Machine learning classification of functional neurological disorder using structural brain MRI features.

BACKGROUND: Brain imaging studies investigating grey matter in functional neurological disorder (FND) have used univariate approaches to report group-level differences compared with healthy controls (HCs). However, these findings have limited translatability because they do not differentiate patients from controls at the individual-level. METHODS: 183 participants were prospectively recruited across three groups: 61 patients with mixed FND (FND-mixed), 61 age-matched and sex-matched HCs and 61 age, sex, depression and anxiety-matched psychiatric controls (PCs). Radial basis function support vector machine classifiers with cross-validation were used to distinguish individuals with FND from HCs and PCs using 134 FreeSurfer-derived grey matter MRI features. RESULTS: Patients with FND-mixed were differentiated from HCs with an accuracy of 0.66 (p=0.005; area under the receiving operating characteristic (AUROC)=0.74); this sample was also distinguished from PCs with an accuracy of 0.60 (p=0.038; AUROC=0.56). When focusing on the functional motor disorder subtype (FND-motor, n=46), a classifier robustly differentiated these patients from HCs (accuracy=0.72; p=0.002; AUROC=0.80). FND-motor could not be distinguished from PCs, and the functional seizures subtype (n=23) could not be classified against either control group. Important regions contributing to statistically significant multivariate classifications included the cingulate gyrus, hippocampal subfields and amygdalar nuclei. Correctly versus incorrectly classified participants did not differ across a range of tested psychometric variables. CONCLUSIONS: These findings underscore the interconnection of brain structure and function in the pathophysiology of FND and demonstrate the feasibility of using structural MRI to classify the disorder. Out-of-sample replication and larger-scale classifier efforts incorporating psychiatric and neurological controls are needed.

Sensory Processing Difficulties and Occupational Therapy Outcomes for Functional Neurological Disorder: A Retrospective Cohort Study.

Background and Objectives: Occupational therapy (OT) consensus recommendations and articles outlining a sensory-based OT intervention for functional neurological disorder (FND) have been published. However, limited research has been conducted to examine the efficacy of OT interventions for FND. We performed a retrospective cohort study aimed at independently replicating preliminarily characterized sensory processing difficulties in patients with FND and reporting on clinical outcomes of a sensory-based OT treatment in this population. We hypothesized that (1) a history of functional seizures, anxiety, and/or post-traumatic stress disorder would be associated with increased sensory processing difficulties and (2) the number of OT treatment sessions received would positively relate to clinical improvement. Methods: Medical records were reviewed for 77 consecutive adults with FND who received outpatient, sensory-based OT care. Data from the Adolescent/Adult Sensory Profile characterized self-reported sensory processing patterns across 4 quadrants (low registration, sensory sensitivity, sensory seeking, and sensory avoidance) in this population. Following univariate screenings, multivariate linear regression analyses were performed to identify neuropsychiatric characteristics associated with discrete sensory processing patterns. Clinical improvement was quantified using an estimated, clinician-determined improvement rating ("improved" vs "not improved"), and relationships between clinical participation, baseline neuropsychiatric factors, and outcomes were investigated. Results: Patients with FND reported sensory processing patterns with elevated scores in low registration, sensory sensitivity, and sensation avoidance compared with normative values; differences in sensory processing scores were not observed across FND subtypes (i.e., motor, seizure, and speech variants). In linear regression analyses, lifetime history of an anxiety disorder, history of migraine headaches, current cognitive complaints, and a comorbid major neurologic condition independently predicted individual differences in sensory processing scores. Following a sensory-based OT intervention, 62% of individuals with FND were clinician determined as "improved." In a multivariate logistic regression analysis controlling for baseline characteristics associated with improvement ratings, number of treatment sessions positively correlated with clinical improvement. Discussion: These findings support the presence of sensory processing difficulties in patients with FND and provide Class IV evidence for the efficacy of an outpatient, sensory-based OT intervention in this population. Controlled prospective trials are warranted.

Outpatient Approach to Occupational Therapy for Paroxysmal Functional Neurologic Symptoms: Sensory Modulation Training as an Emerging Treatment.

Occupational therapy (OT) is an important treatment modality for patients with paroxysmal functional neurologic disorder (FND) symptoms. In our clinical experience, an outpatient, OT-based sensory modulation treatment can address sensory processing difficulties often endorsed by patients with paroxysmal motor FND and functional seizures. This article aims to describe in detail the goals and treatment strategies for occupational therapists to replicate this approach. This article is also an important first step in aiding the development and execution of clinical trials to further evaluate the effectiveness of sensory-based treatment in patients with FND.

Sensory Processing Difficulties in Patients with Functional Neurological Disorder: Occupational Therapy Management Strategies and Two Cases.

