Development of Magnetic Resonance Imaging Techniques for Studying Mood and Anxiety Disorders

This study is intended to help develop new MRI imaging techniques for studying mood and anxiety disorders. Researchers believe that depression and anxiety disorders may cause structural and functional changes in the brain. This study will optimize the way MRI scans are collected to look at brain structure and examine how the brain behaves while subjects perform particular tasks. Healthy volunteers and individuals with major depressive disorder may be eligible for this study. Participants undergo magnetic resonance imaging (MRI) and neuropsychological testing. : Individuals will be asked to participate in an MRI study on one of several scanners. The scanner used will measure blood flow in the brain, concentrations of certain chemicals in the brain, or magnetic properties of the brain. The scan may involve They watching a screen presenting images or doing a task in which they respond to pictures or sounds. Participants may be asked to return for additional scans. The study also involves neuropsychological tests, which assess cognitive performance. Often, people with mood disorders have subtle changes in performance on these tests that allow researchers to pinpoint where brain abnormalities occur. Before the tests can be used in patients, they must be validated by using healthy subjects. These tests are presented either orally, in written form, or on a computer.