View clinical trials related to Brain Diseases.
Filter by:This study will examine differences in how the brain processes English and Korean in native Korean speakers who are fluent and non-fluent in English as a second language. It is thought that people who are non-fluent in a second language process the second language differently from their native language-using different areas of the brain and requiring additional working memory. The study will increase understanding of language acquisition, brain plasticity and bilingualism. Native Korean speakers between 18 and 50 years of age with English as a second language may be eligible for this study. Three groups of individuals will be enrolled: 1) less fluent bilinguals - those who have lived in the United States for at least 1, but less than 2 years and studied English after age 12 and who have a TOEFL (Test of English as a Foreign Language) score above 550; 2) fluent bilinguals with early acquisition - those who were exposed to English before age 7 and lived in the United States after that; and 3) fluent bilinguals with late acquisition - those who were exposed to English after age 12 and lived in the United States after age 10. People with a history of head injury or neurological or thought disorder, left-handed people, and people who cannot read the material used in the study will be excluded from the study. Participants will undergo magnetic resonance imaging (MRI) scanning while reading words in English or Korean; while translating from one language to the other; and while answering questions about the meaning of words in each language. MRI uses a strong magnetic field to image brain tissue. The patient lies on a table that slides into a narrow metal cylinder, which is the scanner. The head is restrained gently with foam padding to limit movement. The patient can see out of the scanner through a mirror and is in contact with the technician via an intercom at all times during the procedure. The scans measures blood flow to different parts of the brain, providing information about what brain regions are being used during the tasks performed. Another scan will be done to obtain a detailed picture of the brain's structure. This study will evaluate the usefulness of MRI in identifying brain areas involved in processing different languages and increase knowledge about how illness affects brain function. It may help plan treatment for bilingual patients who must undergo brain surgery for uncontrolled epilepsy or who have a neurological disorder affecting different languages with varying degrees.
The purpose of this study is to learn more about stroke and obtain information that may serve as the basis for future investigations. It will 1) establish a registry of patients with cerebrovascular disease (stroke); 2) characterize the natural history of acute stroke and transient ischemic attacks (TIA)-an interruption of blood flow to the brain that causes stroke symptoms for a short period of time); and 3) evaluate the data to generate ideas for future studies. Patients 18 years of age or older with suspected acute stroke or TIA may be eligible for this study. Subjects will be recruited from patients who present with stroke at the emergency department of Suburban Hospital in Bethesda, Maryland. The study will gather data collected from diagnostic and laboratory tests the patient undergoes as part of standard medical care, including findings of medical and neurological examinations and other tests. In addition, studies will be done for research purposes only to gather data about stroke and TIA. These may include the following: - Blood and urine tests not more than 2 tablespoons of blood will be drawn for various tests. - Electrocardiogram (EKG) (heart tracing)-electrodes placed on the chest wall detect the heartbeat and heart rhythm. - Computed tomography (CT) scan of the head-specialized X-rays are used to obtain images of the brain. - Magnetic resonance imaging (MRI) of the brain-a strong magnetic field and radio waves are used to produce images that provide information about the brain tissue and blood vessels. - Transcranial Doppler (TCD)-sound waves are used to image the arteries of the brain and neck. - Echocardiogram-sound waves are used to image the heart and evaluate heart function. Patients may be asked to return to Suburban Hospital for follow-up testing in 1, 3, and/or 12 months, when some of these tests may be repeated to assess changes over time
OBJECTIVES: I. Assess the effect of lactulose on the circadian rhythm of plasma melatonin in patients with subclinical hepatic encephalopathy. II. Assess the intrasubject variability of circadian melatonin levels and neuropsychological tests. III. Assess which elements of the neuropsychological test battery show the response to lactulose.
Effective treatment and prevention strategies for childhood stroke and porencephaly can only be developed once the causes are understood. There is increasing evidence that inherited and acquired coagulation abnormalities alone or in combination with environmental factors, predispose to arterial and venous thrombosis. Inherited abnormalities of factor V Leiden, prothrombin, protein C, protein S, and antithrombin III may account for many of these thromboses. At present there is little information on the existing distribution of these coagulation anomalies in children with thrombosis. Recent reports also suggest that these clotting abnormalities may be responsible for some instances of intracranial hemorrhage, porencephaly, cerebral palsy and fetal death. This study will measure the frequency of several coagulation factor abnormalities (factor V Leiden, prothrombin 20210A, protein C, protein S, antithrombin III, and antiphospholipid antibodies) in children with a history of porencephaly and stroke, and will compare these to the prevalence of these mutations in population controls and family members. We will also describe the exogenous conditions which in concert with these coagulation factors, may have led to the development of thrombosis in these children....