Functional neurological disorder (FND) is a condition at the intersection of neurology and psychiatry, with some patients experiencing sensory hypersensitivities and other sensory processing difficulties. It has been postulated that poor integration and modulation of sensory information with cognitive, affective and behavioral processes may play a role in the pathophysiology of FND. In this article, we first succinctly review the role for occupational therapy (OT) in the multidisciplinary therapeutic approach to managing patients with FND. After highlighting previously published data identifying sensory processing difficulties in patients with FND, we subsequently outline the components of the sensory-based outpatient OT program for FND at the Massachusetts General Hospital. Here, we detail how occupational therapists assess and treat sensory modulation difficulties with the aid of resources like the Adolescent/Adult Sensory Profile (AASP), The Canadian Occupational Performance Measure (COPM), and the Sensory-Motor Preference Checklist. We then report on 2 clinical cases representative of the sensory modulation difficulties endorsed by some patients with FND, illustrating how developing an individualized, sensory-based treatment plan can help improve functional neurological symptoms and overall participation in activities of daily living. Prospective, controlled research is needed to further operationalize OT-based sensory modulation interventions, as well as define the tolerability and efficacy of this intervention for pediatric and adult populations with FND.

Occupational therapy consensus recommendations for functional neurological disorder.

BACKGROUND: People with functional neurological disorder (FND) are commonly seen by occupational therapists; however, there are limited descriptions in the literature about the type of interventions that are likely to be helpful. This document aims to address this issue by providing consensus recommendations for occupational therapy assessment and intervention. METHODS: The recommendations were developed in four stages. Stage 1: an invitation was sent to occupational therapists with expertise in FND in different countries to complete two surveys exploring their opinions regarding best practice for assessment and interventions for FND. Stage 2: a face-to-face meeting of multidisciplinary clinical experts in FND discussed and debated the data from stage 1, aiming to achieve consensus on each issue. Stage 3: recommendations based on the meeting were drafted. Stage 4: successive drafts of recommendations were circulated among the multidisciplinary group until consensus was achieved. RESULTS: We recommend that occupational therapy treatment for FND is based on a biopsychosocial aetiological framework. Education, rehabilitation within functional activity and the use of taught self-management strategies are central to occupational therapy intervention for FND. Several aspects of occupational therapy for FND are distinct from therapy for other neurological conditions. Examples to illustrate the recommendations are included within this document. CONCLUSIONS: Occupational therapists have an integral role in the multidisciplinary management of people with FND. This document forms a starting point for research aiming to develop evidence-based occupational therapy interventions for people with FND.

Sensory Processing Difficulties in Functional Neurological Disorder: A Possible Predisposing Vulnerability?

BACKGROUND: Functional neurological disorder (FND) is a prevalent neuropsychiatric condition characterized by sensorimotor difficulties. Patients with FND at times report that sensory experiences trigger and/or exacerbate their symptoms. Sensory processing difficulties are also commonly reported in other psychiatric disorders frequently comorbid in FND, suggesting that contextualizing sensory profiles in FND within a biopsychosocial model may be clinically relevant. OBJECTIVE: To address this literature gap, we conducted a retrospective cohort study to examine sensory processing patterns and their relationship to other neuropsychiatric characteristics in patients with FND. METHODS: A retrospective chart review design was used to investigate sensory processing patterns, established with the Adolescent/Adult Sensory Profile self-report questionnaire, in 44 patients with FND. Univariate analyses of cross-sectional screening tests followed by multivariate linear regression analyses were performed to identify clinical factors associated with sensory processing scores in the FND cohort. RESULTS: Compared to normative data, most patients with FND reported sensory processing tendencies toward low registration, sensory sensitivity, and sensation avoiding. In multivariate regression analyses, the presence of a lifetime anxiety disorder independently predicted elevated low registration scores, while female gender and number of current medications independently predicted increased sensory sensitivity scores. In uncorrected univariate analyses only, individuals with psychogenic nonepileptic seizures were more likely to report increased sensory sensitivity and elevated low registration. CONCLUSION: These preliminary findings support sensory processing difficulties in some patients with FND. Prospective and large sample size studies are needed to investigate relationships between sensory processing profiles and neuropsychiatric comorbidities, FND subtypes, and treatment outcomes.

Functional Dystonia: Differentiation From Primary Dystonia and Multidisciplinary Treatments.

