's hard work and it's hard to do by yourself. So, what's the advice for someone to kind of get started?
Dr Stone: Yeah, find some friends pretty quick. Though, yeah, your own enthusiasm can take you a long way, you know, especially with we've got much better resources than we have. But it can only take you so far. It's really particularly important, I think, to find somebody, a psychiatrist or psychologist, you can share patients with and have help with. In Edinburgh, that's been very important. I've done all this work with the neuropsychiatrist, Alan Carson. It might be difficult to do that, but just find someone, send them an easy patient, talk to them, teach them some of this stuff about how to manage FND. It turns out it's not that different to what they're already doing. You know, the management of functional seizures, for example, is- or episodic functional movement disorders is very close to managing panic disorder in terms of the principles. If you know a bit about that, you can encourage people around you. And then therapists just love seeing these patients. So, yeah, you can build up slowly, but don't- try not to do it all on your own, I would say. There's a risk of burnout there.
Dr Smith: Well, Dr Stone, thank you. You don't disappoint. This has really been a fantastic conversation. I really very much appreciate it.
Dr Stone: That's great, Gordon. Thanks so much for your time, yeah.
Dr Smith: Well, listeners, again, today I've had the great pleasure of interviewing Dr Jon Stone about his article on the multidisciplinary treatment for functional neurologic disorder, which he wrote with Dr Alan Carson. This article appears in the August 2025 Continuum issue on movement disorders. Please be sure to check out Continuum Audio episodes from this and other issues. And listeners, thank you once again for joining us today.
Dr Monteith: This is Dr Teshamae Monteith, Associate Editor of Continuum Audio. We hope you've enjoyed this subscriber-exclusive interview. Thank you for listening.
