Clinical Research Directory

Study of New Magnetic Resonance Imaging Methods of the Brain

The purpose of this investigation is to develop improved magnetic resonance imaging (MRI) techniques and hardware for studying brain function. MRI is a diagnostic tool that provides information about brain chemistry and physiology. This study will evaluate new MRI methods for monitoring blood flow to regions of the brain in response to simple tasks. The MRI machine used in this study is more powerful than those in most hospitals, permitting a higher visual resolution. Normal healthy volunteers over 18 years old may be eligible for this study. Candidates will be screened with a medical history and questionnaire, and a neurological examination. Study participants will have a yearly MRI scan. For this procedure, the subject lies on a stretcher that is moved into a donut-shaped machine with a strong magnetic field. A lightweight circular or rectangular coil a device that improves the quality of the images may be placed on the head. The scan time varies from 20 minutes to 3 hours; most scans last between 45 and 90 minutes. During the scan, the subject may perform simple tasks, such as listening to tapes, tapping a finger, moving a hand, watching a screen, or smelling a fragrance. More complex tasks may require thinking about tones or pictures and responding to them by pressing buttons. Information from this study will be used to develop better imaging methods that will, in turn, permit a greater understanding of normal and abnormal brain behaviors. ...

Development of Magnetic Resonance Spectroscopic Imaging Techniques for Imaging Metabolites in Human Brain and Muscle

Background: \- Magnetic resonance imaging (MRI) is a widely used scanning technique to obtain images of the human body and evaluate activity in the brain. A particular MRI method called magnetic resonance spectroscopy (MRS) can be used to study brain chemistry as well, which may help researchers who are studying new treatments for psychiatric illnesses. Researchers are interested in improving current MRI and MRS techniques, as well as developing new MRI and MRS techniques to view and measure brain chemicals and brain activity. Objectives: \- To implement, develop, and optimize brain chemistry imaging techniques using magnetic resonance imaging and magnetic resonance spectroscopy. Eligibility: \- Healthy individuals between 18 and 65 years of age. Design: * This study will involve a screening visit and a scanning visit at the National Institutes of Health Clinical Center. * Participants will be screened with a full medical and physical examination, blood and urine tests, and neurological testing. * During the second visit, participants will have an MRI scan of the brain. (Participants who have received an MRI within the past year will not need to have a second one; the images of the previous scan will be used for this study.) All participants will then have an MRS scan using the same scanning equipment.

Characterization Imaging Instruments in Alcoholics and Non-Alcoholics

Background: \- People with alcoholism have differences in their brains compared with healthy people. People who are dependent on alcohol also perform differently on behavioral tasks. Researchers want to find out more about these differences. They also want to see if these differences are related to DNA. Objective: \- To see if differences in brain structure relate to personality and behavior differences in people with and without alcohol dependence. Eligibility: \- Adults age 18 and older. Design: * Participants will visit the NIH Clinical Center once during the study. * Participants will be screened with a medical history, EKG, and physical exam. They will give blood and urine samples and undergo a psychiatric interview. * Participants will be asked about their alcohol drinking, to see if they have an alcohol use disorder. * Participants will play three computerized games. Some will play these games inside a magnetic resonance imaging (MRI) scanner. * MRI: strong magnetic field and radio waves take pictures of the brain. Participants lie on a table that slides in and out of a cylinder. They will be in the scanner for about 90 minutes. They may lie still for up to 20 minutes at a time. The scanner makes loud knocking noises. They will get earplugs.