Tremor

Background: A movement disorder is a condition that causes a person s body to move in ways that are not normal. There are different types. Some disorders cause movements people can t control, such as tics or shaking. Some cause reduced or slow movements. Movement disorders can cause disability in people. Sometimes members of the same family will have the same disorder. Researchers want to learn more about how people develop these disorders. This research could lead to better treatments. Objective: This natural history study will collect data on people with different types of movement disorders. It will also collect data on their family members. The data will support further research. Eligibility: Children and adults aged 2 years and older who have a movement disorder. Family members of people with movement disorders are also needed. Design: Participants will undergo screening. They will have a physical exam. Researchers will look at their existing medical images. Any photographs or videos of their movements will also be reviewed. Most participants will come to the NIH clinic for only 1 visit. They will answer questions about their condition. They will have normal tests used to diagnose their condition. They may have blood tests and different types of imaging scans. They may have tests to see how well their nerves function. The tests used will depend on the type of disorder they have. Family members will have some of the same tests as people with disorders. Participants will not receive any new treatments. Some participants may be asked to return for a follow-up visit. Up to 4000 people may participate.

Parkinson's disease (PD) is a prevalent neurodegenerative disorder characterized by different motor symptoms, including tremor, which is particularly difficult to manage. Common treatments, such as dopaminergic therapy, can have limitations in efficacy. Recent advancements in non-invasive brain stimulation, specifically phase-adaptive transcranial alternating current stimulation (tACS), offer a promising approach to reduce PD tremor. In the current project, a newly developed closed-loop system delivers precisely synchronized cerebellar tACS by aligning stimulation with the intrinsic hand tremor signal. The study will assess the efficacy of this novel approach to reduce hand tremor in PD patients.

The evaluation of neurosurgical outcomes varies from center to center, and the predictive factors that determine these outcomes are not fully known or shared. This study aims to assess outcomes and their predictors using measures agreed upon by the participating centers. Standardizing the evaluation of outcomes and predictors improves the quality of research, allows for data comparison, and facilitates a "common language" in routine clinical practice. Most importantly, it influences therapeutic decisions in various neurosurgical conditions. Clinically, the identified predictors can also be used during preoperative assessments to provide more precise guidance to patients undergoing surgery.

The purpose of this international study is to evaluate long-term safety and effectiveness of Abbott deep brain stimulation (DBS) systems for all indications, including Parkinson's disease, essential tremor or other disabling tremor and dystonia.

This study investigates magnetic resonance-guided focused ultrasound thalamotomy (MRgFUSth) for people with Parkinson's disease (PD) and tremor not responding to conventional standard doses of dopamine replacement therapy. The aim is to identify clinical and imaging biomarkers predictive of sustained tremor control up to 24 months after MRgFUSth treatment. Participants will undergo a suprathreshold levodopa test and ¹⁸F-DOPA PET imaging to evaluate dopaminergic and serotonergic involvement in tremor. All participants will receive MRgFUSth and be followed for 24 months with standardized clinical, cognitive, and quality-of-life assessments. The study seeks to improve understanding the possible mechanisms of tremor relapse and inform patient selection for MRgFUSth in PD.

The researchers will examine functional neural correlates that differentiate between laryngeal dystonia and voice tremor and contribute to disorder-specific pathophysiology using a cross-disciplinary approach of multimodal brain imaging.

The researchers will systematically evaluate current and novel clinical voice assessment tools and measures to elucidate distinct clinical phenotypes of those with laryngeal dystonia and voice tremor.

The goals of this project are 1) to determine the incidence of neurological voice disorders in patients with dystonia and essential tremor undergoing deep brain stimulation (DBS), 2) investigate the neuroimaging and intracranial neurophysiology correlates of voice dysfunction in these subjects, and subsequently 3) determine the effects of DBS on voice function.

The goal of this observational study is to learn about functional neurological disorders in patients with common non-functional movement disorders ("functional overlay"). The main questions it aims to answer are: * What is the frequency of functional neurological disorders in patients with non-functional movement disorders (functional overlay)? * What are the characteristics of functional neurological disorders in patients with non-functional movement disorders? Participants will be examined clinically and electrophysiologically, the examinations consist of: * a neurological examination * neuropsychological testing * electrophysiological tremor diagnostic * questionnaires about psychological, biological and social risk factors Researchers will compare patients with functional motor disorders to patients wit non-functional movement disorders to see if they differ from each other regarding the functional symptoms.

The purpose of this study is to determine the changes in quality of life and degree of tremor for patients with essential tremor or Parkinsonian tremor who are treated by stereotactic radiosurgery (SRS). This is a questionnaire-based study. Please see Detailed Description below for more information.

This objective of this study is to document the safety and feasibility of electrical stimulation of the deep cerebellar nuclei for refractory tremor using the Medtronic Percept RC Deep Brain Stimulation System. The population will consist of patients that have either failed a prior intervention (Vim DBS or HIFU thalamotomy) or determined to not be suitable candidates for Vim DBS or HIFU thalamotomy because they have a cerebellar outflow or MS-related tremor. Those patients with a previous intervention, must have a prior diagnosis of ET, cerebellar outflow tremor, or MS-related tremor. Subjects without a previous intervention must have a diagnosis of cerebellar outflow tremor or MS-related tremor.

In clinical practice, it is sometimes difficult to establish whether a patient's tremor is due to Parkinson's disease or essential tremor. The distinction is crucial as the health implications differ significantly between the two conditions. Therefore, the present study aims to develop a diagnostic method based on machine learning techniques to help differentiate whether a patient's tremor is due to one condition or the other. To achieve this, 110 patients with tremor, correctly diagnosed with either Parkinson's disease or essential tremor, will participate. They will undergo two diagnostic tests (tapping test and Archimedean spiral) to capture data that can be processed using machine learning techniques.

Essential tremor is a common neurological disease, the most severe form of which combines postural and intention tremor, with significant physical, psychological and social repercussions. It is in these most severe forms that surgical lesioning of the ventro-intermediate nucleus of the thalamus (VIM) has been proposed. The VIM and its region of interest are almost impossible to identify directly on imaging (especially MRI), as it is part of the thalamus, which has the same intensity. To identify it, teams use average coordinates from stereotactic atlases (imprecise due to the high inter-individual variability of brain anatomy) or retrospective series of implanted patients. The hypothesis of the present trial is that the VIM-RS-LAT-1.0 algorithm developed by RebrAIn for radiosurgery will enable targeting that is at least as effective as conventional targeting. This is a single-center, controlled study, the primary endpoint of which will be assessed at one year, in a blinded, phase 3, comparative, non-inferiority, randomized study in two parallel groups of patients with severe tremor undergoing radiosurgery. In the control group, VIM will be targeted conventionally, and in the experimental group, VIM will be targeted by the RebrAIn algorithm (VIM-RS-LAT-1.0 model) of radiosurgery.

This is a randomized open label study in de novo liver transplant recipients that aims to compare the risk of tacrolimus induced tremors with once daily extended-release formulation, Envarsus, versus the twice daily immediate-release formulation. Both formulations of tacrolimus are currently approved for the prevention of rejection in liver transplant patients.