Background: \- Functional and structural magnetic resonance imaging (MRI) techniques have allowed researchers to map and study how the brain works when at rest and when engaged in specific tasks. MRI scans have provided more information about how drugs affect the brain, and about how drug addiction changes the brain and influences behavior, mood, and thinking processes. To better understand the underlying mechanism of drug addiction and to develop strategies for more effective treatment, researchers are interested in developing new MRI techniques to study the effects of addiction on the brain. Objectives: \- To develop new functional and structural MRI techniques, and to evaluate their potential use in brain imaging studies related to addiction. Eligibility: * Individuals between 18 and 80 years of age. * Participants may be smokers or nonsmokers, and may use drugs or not use drugs. Design: * During the initial screening, participants will complete questionnaires about family and personal history, drug use, and other information as required by the researchers. Participants who will be asked to complete tasks during the MRI scan will be shown how to perform these tasks before the scanning session. * Before each study session, participants may be asked to complete some or all of the following: questions about their drug use during the last week, a breathalyzer test, a urine drug-use assessment, a urine pregnancy test, or a measure of carbon monoxide. Participants will also provide blood samples before the start of the scan. * For each scanning session, participants will have an MRI scan that will last approximately 2 hours. * MRI scans may include specific tasks to be performed during the scan, or an experiment that studies the brain's response to carbon dioxide....
See this in plain English?
AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
To develop a simultaneous perfusion and BOLD imaging technique with improved functional contrasts and reduced susceptibility artifacts for determination of CMRO2 during brain activation
Timeframe: at each visit
To develop efficient methods to reduce image artifacts caused by susceptibility-induced field inhomogeneity and head motion, and therefore to improve reliability and sensitivity of functional imaging
Timeframe: at each visit
To develop an imaging technique to identify fiber crossing in the brain based on high-angular resolution measurements of apparent diffusion coefficient (ADC), and subsequently to develop improved fiber tracking techniques to delineate neuronal p...
Timeframe: at each visit
To develop MRS techniques that are able to reliably measure metabolite and neurotransmitter concentrations in the brain at 3 Tesla, and to evaluate their feasibility and efficacy in drug addiction studies
Timeframe: at each visit
To integrate genetic analysis with morphological and functional measurement of the amygdala, hippocampus, and other regions, which may help to account for some of the noise in these measurements
Timeframe: at each visit
To assess effects of neuromodulation techniques, such as TMS and TRPMS, on brain activity and relevant MRI signals
Timeframe: at each visit