Functional neurological disorders: mechanisms and treatment

Human-mouse chimeric brain models constructed from iPSC-derived brain cells: Applications and challenges

The establishment of reliable human brain models is pivotal for elucidating specific disease mechanisms and facilitating the discovery of novel therapeutic strategies for human brain disorders. Human induced pluripotent stem cell (iPSC) exhibit remarkable self-renewal capabilities and can differentiate into specialized cell types. This makes them a valuable cell source for xenogeneic or allogeneic transplantation. Human-mouse chimeric brain models constructed from iPSC-derived brain cells have emerged as valuable tools for modeling human brain diseases and exploring potential therapeutic strategies for brain disorders. Moreover, the integration and functionality of grafted stem cells has been effectively assessed using these models. Therefore, this review provides a comprehensive overview of recent progress in differentiating human iPSC into various highly specialized types of brain cells. This review evaluates the characteristics and functions of the human-mouse chimeric brain model. We highlight its potential roles in brain function and its ability to reconstruct neural circuitry in vivo. Additionally, we elucidate factors that influence the integration and differentiation of human iPSC-derived brain cells in vivo. This review further sought to provide suitable research models for cell transplantation therapy. These research models provide new insights into neuropsychiatric disorders, infectious diseases, and brain injuries, thereby advancing related clinical and academic research.

Physiotherapy management of functional movement disorders: the patient perspective

PURPOSE

People with functional movement disorders (FMD) are commonly seen in neurology clinics. Despite a recent increase in research, no standardised treatment pathway across the UK exists. Currently only a few qualitative studies in FMD with a focus on psychological aspects and diagnosis have been published. This study aimed to understand people with FMD perceptions of their physiotherapy treatment.

METHOD

Qualitative web-based interviews were conducted with seven participants and an interpretive phenomenological approach was used to identify themes from the data.

RESULTS

Four themes were identified; 1) my brain, mind and body are all me, 2) physiotherapy; what helps and what doesn't, 3) what recovery is to me, and 4) barriers to treatment. Participants desired a combination of psychological and physical approaches, which were holistic, individualised, and delivered by experienced physiotherapists. Limited availability and funding of specialist treatments were barriers to recovery.

CONCLUSION

Holistic management combining psychological and physiological systems seems to be crucial for effective management of FMD. Large variations in physiotherapy treatment exist across the UK. It is hoped that increasing the understanding, amongst healthcare professionals will lead to the development of timely and appropriate pathways for patients that otherwise find themselves lost between medical specialities.IMPLICATIONS FOR REHABILITATIONPatients report more positive experiences when a combined and detailed psychological and physiological explanation to their symptoms is given.An individualised approach working with the patient on activities they find challenging is more preferable than group exercise or impairment based (e.g., strengthening/stretching) treatments.Having a physiotherapist who is experienced in treating functional movement disorders or prepared to learn and understand them helped with adherence to treatment.

A Critical Examination of the Clinical Diagnosis of Functional Tic-like Behaviors

BACKGROUND

Since the COVID-19 pandemic, movement disorder clinics have seen an increase in patients with an unusual type of tic-like symptoms: young adults with abrupt onset complex behaviors. It was quickly suspected that these patients suffered from functional neurological symptoms, later named Functional Tic-Like Behaviors (FTLB). Subsequent research on the differential diagnosis between FTLB and tics has been substantial and led to the development of diagnostic checklists.

OBJECTIVES

We conducted a theoretical reappraisal of the FTLB literature to clarify the validity of the concept and its diagnostic implications.

METHODS

This paper addresses several key aspects of the current FTLB literature: circular reasoning, the complications of the FTLB phenomenology and demographics, the impact of FTLB on tic literature at large, and issues with alignment of the FTLB concept with the diagnostic criteria for functional disorders.

RESULTS

The clinical approach to FTLB might involve circular reasoning due to a lack of clinical benchmarks. The FTLB phenomenology and demographics may need more work to ensure a lack of bias and a proper description of this patient group including a clear distinction from tics. The impact of the FTLB discussion on the wider literature needs consideration. The validation of positive signs may help with both these endeavors and pave way to the inclusion of FTLB within psychiatric classification systems. Furthermore, the coexistence of FTLB and tics within the same patient needs to be addressed.

CONCLUSION

More research may be needed to fully establish the diagnosis of FTLB and differentiate it from tics.

Comprehensive Insights into Metastasis-Associated Spinal Cord Compression: Pathophysiology, Diagnosis, Treatment, and Prognosis: A State-of-the-Art Systematic Review

Background: Spinal cord compression is a formidable complication of advanced cancer, and clinicians of copious specialities often have to encounter significant complex challenges in terms of diagnosis, management, and prognosis. Metastatic lesions from cancer are a common cause of spinal cord compression, affecting a substantial portion of oncology patients, and only in the US has the percentage risen to 10%. Acute metastasis-correlated spinal cord compression poses a considerable clinical challenge, necessitating timely diagnosis and intervention to prevent neurological deficits. Clinical presentation is often non-specific, emphasizing the importance of thorough evaluation and appropriate differential diagnosis. Diagnostic workup involves various imaging modalities and laboratory studies to confirm the diagnosis and assess the extent of compression. Treatment strategies focus on pain management and preserving spinal cord function without significantly increasing patient life expectancy, while multidisciplinary approaches are often required for optimal outcomes. Prognosis depends on several factors, highlighting the importance of early intervention. We provide an up-to-date overview of acute spinal cord compression in metastases, accentuating the importance of comprehensive management strategies. Objectives: This paper extensively explores the pathophysiology, clinical presentation, diagnostic strategies, treatment modalities, and prognosis associated with spinal cord metastases. Materials and Methods: A systematic literature review was conducted in accordance with the PRISMA guidelines. Conclusions: We aim to help healthcare professionals make informed clinical decisions when treating patients with spinal cord metastases by synthesizing current evidence and clinical insights.

Increased Cyclic Adenosine Monophosphate Responsive Element is Closely Associated with the Pathogenesis of Drug-resistant Epilepsy

BACKGROUND

Drug-resistant epilepsy (DRE) is a refractory neurological disorder. There is ample evidence that suggest that γ-aminobutyric acid-a (GABAA) receptors could be one of the mechanisms responsible for the development of drug resistance in epilepsy. It is also known that the cAMP response element binding protein (CREB) plays a possible key role in the transcriptional regulation of GABAA.

OBJECTIVE

This study explores the role of CREB in the development of DRE and the effect of CREB on GABA-related receptors in DRE.

METHODS

The CREB expression was increased or decreased in the hippocampus of normal rats by lentiviral transfection, who then underwent the lithium-pilocarpine-induced epilepsy model. Phenobarbital (PB) sodium and carbamazepine (CBZ) were used to select a drug-resistant epileptic model. The expression levels of GABAA receptor α1, β2, and γ2 subunits and CREB protein were measured in the rat hippocampus by western blot and fluorescent quantitative PCR.

RESULTS

The frequency and duration of seizures increased in the overexpression group compared to that in the control group. In addition, the severity, frequency, and duration of seizures decreased in the group with decreased expression. The hippocampus analysis of the expression levels of the CREB protein and CREB mRNA yielded similar findings. Altering the CREB protein expression in the rat hippocampus could negatively regulate the expression and transcript levels of GABAA receptors α1, β2, and γ2, suggesting that CREB may serve as a potential target for the development of treatment protocols and drugs for epilepsy.

CONCLUSION

Our study shows that enhanced CREB expression promotes the development of DRE and negatively regulates GABAA receptor levels and that the inhibition of CREB expression may reduce the incidence of DRE.

