Abstract
Background
Psychogenic movement disorders (PMDs) represent 2% to 20% of patients with movement disorders. There is a paucity of literature on PMD in children, with most existing literature relating to adults only.
Methods
For this detailed report of 58 patients (33 adults and 25 children) with PMD, history was assessed in the form of disease onset, duration, precipitating factors, diagnosis, and outcome. Movement phenotype was classified in terms of its appearance as tremor, dystonia, myoclonus, chorea, and others. Clinical evaluations were done to document variability, distractibility, and entrainment. Surface electromyography studies were obtained in patients with tremor.
Results
Seven adults and 7 children were classified with “documented” PMD, and 26 adults and 18 children were classified with “clinically established” PMD. Abrupt onset was common in adults (75.75%) and children (68%). The most common precipitating factors were family and social issues (42.42%) in adults and fear of examination (40%) and school‐related issues (24%) in children. Tremor was the most common PMD in both adults and children. The second most common PMD was hemifacial spasm in adults.
Conclusion
The majority of patients had abrupt onset of symptoms, and tremor was the most common form of movement disorder. The second most common PMDs were hemifacial spasm in adults and dystonia and gait abnormality in children. The most common precipitating factors in adults were related to family and social issues; whereas, in children, examination and school‐related issues were most common. Complete improvement was seen in only 405 of patients.
Keywords: dystonia, hemifacial spasm, tremor
Psychogenic movement disorders (PMDs), hysterical movements, conversion reaction manifestations, and dissociative disorders are all terms that might be used by a treating physician for a single disorder, thereby further complicating an already poorly understood disorder.1 Although bradykinetic disorders are less likely than hyperkinetic disorders to have a psychogenic etiology, PMDs can mimic the whole range of organic movement disorders, making them diagnostically and therapeutically challenging for neurologists and psychiatrists.2 There are many clues to the diagnosis on history and examination. Features like abrupt onset, variability, distractibility, possible secondary gain, and comorbid psychiatric illness favor a diagnosis of PMD.3 On physical examination, there may be general clues, and disappearance of the disorder on distraction is most helpful; however, the disorder also may worsen with attention. Fahn and Williams categorized patients with dystonia into 4 levels of certainty based on the likelihood of a psychogenic component, but these categories have been applied to all PMDs.4
Limited data are available on PMD in children, and most of the existing literature relates only to adults.5, 6, 7, 8, 9 Therefore, we undertook this retrospective study of 33 adults and 25 children who were diagnosed with PMD to delineate their clinical characteristics, risk factors, and outcomes.
Patients and Methods
Ours is a detailed report of 58 consecutive patients with PMD (33 adults and 25 children) who attended our Movement Disorder Clinic over the past 2 years and were diagnosed based on criteria described by Fahn and Williams (see Tables S1 and S2).4 All patients were examined, and videos were obtained to record the movement disorders after appropriate informed written consent. We have included videos of adults (n = 7) and children (n = 7) with documented PMD (see Videos S1 and S2). In addition to demographic details, notes were as made of PMD phenomenology, antecedent illnesses, and precipitating factors based on each patient's history, and the final outcomes were analyzed. The final outcome was categorized as improved, partially improved, or not improved. Patients who initially improved but had frequent relapses were classified as partially improved. All efforts were made to contact the referring physician to ascertain the details of previous medical history. Surface electromyography studies were obtained in patients who had tremor to look for entrainment and variability. Patients were treated with counseling, cognitive behavioral therapy, and pharmacotherapy with consultation from the Department of Psychiatry. Seven adults and 2 children were treated with antidepressant medications. Data were analyzed using SPSS software version 13 (SPSS Inc., Cary, NC). Values were expressed as means ± standard deviations and as percentages and ranges. Frequencies between the various groups were compared using the χ2 test, and P values ≤0.05 were considered statistically significant.
