Track topics on Twitter Track topics that are important to you
This study will use magnetic resonance imaging (MRI) scans to explore how the brain changes (reorganizes itself) in response to learning and to brain lesions in healthy people and people with various physical disabilities.
Normal volunteers and patients with disabilities including blindness, limb amputation, hemispherectomy (removal of a cerebral hemisphere), and stroke may be eligible for this study. Candidates will be screened with medical and neurological examinations.
Participants will have MRI scans while they lie still or perform certain movements, as instructed. MRI uses a strong magnetic field and radio waves instead of X-rays to show structural and chemical changes in tissues. During the scan, the subject lies on a table in a narrow cylinder containing a magnetic field. He or she can speak with a staff member through an intercom system at all times during the procedure. All participants will first have a scan to show brain structure, which will take about 30 minutes. A second scan will measure blood flow or biochemical concentration and will take from 1 to 2 1/2 hours.
Depending on their disability, patients will participate in one of the following tests:
- Blindness-This will study the ability of blind people to process tactile information.
- Stroke- This will study mechanisms underlying recovery of motor function after stroke. The patient will perform voluntary movements or remain still during the scan.
- Amputation- This will study mechanisms underlying the ability of the brain to reorganize after amputation. The patient will move different parts of the body or remain still during the scan.
- Hemispherectomy- This will study mechanisms underlying the ability of one side of the brain to control movements of both arms. The patient will make different kinds of movements during the scan.
Normal volunteers will participate in one of the following tests:
- Use-dependent plasticity- This will evaluate the effectiveness of amphetamine and placebo in demonstrating brain flexibility. The volunteer will take an amphetamine or placebo (inactive pill) before the scan and then perform a specific exercise using the thumb.
- Motor fatigue- This will study the mechanisms that underlie fatigue, which affect many patients with neurological conditions. The volunteer will contract muscles in the forearm and hand for several minutes until he or she feels fatigue.
- Light deprivation- This will evaluate changes in the brain that occur after light deprivation. The volunteer will remain at rest in the scanner for up to 150 minutes.
- Somatosensory stimulation-This will examine whether stimulation of the wrist can cause changes in hand representation in the part of the brain that controls movement. The volunteer will make hand movements at different times during the test. In addition, mild electric shocks will be delivered to the wrist for up to 2 hours. Although the shock intensity is regulated to avoid pain, there may be some discomfort.
The purpose of this protocol is to investigate plastic changes in human cerebral cortex in health and disease. The overall hypothesis is that it is possible to identify neuroimaging patterns reflecting reorganization in the human cerebral cortex using fMRI and that it is possible to obtain information on the mechanisms underlying some of these plastic changes by using magnetic resonance spectroscopy (MRS) of GABA. This information is potentially important for the understanding of mechanisms of cortical reorganization operating in humans. Patients and normal volunteers will be scanned at rest and during performance of different tasks. These studies should provide new information on mechanisms of human plasticity. The MRI techniques used for that purpose are functional MRI (fMRI), MR spectroscopy (MRS), and conventional MRI with magnets between 1.5 and 4 tesla.
National Institute of Neurological Disorders and Stroke (NINDS)
National Institutes of Health Clinical Center (CC)
Published on BioPortfolio: 2014-08-27T03:57:19-0400
Absorption, distribution, metabolism, and excretion (ADME) study with 14C in healthy young men.
The purpose of this study is to understand how consuming healthy cookies every day for two weeks will affect different types of fat in the blood. Specifically, the overall goal of this stu...
To assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of IMA-026 administered subcutaneously (SC) or intravenously (IV) in healthy adults.
Using an operational continuum of healthy aging developed by U.S. researchers, we sought to estimate the prevalence of healthy aging among older Spaniards, inform the development of a definition of he...
Unhealthy eating behaviors contribute to obesity and chronic illness. This study examined the relative contributions of a healthy-eater self-schema (a self-conception as a healthy eater) and nutrition...
China has the largest population in the world, and its health levels have greatly affected the healthy development of the population of the world. Healthy China 2030 is a breakthrough for ensuring tha...
This study assesses how the nation's preeminent health promotion and disease prevention initiative, Healthy People, is utilized by key stakeholders.
Healthy People Programs are a set of health objectives to be used by governments, communities, professional organizations, and others to help develop programs to improve health. It builds on initiatives pursued over the past two decades beginning with the 1979 Surgeon General's Report, Healthy People, Healthy People 2000: National Health Promotion and Disease Prevention Objectives, and Healthy People 2010. These established national health objectives and served as the basis for the development of state and community plans. These are administered by the Office of Disease Prevention and Health Promotion (ODPHP). Similar programs are conducted by other national governments.
Governmental guidelines and objectives pertaining to public food supply and nutrition including recommendations for healthy diet and changes in food habits to ensure healthy diet.
Surgical reinnervation of a denervated peripheral target using a healthy donor nerve and/or its proximal stump. The direct connection is usually made to a healthy postlesional distal portion of a non-functioning nerve or implanted directly into denervated muscle or insensitive skin. Nerve sprouts will grow from the transferred nerve into the denervated elements and establish contact between them and the neurons that formerly controlled another area.
Process of evaluating the health of a patient and determining if they are healthy enough for surgery.
Dietary patterns which have been found to be important in reducing disease risk.
Radiology is the branch of medicine that studies imaging of the body; X-ray (basic, angiography, barium swallows), ultrasound, MRI, CT and PET. These imaging techniques can be used to diagnose, but also to treat a range of conditions, by allowing visuali...
Of all the types of Dementia, Alzheimer's disease is the most common, affecting around 465,000 people in the UK. Neurons in the brain die, becuase 'plaques' and 'tangles' (mis-folded proteins) form in the brain. People with Al...
Within medicine, nutrition (the study of food and the effect of its components on the body) has many different roles. Appropriate nutrition can help prevent certain diseases, or treat others. In critically ill patients, artificial feeding by tubes need t...