Costs of adult functional neurological disorders at a tertiary hospital in central South Africa

Background

Functional neurological disorders (FND) lead to increased care requirements and costs, negatively impacting healthcare budgets. Healthcare expenditure in FND has escalated beyond other neurologic disorders during the past decade.

Objectives

To assess inpatient costs in adults admitted to the neurology ward at Universitas Academic Hospital (UAH) in central South Africa.

Methods

A retrospective observational study with a comparative component was conducted on patients admitted during 2018 and 2019. All FND cases (n = 29) and a systematic sample of other neurological disorders were included in the comparison group (n = 29). Data were obtained from the Meditech billing system and clinical records.

Results

FND patients accounted for 5.5% of 530 admissions in the neurology ward during the study period. No significant differences regarding daily median cost, age categories, gender or medical comorbidity were observed between FND and the comparison group. However, the length of stay was significantly shorter for the FND patients (median of four versus eight days), translating to approximately half the total costs of patients admitted for other neurological disorders.

Conclusion

The daily median cost was similar for FND and other neurology-related admissions. The lower overall inpatient costs for FND patients were only related to significantly shorter durations of stay, which may reflect new diagnostic approaches resulting from changes in the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5) diagnostic criteria. The prevalence of FND was similar to those reported in previous studies conducted at neurology clinics.

Contribution

The study contributes towards better understanding the prevalence and cost of FND in local neurology inpatient care settings.

Physical Rehabilitation of Motor Functional Neurological Disorders: A Narrative Review

Functional Neurological Disorders (FNDs) are one of the most common and disabling neurological disorders, affecting approximately 10-30% of patients in neurology clinics. FNDs manifest as a range of motor, sensory, and cognitive symptoms that are not explained by organic disease. This narrative review aims to assess the current state of knowledge in physical-based rehabilitation for motor/movement FNDs in the adult population, with the goal of improving research and medical care for this patient population. To ensure optimal outcomes for patients, it is critical to consider several domains pertaining to FNDs, including which field of discipline they should belong to, how to investigate and test, methods for rating outcome measures, and optimal courses of treatment. In the past, FNDs were primarily treated with psychiatric and psychological interventions. However, recent literature supports the inclusion of physical rehabilitation in the treatment of FNDs. Specifically, physical-based approaches tailored to FNDs have shown promising results. This review utilized a comprehensive search of multiple databases and inclusion criteria to identify relevant studies.

The neurobiology of functional neurological disorders characterised by impaired awareness

We review the neurobiology of Functional Neurological Disorders (FND), i.e., neurological disorders not explained by currently identifiable histopathological processes, in order to focus on those characterised by impaired awareness (functionally impaired awareness disorders, FIAD), and especially, on the paradigmatic case of Resignation Syndrome (RS). We thus provide an improved more integrated theory of FIAD, able to guide both research priorities and the diagnostic formulation of FIAD. We systematically address the diverse spectrum of clinical presentations of FND with impaired awareness, and offer a new framework for understanding FIAD. We find that unraveling the historical development of neurobiological theory of FIAD is of paramount importance for its current understanding. Then, we integrate contemporary clinical material in order to contextualise the neurobiology of FIAD within social, cultural, and psychological perspectives. We thus review neuro-computational insights in FND in general, to arrive at a more coherent account of FIAD. FIAD may be based on maladaptive predictive coding, shaped by stress, attention, uncertainty, and, ultimately, neurally encoded beliefs and their updates. We also critically appraise arguments in support of and against such Bayesian models. Finally, we discuss implications of our theoretical account and provide pointers towards an improved clinical diagnostic formulation of FIAD. We suggest directions for future research towards a more unified theory on which future interventions and management strategies could be based, as effective treatments and clinical trial evidence remain limited.

The clinical management of functional neurological disorder: A scoping review of the literature

OBJECTIVE

To date, there have been no reviews bringing together evidence on the clinical management of functional neurological disorder (FND) and patients', caregivers', and healthcare workers' experiences. This review provides an overview of the literature focused on the clinical management of FND.

METHODS

Four databases were searched, and a consultation exercise was conducted to retrieve relevant records dated from September 2010 to September 2020. Articles documenting diagnostic methods, treatments or interventions, or the experiences and perspectives of patients and healthcare workers in the clinical management of FND were included.

RESULTS

In total, 2756 records were retrieved, with 162 included in this review. The diagnostic methods reported predominantly included positive clinical signs, v-EEG and EEG. Psychological treatments and medication were the most reported treatments. Mixed findings of the effectiveness of CBT were found. Haloperidol, physiotherapy and scripted diagnosis were found to be effective in reducing FND symptoms. Several facilitators and barriers for patients accessing treatment for FND were reported.

CONCLUSION

The literature describing the clinical management for FND has increased considerably in recent times. A wide variety of diagnostic tools and treatments and interventions were found, with more focus being placed on tests that confirm a diagnosis than 'rule-out' tests. The main treatment type found in this review was medication. This review revealed that there is a lack of high-quality evidence and reflects the need for official clinical guidelines for FND, providing healthcare workers and patients the support needed to navigate the process to diagnose and manage FND.

Efficacy of a 5-day, intensive, multidisciplinary, outpatient physical and occupational therapy protocol in the treatment of functional movement disorders: A retrospective study

BACKGROUND

The use of rehabilitation services has been shown to be beneficial for patients with functional movement disorders (FMD). However, there is great variability in the type of rehabilitation services utilized. In the present study we aimed at determining the efficacy of an intense outpatient physical rehabilitation program as a treatment modality for patients with FMD.

METHODS

Eighteen participants underwent treatment in a specialized outpatient rehabilitation program utilizing a multidisciplinary approach for the treatment of FMD. Participants completed a series of tests on day one and day five of the program.

RESULTS

Results indicated statistically significant improvements in all but one motor and gait outcomes in patients with functional movement disorders treated with physical rehabilitation.

CONCLUSION

These results provide support for the continued use of physical and occupational therapy for functional movement disorder patients. Further research is needed to fully validate these findings and there remains a need for further study into multidisciplinary approaches that may be even more efficacious.

Olfactory Drug Aerosol Delivery with Acoustic Radiation

Nose-to-brain (N2B) drug delivery is a new approach to neurological disorder therapy as medications can bypass the blood-brain barrier and directly enter the brain. However, the delivery efficiency to the olfactory region using the conventional delivery method is impractically low because of the region’s secluded position in a convoluted nasal cavity. In this study, the acoustic radiation force was explored as an N2B delivery alternative in a wide frequency range of 10–100,000 Hz at an increment of 50 Hz. Numerical simulations of the particle deposition in the olfactory region of four nasal configurations were performed using COMSOL. Frequency analysis of the nasal cavities revealed that eigenfrequencies were often associated with a specific region with narrow passages and some eigenfrequencies exhibited an amendable pressure field to the olfactory region. Transient particle tracking was conducted with an acoustic inlet at 1 Pa, and a frequency spectrum of 10–100,000 Hz was imposed on the airflow, which carried the particles with acoustic radiation forces. It was observed that by increasing the pulsating wave frequency at the nostrils, the olfactory delivery efficiency reached a maximum in the range 11–15 kHz and decreased after that. The correlation of the olfactory delivery efficiency and instantaneous values of other parameters such as acoustic velocity and pressure in the frequency domain was examined.