Results
Epidemiological Features
Of the 58 patients, 33 (56.89%) were adults, and 25 (43.11%) were children (Table 1). The mean ± standard age was 37.54 ± 14.99 years in adults (range, 19–70 years). The youngest child in our study was 9 years old, and the eldest was 17 years (mean ± standard deviation, 14.12 ± 2.48 years). Among adults, there were slightly more men than women (men:women, 17:16); whereas, among children there were slightly more girls than boys (boys:girls, 12:13). Duration of illness was longer in children (11.90 ± 15.81 months) than in adults (10.22 ± 15.93 months). Seven adults and 7 children had documented PMDs (see Videos S1 and S2), whereas 26 adults (78.79%) and 18 children (62%) had clinically established movement disorders.
Table 1.
Comparison of demographic and clinical characteristics of adults and children with psychogenic movement disorders
| Demographic and Clinical Characteristics | Adults | Children |
|---|---|---|
| Total no. (%) | 33 (56.89) | 25 (43.11) |
| Age, y | ||
| Mean ± SD, y | 37.54 ± 14.99 | 14.12 ± 2.48 |
| Range | 19–70 | 9–17 |
| Males:females | 17:16 | 12:13 |
| Duration: Mean ± SD, mo | 10.22 ± 15.93 | 11.90 ± 15.81 |
| Onset, no. (%) | Abrupt, 25 (75.75); gradual, 8 (24.25) | Abrupt, 17 (68); gradual, 8 (32) |
| Level of certainty, no. (%) | ||
| Documented | Documented, 7 (21.21); clinically established, 26 (78.79) | Documented, 7 (28); clinically established, 18 (62) |
| Comorbidity, no. (%) | Depression, 8 (24.24) | Anxiety, 3 (12) |
| Subdural hematoma, 2 (6.06) | Depression, 2 (8) | |
| Rheumatic heart disease, 1 (3.03) | Epilepsy, 2 (8) | |
| Epilepsy, 1 (3.03) | Psychogenic nonepileptic attack, 1 (4) | |
| Vertigo, 1 (3.03) | Pulmonary tuberculosis, 1 (4) | |
| None, 20 (60.60) | None, 16 (64) | |
| Precipitating event, no. (%) | Family and social issues, 14 (42.42) | Examination, 10 (40) |
| Financial issues, 6 (18.18) | School‐related issues, 6 (24) | |
| Blowing conch, 1 (3.03) | Financial stress, 2 (8) | |
| Fall from bed, 1 (3.03) | Parental issues, 5 (20) | |
| Fever, 1 (3.03) | Fight with friend, 1 (0.04) | |
| Examination, 1 (3.03) | Nepal earthquake, 1 (0.04) | |
| Not known, 9 (27.27) | Not known, 3 (12) | |
| Type of main movement disorder, no. (%) | Tremor, 15 (45.45); hemifacial spasm, 4 (12.12); orofacial dyskinesia, 3 (9.09); dystonia, 3 (9.09); writer's cramp, 2 (6.06); myoclonus, 2 (6.06); choreoathetoid movement, 2 (6.06); gait abnormality, 2 (6.06) | Tremor, 11 (44); dystonia, 4 (16); gait abnormality, 4 (16); psychogenic tics, 3 (12); writer's cramp, 2 (0.08); myoclonus, 2 (0.08); abdominal dyskinesia, 1 (0.04); in 2 patients (Cases 13 and 22) it, was difficult to isolate dominant movement disorder |
| Outcome, no. (%) | Improved, 13 (39.39); partially improved, 8 (24.24); no improvement, 12 (36.36) | Improved, 10 (40); partially improved, 9 (36); no improvement, 6 (24) |
SD, standard deviation.