The purpose of this study is to use brain imaging technology to compare differences in brain structure, chemistry, and functioning in individuals with brain and mental disorders compared to healthy volunteers. Schizophrenia is a brain disorder that results from subtle changes and abnormalities in neurons. These deficits likely occur in localized regions of the brain and may result in widespread, devastating consequences. The neuronal abnormalities are inherited through a complex combination of genetic and environmental factors. Brain imaging technologies can be used to better characterize brain changes in individuals with schizophrenia. This study will use magnetic resonance imaging (MRI) scans to identify predictable, quantifiable abnormalities in neurophysiology, neurochemistry and neuroanatomy that characterize schizophrenia and other neurological and neuropsychiatric disorders....
The purpose of this study is to collect and study the brain tissue of deceased individuals to learn more about the nervous system and mental disorders. Information gained from donated tissue may lead to better treatments and potential cures for nervous system and mental disorders. This study will ask relatives of deceased individuals to donate the brains of their deceased relatives to allow further study of neurological and psychiatric disorders. We do not accept prospective donations.
AMENDED 07/07/93: To evaluate whether continuous infusion AZT will impact neurodevelopmental deficits associated with HIV infection or alter rate of encephalopathy progression in children who have failed to improve or shown progression of these deficits despite optimal AZT therapy. AMENDED: To assess whether didanosine (ddI) will be better tolerated than AZT administered by either continuous intravenous delivery or oral administration (ddI arm removed per amended version).To determine whether ddI will achieve comparable clinical efficacy as the continuous intravenous route of delivery of AZT, and to assess whether either or both of these regimens are superior to that achieved with an intermittent AZT dosage schedule. To determine whether there are differences in patient or parent (guardian) compliance between the three treatment regimens. Original design: To determine whether the pharmacokinetic profile (bloodstream levels) of zidovudine (AZT) influences its effectiveness on HIV infection in children. That is, the study seeks to find out whether there is a difference in the effect of AZT when given as a continuous intravenous infusion (and, if available, an oral sustained release dose) compared to an intermittent (not continuous) dose given orally every 6 hours. The study also plans to determine (1) whether there are differences in the tolerance and side effects associated with AZT when given on an intermittent schedule as opposed to a steady-state schedule; (2) the extent of variation from patient to patient in AZT levels and whether the plasma and cerebrospinal fluid levels of AZT are related to the degree of therapeutic effectiveness; and (3) whether there are differences in the response of children who acquired HIV infection perinatally (just before, during, or just after the time of birth) versus those who acquired HIV infection by transfusion. One of the most serious effects of HIV disease in children is neuropsychological deterioration (relating to mental and nervous system functioning). This complication affects the vast majority of HIV infected children. A previous study of continuous intravenous administration of AZT in pediatric patients with HIV infection showed consistent and dramatic improvements of symptoms in all patients that had shown neurodevelopmental deficits or abnormalities. These improvements were seen within 3 to 4 weeks after AZT treatment was started. Neurodevelopmental improvements have been sustained on AZT, usually showing steady improvement which, in some patients, was associated with restoration of pre-HIV intellectual and neurological function. This study also showed an increase in the IQ scores of children receiving continuous infusion of AZT who did not have overt clinical evidence of encephalopathy (disease of the brain). Thus changes in cognitive function may be among the earliest signs of AIDS encephalopathy and underscores the need to start therapies that will treat the central nervous system in patients who appear to be clinically intact. A study comparing continuous infusion to intermittent dosing of AZT showed a significant increase in IQ scores for those children receiving the continuous dose compared to those treated with the intermittent schedule. Although a portable infusion pump allows patients to receive continuous infusion of AZT, a sustained release oral formulation that could provide a continuous release of AZT into the bloodstream would be highly desirable.
To determine the safety and CSF penetration of combined ganciclovir and foscarnet treatment for presumed cytomegalovirus encephalitis or radiculomyelopathy. This study proposes to investigate the use of combined ganciclovir and foscarnet to maximize the antiviral regimen. Current evidence suggests that a combination of ganciclovir and foscarnet may be the most efficacious therapy and appears to be well tolerated. This study will provide key information regarding safety and CSF penetration of the drugs available for treatment of these lethal diseases. It will also provide preliminary information regarding virologic factors relevant to CMV CNS disease. The study will also provide further data about the natural history of CMV brain infection detected by a combination of symptom complex and PCR identification of CMV in CSF and the potential of semi-quantitative PCR evaluation of the CSF for the disease.