Psychological interventions for treating functional motor symptoms: A systematic scoping review of the literature

Functional Movement Disorders (FMD) can be identified by limb weakness, gait disorders, or involuntary movements which are inconsistent with a neurological diagnosis. Despite the prevalence of such symptoms, there has been little consensus on models for treatment. This scoping review set out to identify the literature exploring the efficacy of psychological interventions for the treatment of FMD, either as a stand-alone intervention or as part of a multi-disciplinary team approach. Studies set in an adult inpatient and outpatient setting were considered for inclusion. The final review consisted of 33 papers; 13 reviewing psychological treatments only, and 20 reviewing multidisciplinary approaches that included a psychological intervention. This review of the literature reaffirms the inconsistency across treatment for FMD, although identifies a trend towards an MDT approach in recent years. The review also identifies areas where consistency in methodology may be beneficial in future research, in order to improve the validity of results for greater comparison of treatments. There are promising outcomes that support the continued investigation focused on an interdisciplinary, collaborative approach to care, for the reduction of symptoms.

Understanding, Recognizing, and Managing Functional Speech Disorders: Current Thinking Illustrated With a Case Series

PURPOSE

Functional speech disorders (FSDs), a subtype of functional neurological disorders, are distinguishable from neurogenic motor speech disorders based on their clinical features, clinical course, and response to treatment. However, their differential diagnosis and management can be challenging. FSDs are not well understood, but growing evidence suggests a biopsychosocial basis distinct from structural lesions that cause neurogenic motor speech disorders.

METHOD AND RESULTS

Following an overview of FSDs, four patients are described to illustrate the range of clinical manifestations, biopsychosocial contexts, and responses to treatment of FSDs. The path to differential diagnosis is discussed, with particular attention to positive features that led to the FSD diagnosis. Approaches to education, counseling, and management are discussed.

CONCLUSIONS

This case series demonstrates that FSDs can present with a variety of manifestations including dysfluencies, articulation errors, dysphonia, rate and prosodic abnormalities, and combinations of disruptions in speech subsystems. FSDs may present in the context of known recent or remote physical or psychosocial trauma or, as in many cases, in the absence of an identifiable triggering event. FSDs are recognizable by positive clinical features and should not be considered a diagnosis of exclusion. With appropriate identification, counseling, and treatment, FSDs may resolve, sometimes rapidly; in some cases, treatment may be prolonged or ineffective.

Diagnostic pitfalls in functional neurological disorders

The diagnosis of functional neurological disorders is a major challenge in neurologist practice. Some clinical strategies can facilitate the recognition of functional disorders, but several pitfalls make their diagnosis difficult. Here we highlight the following points of attention during evaluation of patients with functional disorder: not all bizarre behavior is functional; not every event triggered by an emotional factor is a functional disorder; not every topographic incongruity is a functional disorder; patients may present functional and organic symptoms at the same time; psychiatric comorbid condition is not always evident in the history of a functional disorder; problematic communication at the time of diagnosis can compromise treatment and prognosis. In conclusion, we emphasize that special attention to these possible pitfalls facilitate the correct diagnosis and management of functional neurological disorders.

Diagnosis of Functional Weakness and Functional Gait Disorders in Children and Adolescents

Functional neurological disorder is neurological dysfunction not primarily explained by pathophysiologic or structural abnormalities and can present in children and adolescents with limb weakness, gait abnormality, non-epileptic seizures or sensory changes. In this review article we focus primarily on the diagnosis of functional limb weakness and functional gait disorders, and how to differentiate functional neurological disorders from structural or pathologic neurological presentations of weakness or gait disturbance. Detailed history and attentive observation of a patient outside of the formal neurological examination can be pertinent to identifying inconsistency and incongruency in keeping with functional neurological presentations. Understanding of structural and physiologic neurological pathology is required to identify non-anatomical and non-pathological features consistent with a diagnosis of functional neurological disorder. Diagnosis is made on recognition of positive clinical features of a functional disorder on examination and is not based primarily on exclusion of a pathologic neurological disorder. Specific tests can be performed to elicit pathognomonic findings supportive of a diagnosis of functional limb weakness and gait disorders.

Neurological and neuropsychological adverse effects of SARS-CoV-2 vaccines - where do we stand?

The devastating characteristic of COVID-19 pandemic calls for immediate and effective solutions to tackle it. Vaccines seem to be the only promising and effective way to fight against the novel coronavirus - even against new mutated variants. Because of the rapid development and distribution of numerous COVID-19 vaccines in different platforms, meticulous evaluation of vaccines' safety is more critical than ever - especially given the fact that most of the candidates have not completed the clinical phase. Therefore, to optimize the vaccines' safety and efficacy, it is highly important to carefully report and scientifically discuss the serious adverse effects following vaccination. In this respect, we discuss different neurological and neuropsychological adverse effects of COVID-19 vaccines including demyelinating diseases, Bell's palsy (BP), cerebrovascular complications, seizures, functional neurological disorders (FNDs), and some other rare adverse events, and hypothetical mechanisms which can lead to the reported side effects. Given the fact that the incidence of such events are rare and most of them are treatable, the current review aims to shed light on how much the relationship between COVID-19 vaccines and these complications can be reliable and provide an insight for future studies with much more meticulous methodologies to discuss the possible correlational or causal relationship between these complications and COVID-19 vaccines and elucidate whether or not the neurological side effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines can count as a considerable threat to public health.

Repetitive transcranial magnetic stimulation for patients with functional paralysis: a randomized controlled study

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) has been proposed to treat functional neurological disorders. Here, we aim to assess the efficacy of rTMS to treat functional paralysis in a controlled randomized trial.

METHODS

Patients received 2 sessions of active or sham 0.25 Hz rTMS (60 stimuli each), with a one-day interval, applied over the motor cortex contralateral to the paralysis. The primary outcome was the number of patients with an increase in motor score between baseline and after the second rTMS session, rated by two investigators blinded to the treatment allocation. Secondary outcomes were changes in global and fine motor scores between groups after rTMS, and occurrence of adverse events.

RESULTS

Sixty-two patients (46 female; mean [SD] age, 35.2 [13.9] years) were enrolled and randomized. Thirteen out of 32 (41%) and 11/30 (37%) patients had increased motor strength after active or sham rTMS, respectively (p=0.80). Changes in both global and fine motor scores after rTMS relative to baseline were also not significantly different between treatment groups (median difference in the global motor score 0.62 [0.83] and 0.37 [0.61], and fine motor scores 0.12 [0.18] and 0.08 [0.11], in active and sham rTMS groups, respectively, p=0.14). We observed six serious adverse events, consisting of 3 cephalalgia in the active group and 2 cephalalgia and 1 asthenia in the sham group.

CONCLUSIONS

Two sessions of sham or active low frequency rTMS were effective to improve functional paralysis, suggesting a placebo effect of this non-invasive brain stimulation technique.

Management of Functional Neurological Disorders (FND): Experience from a Swiss FND Clinic

Functional neurological disorder (FND) represent a common disorder with significant socio-economic impact. In this context and alongside recent new neuroscientific insights, FND attracts a growing interest both in clinical practice and academic activities. New international recommendation and expert opinions suggest that therapy of FND should be a tailored multidisciplinary management involving the neurologist, the physiotherapist, and in most cases the psychotherapist/psychiatrist. A first decisive step is the establishment of a definitive diagnosis, based on the presence of clinical positive signs during neurological assessment together with a clear communication and explanation of the diagnosis by the neurologist. A second important step is based on individual therapeutic sessions, involving different disciplines (neurology and psychotherapy or neurology and physiotherapy). Comorbidities, such as pain or fatigue and psychiatric comorbidities (anxiety, depression, dissociation etc.) should be carefully evaluated, as they need an individualized treatment path. New FND clinics have been created worldwide over the last decades to offer such multidisciplinary settings and this article will present the experience of a first Swiss FND clinic created in 2016. The aim is to highlight in the form of a narrative review the current literature supporting the usefulness and importance of FND clinics, by reviewing the latest evidence on multidisciplinary interventions in FND.