Clinical Features and Outcome among Adults with PMDs
Tremor was the most common PMD in adults (n = 15; 45.45%) followed by hemifacial spasm (n = 4), orofacial dyskinesias (n = 3), dystonia (n = 3), writer's cramp (n = 2), myoclonus (n = 2), choreoathetoid movements (n = 2), and gait abnormality (n = 2). The most important precipitating factors were related to family and social issues, such as the death of a wife or mother, illness in a father or brother, divorce, dispute with a wife, and fight with a daughter or friend. Financial issues, such as job loss and inability to pay loans, were the second most common precipitating factors. One patient had orofacial dyskinesias and head tremor immediately after blowing a conch. Six months previously, he was asked by his friend to blow the conch regularly to strengthen his facial muscles. He was under tremendous pressure to do it perfectly (see Video S1, Case 3), which led to orofacial dyskinesia. Another patient was a college student who developed writing difficulty just before his graduation examination (see Video S1, Case 6). A trivial fall from bed was the precipitating factor in a 70‐year‐old lady with tremor. She had a history of subdural hematoma 2 years previously and since then had been living in constant fear of getting hurt (see Video S1, Case 7). Thirteen adults (39.39%) experienced complete improvement, 8 (24.24%) had partial improvement, and 12 (36.36%) had no improvement. Complete improvement was observed more frequently in adults with gait disorders (2 of 2 patients; 100%), myoclonus (1 of 2 patients; 50%), writer's cramp (1 of 2 patients; 50%), and tremor (7 of 15 patients; 46.66%). No improvement was observed more frequently in those with choreoathetoid movements (2 of 2 patients; 100%), hemifacial spasm (3 of 4 patients; 75%), orofacial dyskinesia (2 of 3 patients; 66.66%), and dystonia (2 of 3 patients; 66.66%).
Clinical Features and Outcomes among Children with PMD
Tremor was the most common PMD in children (n = 11; 44%), followed by dystonia (n = 4), gait abnormality (n = 4), psychogenic tics (n = 3), writer's cramp (n = 2), myoclonus (n = 2), and abdominal dyskinesias (n = 1). The most common precipitating facto#bib8rs were issues related to examination (40%) and school (24%). Family issues, such as illness in a father, physical abuse, separation, and scolding, led to abnormal movements in 20% of patients. Other precipitating factors were financial stress (8%) and fighting with a friend (4%). One of the children with PMD was a student from Nepal who had abnormal movements immediately after the earthquake in 2015. Psychogenic tics were present only in children, and all had precipitating factors. One child had dystonic tics, which appeared after his father became ill and improved with counseling (see Video S2, Case 5). Another child had abrupt‐onset psychogenic jerks involving his shoulder region and trunk just before his school examination. He also had tremor of all 4 limbs, and his symptoms improved with counseling. Another child who had frequent eye blinking had an abrupt‐onset of symptoms after a fight with his friend. None of these 3 children were able to suppress their jerks, which helped us to differentiate them from organic tics.10 Ten children (40%) experienced complete improvement, 9 (36) had partial improvement in, and 6 (24%) had no improvement. Complete improvement was observed more frequently in children with tics (2 of 3 patients; 66.66%), gait disorders (2 of 4 patients; 50%), myoclonus (1 of 2 patients; 50%), tremor (4 of 9 patients; 44.44%), and abdominal dyskinesia (1 patient case who improved). No improvement was observed more frequently in children with dystonia (2 of 4 patients; 50%) and writer's cramp (1 of 2 patients; 50%).
Comparative Features between Children and Adults with PMD
Most of adults (75.75%) and children (68%) had abrupt‐onset PMD. Underlying comorbid illnesses were present in 13 adults (39.40%) and 9 children (36%). Depression was most common in adults, whereas anxiety was most common in children. Two adult patients also had a history of subdural hematoma. One patient each had a past history of rheumatic heart disease, epilepsy, and vertigo. Among the children, depression was present in 2 patients, 2 had epilepsy, 1 had psychogenic nonepileptic attacks, and 1 had a history of treatment for pulmonary tuberculosis. Precipitating factors were present more in children (88%) than in adults (72.73%). Tremor was the most common PMD observed in adults (45.45%) and children (44%). The second most common PMD phenotypes were hemifacial spasm (12.12%) in adults and dystonia (16%) and gait abnormality (16%) in children. Complete improvement was observed in 13 adults (39.39%) and 10 children (40%); partial improvement was observed in 8 adults (36.36%) and 9 children (36%); and no improvement was observed in 12 adults (36.36%) and 6 children (24%).
