Active clinical trials for "Essential Tremor"

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.

This is a study of subjects with the St. Jude Medical Infinity deep brain stimulation (DBS) system who undergo an MRI imaging procedure. Enrollment may occur before DBS implant, or when an MRI scan is planned in a subject with an existing implant. There will be a follow-up visit one month after the MRI procedure to document any adverse events and verify device functionality.

Background: Essential tremor is when a person has tremor, but no other neurological symptoms. Dystonic tremor is when a person also has dystonia. Dystonia is a condition in which muscle contraction causes changes in posture. Researchers do not fully know what areas of the brain cause these tremors, or how the types differ. They also do not know what tests can identify the differences. Objective: To look at differences between essential tremor and dystonic tremor. Eligibility: People ages 18 and older with or without tremor Design: Participants will be screened with medical history, physical exam, and urine tests. Those with tremor will complete questionnaires about how tremor affects them. The screening and study visits can be done on the same day or on separate days. Participants will have 1 or 2 study visits. These include magnetic resonance imaging (MRI) and tremor testing. For MRI, participants will lie on a table that slides in and out of a cylinder that takes pictures. Sensors on the skin measure breathing, heart rate, and muscle activity. This takes about 2 hours. Tremor testing will include transcranial magnetic stimulation (TMS), electrical stimulation of the fingers, doing a movement task, and recording of tremor movements. For TMS, two wire coils will be held on the scalp and a brief magnetic field will be produced. A brief electrical current will pass through the coils. For the other tests, small sticky pad electrodes will be put on the skin. Participants will move their hand when they hear a sound. They will get weak electrical shocks to their fingers. These tests will take 3-4 hours. Participants can take part in either or both parts of the study.

Background: Researchers have some data on how the brain controls movement and why some people have tremor. But the causes of tremor are not fully known. Researchers want to study people with tremor to learn about changes in the brain and possible causes of tremor. Objective: To better understand how the brain controls movement, learn more about tremor, and train movement disorder specialists. Eligibility: People ages 18 and older with a diagnosed tremor syndrome Healthy volunteers ages 18 and older Design: Participants will be screened with: Medical history Physical exam Urine tests Clinical rating scales Health questions They may have electromyography (EMG) or accelerometry. Sensors or electrodes taped to the skin measure movement. Participation lasts up to 1 year. Some participants will have a visit to examine their tremor more. They may have rating scales, EMG, and drawing and writing tests. Participants will be in 1 or more substudies. These will require up to 7 visits. Visits could include the following: EMG with accelerometry Small electrodes taped on the body give small electric shocks that stimulate nerves. MRI: Participants lie on a table that slides into a cylinder that takes pictures of the body while they do simple tasks. Small electrodes on the scalp record brain waves. A cone with detectors on the head measures brain activity while participants do tasks. A wire coil held on the scalp gives an electrical current that affects brain activity. Tests for thinking, memory, smell, hearing, or vision Electrodes on the head give a weak electrical current that affects brain activity. Photographs or videos of movement Participant data may be shared with other researchers.

The proposed study will capitalize on the early predictive information stored in an individual's genetic risk for Parkinson Disease (PD) in combination with the subtle features of tremors that can be extracted from movement data gathered by modern compact accelerometers in order to determine if accurate discrimination of essential tremor (ET) from PD can be achieved. Both of these technologies have a proven but somewhat limited ability to inform diagnosis of PD or differentiation of PD from ET - especially at early stages of the disease. The investigators hypothesize that a combination of prior genetic risk and current disease symptomology can synergize for accurate and early discrimination of PD from ET and ultimately inform a cost effective approach to movement disorder diagnosis. In this study, the investigators will collect blood from individuals with confirmed late-onset diagnosis of PD and ET. Gold standard diagnosis status will be determined via the Unified Parkinson's Disease Rating Scale (UPDRS) - the accepted clinical gold standard for Parkinson's Disease diagnosis. DNA will be extracted from blood samples to characterize the genetic risk of individuals for PD via proven genetic risk models. In addition, participants will wear a wristwatch-like accelerometer device that will track their movements (tremors) at high temporal resolution and transmit movement data via a smartphone. Cognitive distraction tasks will be administered via mobile phones while simultaneously collecting movement data. Predictive tremor features will be extracted from movement data via signal processing approaches - e.g. discrete wavelet transformation. A final predictive model combining movement tracking information and genetic information will be designed in attempt to distinguish PD from ET individuals.

The present study aims at investigating cognitive functions requiring orbitofrontal control, namely decision-making and facial emotion recognition. The investigators hypothesize that decision-making and facial emotion recognition are impaired in patients with essential tremor (ET) due to frontal lobe dysfunction which may have consequences in daily social life.

The objective of this study is to evaluate the safety and feasibility of Auto Focusing (AF) echo imaging using the ExAblate Neuro system

Research from our group has demonstrated modulation of PEFR in patients with STN and PAG stimulation. However, the effect of VIM (motor thalamus) stimulation remains to be investigated. Our group has also been involved in research that indicates that VIM stimulation may reduce perception of breathlessness. However, methodological factors limit the conclusions that can be drawn from this prior work. N-of-1 trials, organised as a randomised multiphase crossover design, are uniquely well suited for DBS research where stimulation can be switched ON and OFF, and with simple tests that can be done quickly, multiple times. PEFR and breath-holding are simple tests that we will test in this way. Other respiratory tests will be carried out along side, as optional, in a single phase design. We aim to offer this study to a continuous cohort of patients scheduled to undergo VIM (ET/DT) DBS at our institution. We will establish a pre-operative baseline of respiratory function, and then perform the n-of-1 trial post-operatively, soon after the patient returns to hospital to receive their DBS programming.