A Systematic Review and Meta-analysis of the Effect of Oral Exercises on Masticatory Function

The aim of the current systematic review was to summarize and to evaluate the available information on the effectiveness of oral exercise in improving the masticatory function of people ≥18 y. Electronic databases (Medline, Embase, CENTRAL) and gray literatures were searched (up to December 2020) for relevant randomized and nonrandomized controlled clinical trials. Two reviewers independently conducted the study selection, data extraction, and quality assessments. Meta-analysis was conducted for the comparison of bite force and masticatory performance using mean difference (MD) and standardized mean difference (SMD), respectively. GRADE (Grading of Recommendations Assessment, Development, and Evaluation) assessment was adopted for collective grading of the overall body of evidence. Of the 1,576 records identified, 18 studies (21 articles) were included in the analysis. Results of meta-analysis indicated that oral exercise could significantly improve the mean bite force of the participants (parallel comparison: MD, 41.2; 95% CI, 11.6-70.7, P = 0.006; longitudinal comparison: MD, 126.5; 95% CI, 105.2-144.9, P < 0.001). However, the improvement in masticatory performance was not significant (parallel comparison: SMD, 0.11; 95% CI, -0.20 to 0.42, P = 0.48; longitudinal comparison: SMD, 0.4; 95% CI, -0.11 to 0.91, P = 0.13). Results of meta-regression showed that greater improvements in bite force can be achieved among younger adults and with more intensive exercise. Chewing exercise is the most effective oral exercise, followed by clenching exercise, while simple oral exercise may not have a significant effect. Based on the results of the meta-analysis and GRADE assessment, a weak recommendation for people with declined masticatory function to practice oral exercise is made.

Genetically Encoded Fluorescent Biosensors for Biomedical Applications

One of the challenges of modern biology and medicine is to visualize biomolecules in their natural environment, in real-time and in a non-invasive fashion, so as to gain insight into their physiological behavior and highlight alterations in pathological settings, which will enable to devise appropriate therapeutic strategies. Genetically encoded fluorescent biosensors constitute a class of imaging agents that enable visualization of biological processes and events directly in situ, preserving the native biological context and providing detailed insight into their localization and dynamics in cells. Real-time monitoring of drug action in a specific cellular compartment, organ, or tissue type; the ability to screen at the single-cell resolution; and the elimination of false-positive results caused by low drug bioavailability that is not detected by in vitro testing methods are a few of the obvious benefits of using genetically encoded fluorescent biosensors in drug screening. This review summarizes results of the studies that have been conducted in the last years toward the fabrication of genetically encoded fluorescent biosensors for biomedical applications with a comprehensive discussion on the challenges, future trends, and potential inputs needed for improving them.

Metacognitive Performance on Memory and Visuospatial Tasks in Functional Cognitive Disorder

Functional Cognitive Disorder (FCD) is a common diagnosis at the memory clinic. FCD is characterised by significant self-reported cognitive symptoms in the absence of external evidence of cognitive dysfunction. A potential explanation for this is a deficit in metacognition, the process by which we internally judge our own abilities. Here we investigated differences in accuracy, confidence, and metacognition between people with FCD (N = 20), neurodegenerative mild cognitive impairment (nMCI; N = 14), and healthy controls (N = 23). The groups were assessed on forced choice memory and perceptual tasks, with trial by trial confidence ratings. FCD and nMCI participants showed lower accuracy on the memory task (means FCD 63.65%, nMCI 63.96%, HC 71.22%), with a significant difference between the FCD and HC groups after controlling for age and sex. There were no between-group differences in memory task confidence (means FCD 3.19, nMCI 3.59, HC 3.71). The FCD group showed greater confidence when longer time was allowed on the memory task. No between group differences in perceptual task accuracy (means FCD 63.97%, nMCI 64.50%, FCD 65.86%) or confidence (means FCD 3.71, nMCI 3.43, HC 3.88) were found. No differences in metacognitive efficacy emerged between the groups, either on the memory or perceptual task (Memory Meta-d'/d':FCD 0.63, nMCI 0.94 HC 0.85; Perceptual Meta-d',d': FCD 0.50, nMCI 0.51, HC 0.72). Participants showed greater metacognitive efficacy on the memory task compared to the perceptual task. The difficulties experienced by people with FCD do not appear to be due to metacognitive deficits. Their performance was similar to people with nMCI over aspects of the memory tasks, which suggests that the primary issue may lie with memory encoding or retrieval, rather than with their judgement of performance accuracy.

How do ophthalmologists manage functional visual symptoms? A UK survey of ophthalmologists' experience

BACKGROUND/AIMS

Functional visual symptoms are relatively common symptoms seen by ophthalmologists. However, there are no consensus guidelines on ophthalmological management of this condition, and there is a paucity of knowledge about the collective challenges experienced in treating patients with functional visual symptoms. In order to establish an ophthalmological perspective on this condition, we undertook the first national survey of experience, knowledge and management of functional visual symptoms amongst ophthalmologists.

METHODS

An online survey was disseminated to ophthalmologists in the UK via all Royal College of Ophthalmology college tutors.

RESULTS

One hundred nineteen ophthalmologists completed the survey. Functional visual symptoms accounted for 3% of all new referrals. Forty per cent of respondents felt they had a good understanding of functional visual symptoms. Two-thirds reported a need for further training in this area. Respondents estimated two-thirds of patients' symptoms improved, but a third experienced severe or extreme disability. Following diagnosis, a minority of patients were referred to mental health or neurology services. The majority of respondents described difficulty discussing psychological factors, with a lack of time or space in a clinic preventing a holistic approach. Free text comments highlighted a lack of access to dedicated psychological support for patients.

CONCLUSION

Functional visual symptoms are disabling and are seen relatively frequently by ophthalmologists. This preliminary survey suggests that care pathways for patients with functional visual symptoms could be optimised. Fostering links between ophthalmology and existing services with expertise in functional disorders could improve patient care and clinician education and ultimately encourage research in this area.

The Aversion Function of the Limbic Dopaminergic Neurons and Their Roles in Functional Neurological Disorders

The Freudian theory of conversion suggested that the major symptoms of functional neurological disorders (FNDs) are due to internal conflicts at motivation, especially at the sex drive or libido. FND patients might behave properly at rewarding situations, but they do not know how to behave at aversive situations. Sex drive is the major source of dopamine (DA) release in the limbic area; however, the neural mechanism involved in FND is not clear. Dopaminergic (DAergic) neurons have been shown to play a key role in processing motivation-related information. Recently, DAergic neurons are found to be involved in reward-related prediction error, as well as the prediction of aversive information. Therefore, it is suggested that DA might change the rewarding reactions to aversive reactions at internal conflicts of FND. So DAergic neurons in the limbic areas might induce two major motivational functions: reward and aversion at internal conflicts. This article reviewed the recent advances on studies about DAergic neurons involved in aversive stimulus processing at internal conflicts and summarizes several neural pathways, including four limbic system brain regions, which are involved in the processing of aversion. Then the article discussed the vital function of these neural circuits in addictive behavior, depression treatment, and FNDs. In all, this review provided a prospect for future research on the aversion function of limbic system DA neurons and the therapy of FNDs.