Discussion
In this study, 33 adults (56.89%; mean age ± standard deviation, 37.54 ± 14.99 years) and 25 children (43.11%; mean age ± standard deviation, 14.12 ± 2.48 years) were diagnosed with PMD. Only 2 children in our cohort were younger than 10 years, and the youngest was 9 years old. A previous study that described the details of 15 children with PMD included only 2 patients who were younger than 10 years.6 Similarly, in another study in which youngest child was 3 years old, 6 of 50 patients were younger than 10 years.7
Among adults, 51.51% were men; and, among children, 52% were girls. This is contrary to other published studies, in which the majority of patients with PMD were females (range, 61%–91.8%). Even in studies that involved pediatric patients with PMD, there were 3 to 4 times more girls than boys.6 The relatively less representation of both adult women and young girls in our study may stem from the prevalent sociocultural factors in our country, which also was reflected in another Indian study in which no significant difference was observed in the prevalence of PMD among men and women.11
While analyzing the phenomenology of PMD, our results were consistent with most of the related studies. Tremor was the most common PMD in our patient population, accounting for 45.45% of cases among adults and 44% of cases among children. Although most studies have described tremor as the most common PMD in both adults and children, some have observed that dystonia is more frequent than tremors.12 In children, data regarding the most common PMD phenotype are sparse, but tremor, dystonia, myoclonus, and gait disorders all have been described. In a large cohort of 54 children with PMD, Ferrara and Jankovic reported tremor as the most common movement disorder (65%), followed by dystonia, myoclonus, and gait abnormality.5 Canavese and colleagues reported that tremor (36%) was the most common PMD phenotype in 14 children.8 Fernandez‐Alvarez also reported 16 children with PMD and observed that tremor (68%) was the predominant movement disorder, followed by myoclonus.9 Schwingenschuh and colleagues had different observations in 15 children with PMD: those authors reported that dystonia (47%) was the most common PMD, followed by tremor (40%), and gait disorders (13%).6 In 1 Indian study reported by Kamble and colleagues, myoclonus was the most common PMD phenotype, and tremor was observed in only 9% of children.11 Dystonia was the second most common PMD (n = 4; 16%) in our pediatric population along with gait abnormality (n = 4; 16%) and was third most common PMD in our adult population (n = 3; 9.09%). We had 4 adults (all women) with hand‐foot syndrome (HFS), making it the second most common PMD in adults after tremors. No children had HFS. Two adult patients (1 man and 1 woman) had orofacial dyskinesia. Our results bear resemblance to earlier reported cases of psychogenic HFS.13, 14 One group of investigators indicated that approximately 7.4% of all HFS cases referred to them were psychogenic.13 Interestingly, women accounted for almost all cases (15 of 16) in that study. Another study dealing exclusively with psychogenic facial movement disorders observed that 92% of their patients were women.14 Psychogenic facial movement disorders may present in a variety of ways, 1 of which is HFS. Proper understanding of these disorders is necessary, because an incorrect diagnosis may lead to unnecessary investigations and, at times, even botulinum toxin injections and surgical exploration.12
Gait abnormality and dystonia were the second most common PMDs in children (4 patients each; 16%). Schwingenschuh and colleagues reported gait disorder as the third most common movement disorder after dystonia and tremor.6 Myoclonus was seen in 6.06% of the adult population and 8% of the children. Literature review suggest that the percentage of myoclonus in PMD could range anywhere from 8% to 30%.5, 15, 16, 17, 18 Psychogenic tics or jerks were third most common movement disorder observed in children, but none were observed in any of the adults. Two adults and 2 children had psychogenic writer's cramp: The diagnosis was established as functional based on history (abrupt onset in 1 adult and 2 children and a history of definite stressors in all patients) and physical examination (distractibility). In 1 adult patient (Video S1, Case 6), there was immediate improvement with 1 unit of onabotulinum toxin Type A.
