Active clinical trials for "Tremor"

Researchers are investigating improved methods of targeting deep brain stimulators for treatment of essential tremor relying on brain connectivity measures derived from MRI.

Essential Tremor (ET) is characterized by tremors affecting the arms. The investigators will examine the effects of non-pharmacological limb cooling on clinical and physiological characteristics in patients presenting with ET at three different temperatures; and will measure changes in tremor amplitude after cooling of the upper limb.

Background: - Essential tremor (ET) is a neurological disorder involving uncontrollable shaking, which over time can interfere with mobility and affect routine aspects of daily living. Several medications are used to treat ET, but these medications are often only partially effective and can have side effects. About two-thirds (66%) of people with ET have some relief from drinking alcohol, which suggests that alcohol affects the part of the brain causing the tremor. However, more research is needed to better understand the effects of alcohol or what areas of the brain might be important in the response. Objectives: To study to what extent alcohol is reducing tremor in a group of patients with essential tremor. To use transcranial magnetic stimulation to study the effects of alcohol on essential tremor. Eligibility: - Individuals who are at least 21 years of age, have been diagnosed with essential tremor and have tremor in both hands, and can tolerate being off all medications for essential tremor for up to 4 weeks. Design: This study has one screening visit (1 to 2 hours), followed by one study visit (3 to 5 hours). Participants might be asked to also take part in one additional study visit (3 to 5 hours). The maximum period between the study visits is 3 months. Participants will be screened with a medical history, physical examination, and blood tests. At this visit, participants will receive information about how to safely taper off their current ET medications before the start of the study. Participants must be willing to abstain from drinking any alcohol or caffeine (or consuming foods with caffeine such as chocolate) for at least 2 days before the study visits. Participants must also fast overnight (for at least 8 hours) before the study visits. At the first study visit, participants will receive a single drink of alcohol (mixed with a noncaffeinated drink) and will complete movement tests to determine whether the alcohol improves the tremor. Alcohol levels will be monitored throughout the visit. At the second study visit, participants will have an electrocardiogram to measure heart electrical activity and determine if they are able to safely have transcranial magnetic stimulation. Participants will then receive an intravenous infusion of alcohol and complete questionnaires during the infusion to provide information about its effects. Then, transcranial magnetic stimulation will be used to study brain electrical activity, as well as muscle movements and tremor activity, while under the influence of the alcohol infusion. After each study visit, participants will remain at the clinical center until the effects of the alcohol have worn off. Participants will be able to resume taking their ET medications after the end of the study.

The main objective of this study is to identify the superficial muscle groups involved in gene-related tremor and assess the reduction in the intensity of the tremor after transient electrical stimulation.

Deep Brain Stimulation (DBS) is an effective treatment option for individuals with debilitating tremors that do not respond to medical therapy. However, severe tremors, particularly those that develop after central nervous system insult or from multiple sclerosis, can be comprised of several underlying components that represent dysfunction within distinct brain circuits. Some of these dysfunctional brain circuits can be successfully treated with DBS while others respond poorly DBS therapy. For severe tremors, it can be very difficult to discriminate between the underlying components of a patient movement disorder and is exclusively dependent upon clinical expertise. Even with extensive clinical experience, it is difficult to reliably predict the results of DBS therapy for patients suffering from severe, debilitating tremor. In an attempt to gain more knowledge, an electromagnetic tracking system will be used which can precisely measure the position of a patient's upper extremity in space during routine neurologic examination. The goal is to use this tool to quantitatively identify various components of severe tremor, which can be discriminated based on oscillatory frequency and regularity of tremor amplitude. The purpose of this research study is to better understand the nature of complex, severe tremors by carefully measuring movement of the upper extremities with sensors during simple tasks. The goal is to break down complicated tremors into their components and then determine which components will respond to deep brain stimulation.

The purpose of this prospective, participant-blinded trial is to determine the changes in sleep architecture in a cohort of subjects who have undergone deep brain stimulation (DBS) surgery for treatment of movement disorders such as moderate to advanced Parkinson's disease (PD), tremor, or dystonia. Our preliminary observational data suggest that unilateral subthalamic nucleus (STN) DBS improves subjective sleep quality in PD patients 6 months after the procedure. The cause of this improvement in sleep quality is unknown, and this study proposes the use of polysomnography (PSG) to test whether the improvement in sleep is independent of improvement in night-time mobility associated with DBS treatment of the motor symptoms of PD, tremor, or dystonia.

The purpose of this research study is to test effectiveness of different deep brain stimulation (DBS) stimulation patterns on symptoms that may also improve the life of the battery. If these patterns are effective, the implanted batteries will be drained more slowly and last longer than currently expected. An increase in battery life may reduce the number of surgeries needed to replace them.

Pathophysiology of tremor-modulating mechanisms of propranolol and primidone in essential tremor (ET) will be studied using accelerometry with electromyography (EMG), transcranial magnetic stimulation (TMS), and eyeblink conditioning paradigm (EBCC). TMS is a well-established experimental method for studying the effects of drugs on motor cortex excitability. EBCC is a learning paradigm that can be used for studying cerebellar dysfunction since only brainstem and cerebellar functions seem to be needed for this paradigm. The investigators will use TMS to study the mechanisms of primidone and propranolol action in ET, EBCC paradigm to evaluate cerebellar dysfunction in ET patients and to show whether cerebellar dysfunction influences the effectiveness of propranolol and primidone. The investigators will clinically assess patients using The Essential Tremor Rating Assessment Scale (TETRAS) and the Scale for the Assessment and Rating of Ataxia (SARA) scales. Patients with ET will be studied prior to treatment with propranolol or primidone and re-tested 3-6 months after treatment initiation. On each visit, the investigators will clinically assess the patients and perform accelerometry, TMS measurements, and the eyeblink classical conditioning (EBCC) paradigm. The investigators hypothesize that in ET patients, baseline electrophysiological parameters will differ between responders and non-responders to propranolol and primidone and that propranolol and primidone will cause a different pattern of change in electrophysiological parameters among responders. It is hypothesized that cerebellar dysfunction will negatively correlate with patients' response to treatment.

This study's research is devoted to studying the causes of tremor, and especially essential tremor (ET), which is the most common type of tremor. Previous studies have revealed a link between harmane [HA], a dietary neurotoxin, and ET; these studies now also suggest a link between this toxin and Parkinson's disease (PD), a related tremor disorder. Yet these links are tentative rather than conclusively established; therefore, in this new patient-based proposal, which incorporates investigations spanning two continents (North America and Europe), utilizes several complementary study designs (prospective cohort, case control), and draws on several types of tissue (blood, brain), the investigator's goal is to nail down the links between HA and ET and to further solidify the emerging links between HA and PD.

The purpose of this study is to determine whether transcranial cathodal direct current stimulation (tDCS) delivered over the cerebellum can improve essential tremor.