Management of functional communication, swallowing, cough and related disorders: consensus recommendations for speech and language therapy

Communication problems (eg, dysphonia, dysfluency and language and articulation disorders), swallowing disorders (dysphagia and globus), cough and upper airway symptoms, resulting from functional neurological disorder (FND), are commonly encountered by speech and language professionals. However, there are few descriptions in the literature of the most effective practical management approaches. This consensus document aims to provide recommendations for assessment and intervention that are relevant to both adults and young people. An international panel of speech and language professionals with expertise in FND were approached to take part. Participants responded individually by email to a set of key questions regarding best practice for assessment and interventions. Next, a video conference was held in which participants discussed and debated the answers to these key questions, aiming to achieve consensus on each issue. Drafts of the collated consensus recommendations were circulated until consensus was achieved. FND should be diagnosed on the basis of positive clinical features. Speech and language therapy for FND should address illness beliefs, self-directed attention and abnormal movement patterns through a process of education, symptomatic treatment and cognitive behavioural therapy within a supportive therapeutic environment. We provide specific examples of these strategies for different symptoms. Speech and language professionals have a key role in the management of people with communication and related symptoms of FND. It is intended that these expert recommendations serve as both a practical toolkit and a starting point for further research into evidence-based treatments.

Implicit motor imagery using laterality recognition in functional movement disorders

Functional movement disorder (FMD) presents as disabling motor symptoms that cannot be explained by organic processes. Despite the lack of lesion or known central nervous system dysfunction, distortion in sensorimotor processing in movement generation and execution is often observed. A person's capacity to judge laterality of a body part requires processing of sensorimotor information. This prospective observational study compared reaction time (RT) and accuracy (ACC) of hand laterality recognition between 30 people diagnosed with FMD and 30 age-matched healthy control participants. The association of RT and ACC with severity of FMD as measured by the Simplified Functional Movement Disorders Rating Scale (SFMDRS) was also explored. RT was on average 0.6 s slower (95% CI 0.4 - 0.8 s, p < 0.001) in patients with FMD (mean 2.2 s, standard deviation (SD) 0.5) than controls (mean 1.7 s, SD 0.3). ACC was on average 8.9% lower (95% CI -15.7 - -2.2, p = 0.01) in patients with FMD (mean 79.6%, SD 16.6) than controls (mean 88.5%, SD 8.1). When adjusted for SFMDRS using robust regression, RT was 0.3 s slower (95% CI 0.01 - 0.5, p = 0.04) in cases than in controls, but ACC was no longer different between groups. There was a moderate negative correlation between RT and ACC in FMD patients (ρ -0.58, p < 0.001 but not in controls (ρ -0.26, p = 0.17). People with FMD had significantly slower RT and lower ACC compared to the control group. These results provide new insights into underlying sensorimotor processing deficits in those with FMD.

Inpatient Treatment of Functional Neurological Disorder: A Scoping Review

BACKGROUND

The aim of this scoping review is to describe the characteristics of patients requiring admission to hospital for functional neurological disorder (FND), assess interventions provided, and evaluate outcomes in the context of acute hospital presentation or elective admission with chronic symptoms (>3 months).

METHODS

A scoping review was performed. Included articles described adult patients admitted with FND to an inpatient care setting. Articles focusing on psychogenic non-epileptic attacks (PNEA) were excluded.

RESULTS

The search strategy identified 1963 citations. A total of 34 articles met inclusion criteria, with 458 patients (66% female) described. The pooled mean age of patients in all studies was 40.6 years. Eleven studies described patients with acute presentation, and 16 studies described patients with chronic FND symptoms admitted to the hospital. Motor symptoms were most common. Interventions were most commonly physiotherapy and psychotherapy. Most studies reported partial or complete resolution of symptoms.

CONCLUSIONS

This scoping review summarizes the literature on the characteristics of patients admitted to the hospital, both with acute and chronic symptoms, for inpatient treatment of FND. When comparing patients with acute to those with chronic symptoms, we found that acute presentations were older (46.9 vs. 43.7 years) and had a higher representation of men (33% vs. 30%). Those presenting with chronic symptoms were more likely to not improve or relapse. We postulate that early diagnosis and inpatient rehabilitation could have a positive impact on outcomes for patients with FND.

Functional neurological disorders presenting as emergencies to secondary care

BACKGROUND

Functional neurological disorders (FND) represent a significant proportion of presentations to outpatient adult neurology services. There is little information relating to patients presenting to acute inpatient care.

METHODS

We identified patients presenting as acute admissions with FND to Christchurch Hospital, Christchurch, New Zealand, from 2016 to 2018. We analyzed relevant demographic and clinical data from electronic records and measured incidence of presentation to secondary care and healthcare utilization.

RESULTS

One hundred sixty-two patients presented on 173 occasions with FND, representing 9% of all admissions to the neurology service during the 3-year study period. The mean age was 40 (SD 17) years, 111 (69%) patients were female and the median length of stay was 3 (IQR 2-4) days. A total of 92 computed tomography brain scans, 77 magnetic resonance imaging brain scans and 42 electroencephalograms were carried out. On 22 (13%) occasions, patients were referred for outpatient psychological therapy. In the 3 years prior to each patient's last presentation in the study period, these 162 patients had a total of 671 presentations to the emergency department. Healthcare demand did not decrease after the index admission. The rate of acute inpatient admission for FND was 10 per 100,000 per year for the total Christchurch Hospital catchment, 6/100,000/year in rural areas, and 11/100,000/year in urban areas.

CONCLUSION

FND represented almost 1 in 10 acute neurology admissions with significant inpatient healthcare resource utilization.

Use of dual-flow bioreactor to develop a simplified model of nervous-cardiovascular systems crosstalk: A preliminary assessment

Chronic conditions requiring long-term rehabilitation therapies, such as hypertension, stroke, or cancer, involve complex interactions between various systems/organs of the body and mutual influences, thus implicating a multiorgan approach. The dual-flow IVTech LiveBox2 bioreactor is a recently developed inter-connected dynamic cell culture model able to mimic organ crosstalk, since cells belonging to different organs can be connected and grown under flow conditions in a more physiological environment. This study aims to setup for the first time a 2-way connected culture of human neuroblastoma cells, SH-SY5Y, and Human Coronary Artery Smooth Muscle Cells, HCASMC through a dual-flow IVTech LiveBox2 bioreactor, in order to represent a simplified model of nervous-cardiovascular systems crosstalk, possibly relevant for the above-mentioned diseases. The system was tested by treating the cells with 10nM angiotensin II (AngII) inducing PKCβII/HuR/VEGF pathway activation, since AngII and PKCβII/HuR/VEGF pathway are relevant in cardiovascular and neuroscience research. Three different conditions were applied: 1- HCASMC and SH-SY5Y separately seeded in petri dishes (static condition); 2- the two cell lines separately seeded under flow (dynamic condition); 3- the two lines, seeded in dynamic conditions, connected, each maintaining its own medium, with a membrane as interface for biohumoral changes between the two mediums, and then treated. We detected that only in condition 3 there was a synergic AngII-dependent VEGF production in SH-SY5Y cells coupled to an AngII-dependent PKCβII/HuR/VEGF pathway activation in HCASMC, consistent with the observed physiological response in vivo. HCASMC response to AngII seems therefore to be generated by/derived from the reciprocal cell crosstalk under the dynamic inter-connection ensured by the dual flow LiveBox 2 bioreactor. This system can represent a useful tool for studying the crosstalk between organs, helpful for instance in rehabilitation research or when investigating chronic diseases; further, it offers the advantageous opportunity of cultivating each cell line in its own medium, thus mimicking, at least in part, distinct tissue milieu.