Dystonia is a common movement disorder, involving sustained muscle contractions, often resulting in twisting and repetitive movements and abnormal postures. Dystonia may be primary, as the sole feature (isolated) or in combination with other movement disorders (combined dystonia), or as one feature of another neurological process (secondary dystonia). The current hypothesis is that dystonia is a disorder of distributed brain networks, including the basal ganglia, cerebellum, thalamus and the cortex resulting in abnormal neural motor programs. In comparison, functional dystonia (FD) may resemble other forms of dystonia (OD) but has a different pathophysiology, as a subtype of functional movement disorders (FMD). FD is the second most common FMD and amongst the most diagnostically challenging FMD subtypes. Therefore, distinguishing between FD and OD is important, as the management of these disorders is distinct. There are also different pathophysiological underpinnings in FD, with for example evidence of involvement of the right temporoparietal junction in functional movement disorders that is believed to serve as a general comparator of internal predictions/motor intentions with actual motor events resulting in disturbances in self-agency. In this article, we present a comprehensive review across the spectrum of FD, including oromandibular and vocal forms and discuss the history, clinical clues, evidence for adjunctive "laboratory-based" testing, pathophysiological research and prognosis data. We also provide the approach used at the Massachusetts General Hospital Dystonia Center toward the diagnosis, management and treatment of FD. A multidisciplinary approach, including neurology, psychiatry, physical, occupational therapy and speech therapy, and cognitive behavioral psychotherapy approaches are frequently required; pharmacological approaches, including possible targeted use of botulinum toxin injections and inpatient programs are considerations in some patients. Early diagnosis and treatment may help prevent unnecessary investigations and procedures, while facilitating the appropriate management of these highly complex patients, which may help to mitigate frequently poor clinical outcomes.

Diagnostic evaluation and monitoring of patients with posterior cortical atrophy.

Posterior cortical atrophy (PCA) is a progressive neurocognitive syndrome, most commonly associated with the loss of complex visuospatial functions. Diagnosis is challenging, and international consensus classification and nomenclature for PCA subtypes have only recently been reached. Presently, no established treatments exist. Efforts to develop treatments are hampered by the lack of standardized methods to monitor illness progression. Although measures developed from work with Alzheimer's disease and other dementias provide a foundation for diagnosing and monitoring progression, PCA presents unique challenges for clinicians counseling patients and families on clinical status and prognosis, and experts designing clinical trials of interventions. Here, we review issues facing PCA clinical research and care, summarize our approach to diagnosis and monitoring of disease progression, and outline ideas for developing tools for these purposes.

The Comprehensive Management of Cerebellar Ataxia in Adults.

PURPOSE OF REVIEW: In this review, we present the multidisciplinary approach to the management of the many neurological, medical, social, and emotional issues facing patients with cerebellar ataxia. RECENT FINDINGS: Our holistic approach to treatment, developed over the past 25 years in the Massachusetts General Hospital Ataxia Unit, is centered on the compassionate care of the patient and their family, empowering them through engagement, and including the families as partners in the healing process. We present the management of ataxia in adults, beginning with establishing an accurate diagnosis, followed by treatment of the multiple symptoms seen in cerebellar disorders, with a view to maximizing quality of life and effectively living with the consequences of ataxia. We discuss the importance of a multidisciplinary approach to the management of ataxia, including medical and non-medical management and the evidence base that supports these interventions. We address the pharmacological treatment of ataxia, tremor, and other associated movement disorders; ophthalmological symptoms; bowel, bladder, and sexual symptoms; orthostatic hypotension; psychiatric and cognitive symptoms; neuromodulation, including deep brain stimulation; rehabilitation including physical therapy, occupational therapy and speech and language pathology and, as necessary, involving urology, psychiatry, and pain medicine. We discuss the role of palliative care in late-stage disease. The management of adults with ataxia is complex and a team-based approach is essential.

Secure Attachment and Depression Predict 6-Month Outcome in Motor Functional Neurological Disorders: A Prospective Pilot Study.

BACKGROUND: The relationships between baseline neuropsychiatric factors and clinical outcome in patients with functional neurological disorder (FND)/conversion disorder remain poorly understood. OBJECTIVE: This prospective, naturalistic pilot study investigated links between predisposing vulnerabilities (risk factors) and clinical outcome in patients with motor FND engaged in usual care within a subspecialty FND clinic. METHODS: Thirty-four patients with motor FND were enrolled and completed baseline and 6-month follow-up psychometric questionnaires. Univariate screening tests followed by multivariate linear regression analyses were used to investigate neuropsychiatric predictors of 6-month clinical outcome in patients with motor FND. RESULTS: In univariate analyses, baseline secure attachment traits and depression as measured by the Relationship Scales Questionnaire and Beck Depression Inventory-II positively correlated with improved Patient Health Questionnaire-15 scores. In a multivariate linear regression analysis adjusting for the interval time between baseline and follow-up data collection, baseline secure attachment and depression scores independently predicted improvements in Patient Health Questionnaire-15 scores. In additional analyses, patients with a diagnosis of psychogenic nonepileptic seizures compared to individuals with other motor FND subtypes showed a trend toward worse 6-month physical health outcomes as measured by the Short Form Health Survey-36. CONCLUSION: Future large-scale, multi-site longitudinal studies are needed to comprehensively investigate neuropsychiatric predictors of clinical outcome in patients with motor FND, including functional weakness, functional movement disorders, and psychogenic nonepileptic seizures.