The majority of our patients (75.75% of adults and 68% of children) had an abrupt onset to their illness. This is consistent with previous reports in the literature indicating an abrupt onset in between 73% and 83% of patients.5, 11, 14, 19 A study of 54 children with PMD reported that approximately 90% of children presented abruptly.5 A precipitating event, when carefully sought for, can be identified in a great number of patients who have PMD. Studies have reported precipitating factors ranging from 47.9% to as high as 83.7% in adults.11, 19, 20 However, clinicians and researchers should be encouraged to make a phenotype‐specific diagnosis, because phenomenology is the most critical element of the diagnosis, whereas elements in the history or psychopathology may be absent or misleading.21 In our study, precipitating factors were present in 73.73% of adults and 88% of children. It is interesting to note that, in the majority of children (64%), PMD was precipitated by fear of examinations (40%) and school‐related issues (24%). This observation differs from previous studies in which separation from parents, adoption of a sibling, and physical trauma were identified as important precipitating factors.5, 18 Family stressors (19.6%) in adults and school stressors (36.4%) in children also were identified as important precipitating factors in another Indian study.11 Another study indicated that an emotionally stressful life event in 39% of children was responsible for PMD.12 We did not conduct a standardized assessment for any history of sexual abuse, which also sometimes can be a precipitating factor.12, 18
In our study, improvement was initially observed in 21 adults (63.63%) and 19 children (76%); however, 8 adults (24.24%) and 9 children (36%) relapsed after the initial response and were categorized as partially improved. Twelve adults (36.36%) and 6 children (24.24%) showed no signs of improvement in their condition. Studies have reported response rates ranging from 5% to 57%.14, 19, 21, 22, 23 Overall good outcomes were reported by another Indian study in 57.5% patients; in that study, outcomes were better in children (77.3%) compared with adults (49.0%). Correct assessment of the response rate in PMD is challenging considering the high percentage of dropouts among patients with PMD; because, many times, they may not accept the diagnosis.5 One report on 54 children with PMD did not describe the response rates because of a lack of complete follow‐up, which can be a problem when dealing with patients who have PMD.5 In another study of 15 children, 47% recovered fully, 33% improved substantially, and 20% remained chronically and severely disabled.6 Our literature review suggests that, the earlier the presentation, the better are the patient’ chances of recovery.
Conclusion
In this study, males and females had almost equal incidence of PMD, which differs from many of the other described studies. One probable reason for this may be the prevalent gender bias, especially in this part of the country. Also, we observed that, in adults, the most common PMD after tremors was HFS, and it was an all‐female phenomenon. Another interesting observation was the precipitating factors especially in children. The majority of children (64%) in our study had fear of examinations or school‐related issues, which precipitated their PMD. This could be because of the great emphasis, sometimes undue, laid on academic performance by teachers and parents alike in our part of the world.
Author Roles
1. Research Project: A. Conception, B. Organization, C. Execution; 2. Statistical Analysis: A. Design, B. Execution, C. Review and Critique; 3. Manuscript Preparation: A. Writing the First Draft, B. Review and Critique.
S.P: 1A, 1B, 1C, 2A, 2B, 2C, 3A, 3B
A.K.: 1B, 2C, 3A, 3B
Disclosures
Ethical Compliance Statement: We confirm that we have read the Journal's position on issues involved in ethical publication and affirm that this work is consistent with those guidelines.
Funding Sources and Conflict of Interest: The authors report no sources of funding and no conflicts of interest relevant to this work.
Financial Disclosures for the previous 12 months: The authors report no sources of funding and no conflicts of interest.
Supporting information
Videos accompanying this article are available in the supporting information here.
Video S1. Psychogenic movement disorders in adults are shown.
Video S2. Psychogenic movement disorders in children are shown.
Table S1. Demographic and clinical characteristics of adults with psychogenic movement disorders.
Table S2. Demographic and clinical characteristics of children with psychogenic movement disorders.
Relevant disclosures and conflicts of interest are listed at the end of this article.
Supporting information may be found in the online version of this article.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Videos accompanying this article are available in the supporting information here.
Video S1. Psychogenic movement disorders in adults are shown.
Video S2. Psychogenic movement disorders in children are shown.
Table S1. Demographic and clinical characteristics of adults with psychogenic movement disorders.
Table S2. Demographic and clinical characteristics of children with psychogenic movement disorders.