Multidisciplinary inpatient rehabilitation for Functional Movement Disorders: A prospective study with long term follow up

INTRODUCTION

Functional Movement Disorders (FMDs) are challenging to treat. We assessed the effect of multidisciplinary inpatient rehabilitation, involving motor retraining, psychotherapy and psychotropic medication on FMD patient function and maintenance of improvement after one year.

METHODS

FMD patients in a movement disorders clinic were referred for inpatient rehabilitation. Baseline, discharge and one year follow-up measures included: Clinical Global Impression (CGI-severity, CGI-change); Depression and Somatic Symptom Scale (DSSS); Generalized Anxiety Disorder-7 (GAD-7); Patient Health Questionnaire-9 (PHQ-9); Post-traumatic stress disorder check-list for DSM-5 (PCL-5). Outcomes were analyzed with non-parametric models.

RESULTS

Seventeen patients completed rehabilitation. Thirteen completed one-year follow-up. Median CGI-severity was "markedly ill." At discharge, movement disorder improved in 93% (median CGI-change = 2, "much improved") as assessed by neurologist and patient. Psychiatrist ratings showed improvement among 86.7%; physiatrist and psychologist ratings were 66.7% and 53.3%, respectively. Symptoms improved on DSSS (Wilcoxon Z = -2.914, p ≤ 0.004); GAD-7 (Z = -3.045, p ≤ 0.002); PHQ-9 (Z = -3.415, p ≤ 0.01) but not PCL-5 (Z = -1.506, p = 0.132). At 1 year, 54% maintained at least minimal improvement by neurologist rating and 77% by patient rating (median CGI-change = 3, "minimally improved"). Improvement was not maintained for DSSS (Wilcoxon Z = -0.385. p = 0.701), GAD-7 (Z = -0.943, p = 0.357) or PHQ-9 (Z = -0.55, p = 0.582).

CONCLUSIONS

Multidisciplinary inpatient rehabilitation improved FMD patient function, depression, anxiety and somatic symptoms. One-year follow-up demonstrated minimal sustained improvement and worsening psychopathology, reflecting chronic debility despite initial rehabilitative success.

What Is the Role of a Specialist Assessment Clinic for FND? Lessons From Three National Referral Centers

OBJECTIVE

A growing interest in functional neurological disorders (FND) has led to the development of specialized clinics. This study aimed to better understand the structure and role of such clinics.

METHODS

Data were retrospectively collected from clinical records at three national referral centers, two specifically for motor FND and one for FND in general. Data were for 492 consecutive patients referred over a 9- to 15-month period: 100 from the United Kingdom clinic, 302 from the Swiss clinic, and 90 from the Canadian clinic. Data included symptom subtype and duration, comorbid pain and fatigue, disability, and treatment recommendations.

RESULTS

The mean age of the 492 patients was 44 years, and most (73%) were female. Most had a prolonged motor FND (mean symptom duration of 6 years); 35% were not working because of ill health, 26% received disability benefits, and up to 38% required a care giver for personal care. In the Swiss cohort, 39% were given a diagnosis of another somatic symptom disorder rather than an FND diagnosis. Pain was common in the United Kingdom (79%) and Canada (56%), as was fatigue (48% and 47%, respectively). Most patients (61%) were offered physiotherapy; referral to neuropsychiatry or psychology differed across centers (32%-100%).

CONCLUSIONS

FND specialty clinics have an important role in ensuring correct diagnosis and appropriate treatment. Most patients with motor FND require specialized neurophysiotherapy. Patients readily accepted an integrated neuropsychiatric approach. Close collaboration between FND clinics and acute neurology facilities might improve early detection of FND and could improve outcomes.

Functional Stroke Symptoms: A Narrative Review and Conceptual Model

Stroke services have been reconfigured in recent years to facilitate early intervention. Throughout stroke settings, some patients present with functional symptoms that cannot be attributed to a structural cause. Emphasis on fast diagnosis and treatment means that a proportion of patients entering the care pathway present with functional symptoms that mimic stroke or have functional symptoms in addition to vascular stroke. There is limited understanding of mechanisms underlying functional stroke symptoms, how the treatment of such patients should be managed, and no referral pathway or treatment. Predisposing factors vary between individuals, and symptoms are heterogeneous: onset can be acute or insidious, and duration can be short-lived or chronic in the context of new or recurrent illness cognitions and behaviors. This article proposes a conceptual model of functional symptoms identified in stroke services and some hypotheses based on a narrative review of the functional neurological disorder literature. Predisposing factors may include illness experiences, stressors, and chronic autonomic nervous system arousal. Following the onset of distressing symptoms, perpetuating factors may include implicit cognitive processes, classical and operant conditioning, illness beliefs, and behavioral responses, which could form the basis of treatment targets. The proposed model will inform the development of theory-based interventions as well as a functional stroke care pathway.

Hedonicity in functional motor disorders: a chemosensory study assessing taste

The aim of this study was to explore hedonicity to basic tastes in patients with functional motor disorders (FMDs) that are often associated with impairment in emotional processing. We recruited 20 FMD patients and 24 healthy subjects, matched for age and sex. Subjects were asked to rate the hedonic sensation (i.e., pleasant, neutral, and unpleasant) on a - 10 to +10 scale to the four basic tastes (sweet, sour, salty, and bitter) at different concentrations, and neutral stimuli (i.e., no taste stimulation) by means of the Taste Strips Test. Anxiety, depression, and alexithymia were assessed. FMD patients rated the highest concentration of sweet taste (6.7 ± 2.6) as significantly more pleasant than controls (4.7 ± 2.5, p = 0.03), and the neutral stimuli significantly more unpleasant (patients: - 0.7 ± 0.4, controls: 0.1 ± 0.4, p = 0.013). Hedonic ratings were not correlated to anxiety, depression, or alexithymia scores. Hedonic response to taste is altered in FMD patients. This preliminary finding might result from abnormal interaction between sensory processing and emotional valence.

[The classification of dissociative disorders and bodily distress disorder: A comparison of ICD-10 and ICD-11]

The classification of dissociative disorders and bodily distress disorder: A comparison of ICD-10 and ICD-11 Abstract. There have been some major changes in the classification of dissociative disorders in the transition from ICD-10 to ICD-11. One important revision is the elimination of the term "conversion disorder" from the grouping title as well as the omission of any appraisal of the patient´s behavior or motivation. In ICD-11, the dissociative neurological symptom disorder has gained in importance, reflected in its presentation in the first place of this category. In contrast to ICD-10, dissociative identity disorder (multiple personality disorder) has become a single disorder. Bodily distress disorder has replaced the somatoform disorders of ICD-10 and now includes neurasthenia, while hypochondria was eliminated from this category altogether. Bodily distress disorder is defined by distinct psychological features such as extreme distress but not by the presence or absence of medical findings.

Transcranial magnetic stimulation over the right temporoparietal junction influences the sense of agency in healthy humans

Background

The sense of agency is an important aspect of motor control. Impaired sense of agency has been linked to several medical conditions, including schizophrenia and functional neurological disorders. A complex brain network subserves the sense of agency, and the right temporoparietal junction is one of its main nodes. In this paper, we tested whether transcranial magnetic stimulation over the right temporoparietal junction elicited behavioural changes in the sense of agency.

Methods

In experiment 1, 15 healthy participants performed a behavioural task during functional MRI, with the goal of localizing the area relevant for the sense of agency in the right temporoparietal junction. In the task, the movement of a cursor (controlled by the participants) was artificially manipulated, and the sense of agency was either diminished (turbulence) or enhanced (magic). In experiment 2, we applied transcranial magnetic stimulation in 20 healthy participants in a sham-controlled, crossover trial with excitatory, inhibitory or sham (vertex) stimulation. We measured the summary agency score, an indicator of the sense of agency (lower values correspond to diminished sense of agency).

