Updates in Functional Movement Disorders: from Pathophysiology to Treatment Advances

Abstract

Purpose of Review This review discusses advances in functional movement disorders (FMD) over the past 3 years, with a focus on risk factors, diagnosis, pathophysiology, neuroimaging studies, and treatment. Recent Findings The past decade has brought a revived interest in functional movement disorders, with a growing number of studies exploring pathophysiological mechanisms. Here, we review recent studies demonstrating changes in attention, emotional and sensorimotor function in FMD. Through international collaborative efforts, progress has been made in defining biomarkers and outcome measures, an important prerequisite towards standardization of diagnosis and reporting of outcomes in clinical trials. Of particular interest are neuroimaging studies demonstrating functional and structural changes in motor and emotional brain circuits, deepening our understanding of FMD as a neurocircuit disorder and potentially paving the way towards new treatments. Currently available treatment modalities have shown successful outcomes via outpatient, inpatient, and virtual delivery. Summary The last 3 years have seen tremendous efforts to better understand, diagnose, and treat FMD. The disease model has been broadened to include a biopsychosocial formulation, and insights on the pathophysiology on FMD are informing treatment efforts. Several international multidisciplinary research collaborations are underway to define biomarkers and best outcome measures, highlighting the path towards improved standardization of future treatment trials. Additionally, the rise of telemedicine during the COVID-19 pandemic has reduced geographic barriers and paved the way for virtual therapy sessions and self-guided programs. Supplementary Information The online version contains supplementary material available at 10.1007/s11910-022-01192-9.

Bradykinesia and dystonia

“…Functional movement disorders (FMDs) are defined as abnormal movements that are involuntary and do not have a clear neurologic cause or consistent neuroanatomy [30, [92][93][94][95][96]. Functional dystonia typically presents with fixed onset, inconsistent resistance, and absence of a sensory trick [96].…”

“…Functional movement disorders (FMDs) are defined as abnormal movements that are involuntary and do not have a clear neurologic cause or consistent neuroanatomy [30, [92][93][94][95][96]. Functional dystonia typically presents with fixed onset, inconsistent resistance, and absence of a sensory trick [96]. Functional bradykinesia is characterized by an abnormal slowness of movement that is not accompanied by a decrease in movement amplitude or complete movement arrest [94].…”

Readiness potential as a neurophysiological marker of functional movement disorders

“…Наиболее интенсивно при ФДР используется метод функциональной магнитно-резонансной томографии (фМРТ), который позволяет в режиме реального времени визуализировать изменение функциональной активности головного мозга. В серии исследований с применением фМРТ было показано повышение функциональной активности постцентральной извилины, преклинья, задней поясной коры, червя мозжечка, а также нарушение интеграции нейрональных контуров, отвечающих за эмоциональный и моторный контроль [26]. Однако в настоящее время фМРТ остается сравнительно редким и дорогостоящим методом, недоступным в рутинной практике.…”

“…Следует отметить, что полученные результаты хорошо согласуются с полученными ранее данными о существенном негативном влиянии ФДР на социодемографические параметры [7,9,16]. Также с уже доступными данными согласуется выраженная длительность ФДР, подтверждающая хронический характер данного заболевания [7,26].…”