Results

Experiment 1 revealed a peak of activation during agency manipulation in the right temporoparietal junction (Montreal Neurological Institute coordinates x, y, z: 68, -26, 34). Experiment 2 showed that inhibition of the right temporoparietal junction significantly reduced the summary agency score in both turbulence (from -14.4 ± 11.4% to -22.5 ± 8.9%), and magic (from -0.7 ± 5.8% to -4.4 ± 4.4%).

Limitations

We found no excitatory effects, possibly because of a ceiling effect (because healthy participants have a normal sense of agency) or noneffectiveness of the excitatory protocol.

Conclusion

Our experiments showed that the network subserving the sense of agency was amenable to neuromodulation in healthy participants. This sets the ground for further research in patients with impaired sense of agency. Clinical trial identification: DRKS00012992 (German clinical trials registry).

Functional stroke symptoms: A prospective observational case series

OBJECTIVE

Functional symptoms are a common mimic of stroke in acute stroke settings, but there are no guidelines on how to manage such patients and scant research on their clinical profile. We explore the presentation of patients with functional stroke symptoms at admission and 2-month follow-up.

METHODS

We conducted a prospective observational study across four SE London acute stroke units, with two-month follow-up. Demographic information, clinical data and GP attendances were recorded. Patients completed self-report measures: Cognitive Behavioural Responses Questionnaire short version, Brief Illness Perception Questionnaire, Hospital Anxiety and Depression Scale, Work and Social Adjustment Scale and Short Form Health Survey.

RESULTS

Fifty-six patients (mean age: 50.9 years) were recruited at baseline; 40 with isolated functional symptoms, the remaining functional symptoms in addition to stroke. Thirty-one completed self-report follow-up measures. Of 56 participants, 63% were female. Patients presented symptoms across modalities, with unilateral and limb weakness the most frequent. There was inconsistent and ambiguous recording of symptoms on medical records. Approximately 40% of patients reported levels of anxiety and depression above the threshold indicating a probable diagnosis. Higher anxiety was associated with greater resting or all-or-nothing behaviours, embarrassment avoidance and symptom focussing on the CBRQ. Only SF-36 physical functioning improved at follow-up. Less than 50% who responded at follow-up were accessing a treatment, though 82% had ongoing symptoms.

CONCLUSION

Patients with functional symptoms in stroke settings report substantial distress, associated with cognitive-behavioural responses to symptoms. Follow-up data suggest recovery can be slow, indicating access to supportive interventions should be improved.

Shared demographics and comorbidities in different functional motor disorders

INTRODUCTION

Functional motor disorders are often delineated according to the dominant motor symptom. In a large cohort, we aimed to find if there were differences in demographics, mode of onset, pain, fatigue, depression and anxiety and levels of physical functioning, quality of life and social adjustment between patients with different dominant motor symptoms.

METHODS

Baseline data from the Self-Help and Education on the Internet for Functional Motor Disorders Trial was used. Patients were divided into dominant motor symptom groups based on the diagnosis of the referring neurologist. Data on the above topics were collected by means of an online questionnaire and compared between groups using parametric and nonparametric statistics.

RESULTS

In 160 patients a dominant motor symptom could be determined, 31 had tremor, 45 myoclonus, 23 dystonia, 30 paresis, 31 gait disorder. No statistical differences between groups were detected for demographics, mode of onset and severity of pain, fatigue, depression and anxiety. Physical functioning was worse in the gait disorder group (median 20, IQR 25) compared to tremor (50 (55), p = 0.002) and myoclonus (50 (52), p = 0.001). Work and social adjustment was less impaired in the myoclonus group (median 20, IQR 18) compared to gait disorder (median 30, IQR18, p < 0.001) and paresis (28, IQR 10, p = 0.001). Self-report showed large overlap in motor symptoms.

CONCLUSION

No differences were detected between groups of functional motor symptoms, regarding demographics, mode of onset, depression, anxiety, pain and fatigue. The large overlap in symptoms contributes to the hypothesis of shared underlying mechanisms of functional motor disorders.

Abnormal postural behavior in patients with functional movement disorders during exposure to stress

BACKGROUND

Patients affected by functional (psychogenic) movement disorders (FMD) have abnormal processing of stress responses. However, little is known about the influence of this abnormal stress processing on automatic motor defense behavior, such as freeze response. Our aim was thus to investigate stress-induced postural motor responses in FMD.

METHODS

Nine FMD patients and thirteen healthy controls were engaged in the Trier Social Stress Test, while we measured the movement of their body by means of accelerometers and gyroscopes attached to the thorax. Standard deviation of thorax acceleration, reflecting the variability of movement amplitude (body sway), was compared across groups over time in a 2 × 2 ANOVA design. Higuchi's fractal dimension (HFD), reflecting the complexity of movement pattern over time, was also analyzed. Salivary cortisol and α-amylase samples were collected before and after the experiment, as stress biomarkers. Pearson's correlation coefficients were calculated between these biomarkers and movement parameters.

RESULTS

A significant interaction effect was found, showing that healthy controls reduced their thorax sway over time during exposure to stress (from 0.027 ± 0.010 m/s² to 0.023 ± 0.008 m/s², effect size of Cohen's d = 0.95), whereas patients with FMD did not. This change in body sway in controls over time negatively correlated with salivary cortisol values (ρ = -0.67, p = 0.012). A significant group effect revealed that FMD patients had an overall larger body sway (0.038 ± 0.013 m/s²) compared to controls (0.025 ± 0.009 m/s² - effect size of Cohen's d = 1.29) and a lower HFD (1.602 ± 0.071) than controls (1.710 ± 0.078 - Cohen's d = 1.43).

CONCLUSIONS

Patients with FMD failed to show a reduction of body sway over time, i.e., freeze response observed in the controls, thus suggesting an impairment in the automatic defense behavior. Moreover, our analysis found a lower complexity of movement (HFD) in FMD, which deserves future research in order to verify whether this could represent a characteristic trait of the disorder.

Positive clinical signs in neurological diseases - An observational study

Many patients with organic neurological disease have symptoms and signs that are unexplained by their disease condition. We attempted to explore the prevalence of positive clinical signs in patients with various organic neurological diseases. We performed a prospective uncontrolled observational study on the presence of 7 positive signs in adults with various organic neurological diseases that were admitted to our tertiary care hospital. This observation was performed during their neurological examination in those who provided consent, could comprehend and lacked terminal illness or profound weakness that limited their ability to perform these tasks. We dichotomized them into two groups based on the presence of these signs. Out of 190 patients that were evaluated between 2014 and 2015, 37 patients had at least one positive sign. On univariate analysis: young age, female gender, prior anxiety, history of childhood abuse, identification of sensory deficits on examination and lack of imaging correlation with clinical localization were identified as risk factors for these positive signs. On multivariate analysis, anxiety (OR 2.88, 95% CI 1.11-7.49, p = 0.03) and presence of sensory deficits on examination (OR 5.81, 95% CI 2.36-14.32, p ≤ 0.001) were associated with these positive signs. Positive signs are common in patients with organic neurological diseases that have anxiety or sensory deficits and may imply a component of functional overlay. Large studies are required to understand its pathophysiology and impact on future outcomes.

Complex regional pain syndrome type 1 in the medico-legal setting: High rates of somatoform disorders, opiate use and diagnostic uncertainty

Objective The aim of this study was to review demographic and clinical characteristics of patients with complex regional pain syndrome type 1 (CRPS) seen in a UK medico-legal setting - particularly the relationship between CRPS and somatoform disorders. Methods Fifty consecutive cases of CRPS (interviewed 2005-2016) undergoing psychiatric assessment were reviewed. A systematic assessment of mental states was conducted via interview and examination of medical/psychiatric records. Thirty patients also completed the Brief Illness Perception Questionnaire (BIPQ). Results Sixty per cent of patients ( n = 30) were female, and the mean age was 43 years. Twenty-two per cent ( n = 11) were employed, and 60% ( n = 30) received disability benefits. Symptoms were reported in the upper limb (62%; n = 31), lower limb (30%; n = 15), both (6%; n = 3) or elsewhere (2%; n = 1). Eighty-four per cent ( n = 42) satisfied DSM-5 criteria for current somatoform disorder. A history of more than two pain-related functional somatic syndromes (e.g. non-cardiac chest pain) was found in 42% ( n = 21) and functional neurological symptoms (e.g. 'claw-hand') in 42% ( n = 21). BIPQ scores resembled those associated with somatoform disorders and disorders mediated by psychological factors (e.g. irritable bowel syndrome). In 38% ( n = 19), the CRPS diagnosis was disputed among experts. A history of depression was noted in 60% ( n = 30), panic attacks in 20% ( n = 10) and alcohol/substance misuse in 18% ( n = 9). Opiates were prescribed to 64% ( n = 32). Conclusions Patients diagnosed with CRPS involved in litigation have high rates of prior psychopathology (mainly somatoform disorders) and pain-related disability for which opiate use is common. They risk an adverse reaction to limb pain 'shaped' by maladaptive illness beliefs. The CRPS diagnosis lacks reliability in medico-legal settings and may cause iatrogenic harm.

Motor Retraining (MoRe) for Functional Movement Disorders: Outcomes From a 1-Week Multidisciplinary Rehabilitation Program

BACKGROUND

Functional movement disorders (FMDs) are conditions of abnormal motor control thought to be caused by psychological factors. These disorders are commonly seen in neurologic practice, and prognosis is often poor. No consensus treatment guidelines have been established; however, the role of physical therapy in addition to psychotherapy has increasingly been recognized. This study reports patient outcomes from a multidisciplinary FMD treatment program using motor retraining (MoRe) strategies.

OBJECTIVE

To assess outcomes of FMD patients undergoing a multidisciplinary treatment program and determine factors predictive of treatment success.

DESIGN

Retrospective chart review.

SETTING

University-affiliated rehabilitation institute.

PATIENTS

Thirty-two consecutive FMD patients admitted to the MoRe program from July 2014-July 2016.

INTERVENTION

Patients participated in a 1-week, multidisciplinary inpatient treatment program with daily physical, occupational, speech therapy, and psychotherapy interventions.

MAIN OUTCOME MEASUREMENTS

Primary outcome measures were changes in the patient-rated Clinical Global Impression Scale (CGI) and the physician-rated Psychogenic Movement Disorder Rating Scale (PMDRS) based on review of standardized patient videos. Measurements were taken as part of the clinical evaluation of the program.

RESULTS

Twenty-four of the 32 patients were female with a mean age of 49.1 (±14.2) years and mean symptom duration of 7.4 (±10.8) years. Most common movement phenomenologies were abnormal gait (31.2%), hyperkinetic movements (31.2%), and dystonia (31.2%). At discharge, 86.7% of patients reported symptom improvement on the CGI, and self-reported improvement was maintained in 69.2% at the 6-month follow-up. PMDRS scores improved by 59.1% from baseline to discharge. Longer duration of symptoms, history of abuse, and comorbid psychiatric disorders were not significant predictors of treatment outcomes.

CONCLUSIONS

The majority of FMD patients experienced improvement from a 1-week multidisciplinary inpatient rehabilitation program. Treatment outcomes were not negatively correlated with longer disease duration or psychiatric comorbidities. The results from our study are encouraging, although further long-term prospective randomized studies are needed.

LEVEL OF EVIDENCE

III.

Dissociative sensibility disorders - A retrospective case series and systematic literature review

CONTEXT

Dissociative disorders present a huge challenge in clinical settings. In contrast to other dissociative symptoms, dissociative sensibility disorders are rarely focused on.

OBJECTIVE

To identify the clinical characteristics and outcomes of dissociative sensibility disorders in children and adolescents, and to review the use of diagnostic procedures.

DATA SOURCES

For the review, a literature search used Pubmed, Embase, Web of Science, and PubPsych (to 02/2015) and the reference lists of the studies identified.

STUDY SELECTION

Screening of titles and abstracts; full-text assessment by two reviewers.

DATA SELECTION

The original case series was identified by using the local data register.

DATA EXTRACTION

Two reviewers independently reviewed the data and, if they agreed on the relevance, extracted the data. In the original case series, data were extracted retrospectively from the records.

RESULTS

Sixteen studies and seven case reports were identified, including 931 cases with dissociative disorders. In 210 cases the patient suffered either from a single sensibility disorder or predominantly from sensibility disorders. We identified thirteen further cases in our cohort. In both groups there was female predominance; the mean age of manifestation was early adolescence. The timing of admissions was variable. In approximately 50% of cases a premorbid stressful life event could be identified. Over 75% of cases had a good prognosis with complete resolution.

LIMITATIONS

Retrospective character of our own data collection, partially missing differentiation between the subgroups of dissociative disorders in the reviewed studies.

CONCLUSIONS

There is no uniform procedure for diagnostic work-up. The overall short-term prognosis is good.

[Differential diagnosis of dissociative seizures]

Patient history taking and semiology provide seminal clues to the diagnosis of dissociative seizures. Openness and alertness of the treating physician are essential. Video-electroencephalogram(EEG)-based analyses of the events are crucial to establish the correct diagnosis, particularly in complex cases. The patient-doctor relationship is of particular importance in order to successfully motivate the patient for psychotherapeutic treatment. Coexisting psychiatric morbidity as well as other functional somatic symptoms must be actively explored. Current changes in the established diagnostic manuals, including ICD-11, reflect the ongoing vivid interest and controversial discussions in the field of dissociative disorders.

Impact of Transcranial Magnetic Stimulation on Functional Movement Disorders: Cortical Modulation or a Behavioral Effect?

Introduction

Recent studies suggest that repeated transcranial magnetic stimulation (TMS) improves functional movement disorders (FMDs), but the underlying mechanisms are unclear. The objective was to determine whether the beneficial action of TMS in patients with FMDs is due to cortical neuromodulation or rather to a cognitive-behavioral effect.

Method

Consecutive patients with FMDs underwent repeated low-frequency (0.25 Hz) magnetic stimulation over the cortex contralateral to the symptoms or over the spinal roots [root magnetic stimulation (RMS)] homolateral to the symptoms. The patients were randomized into two groups: group 1 received RMS on day 1 and TMS on day 2, while group 2 received the same treatments in reverse order. We blindly assessed the severity of movement disorders before and after each stimulation session.

Results

We studied 33 patients with FMDs (dystonia, tremor, myoclonus, Parkinsonism, or stereotypies). The median symptom duration was 2.9 years. The magnetic stimulation sessions led to a significant improvement (>50%) in 22 patients (66%). We found no difference between TMS and RMS.

Conclusion

We suggest that the therapeutic benefit of TMS in patients with FMDs is due more to a cognitive-behavioral effect than to cortical neuromodulation.