Generalized Anxiety Disorder and Social Anxiety Disorder: Their Impact on the Processing of Information and Learning
Condition: Anxiety Disorders
MeSH terms: Anxiety Disorders; Phobia, Social
Study type: Observational

Summary: 
      The purpose of this study is to increase researchers understanding of the biological basis of
      generalized anxiety disorder and social anxiety disorder. They will investigate how the brain
      activity associated with specific thoughts and feelings may play a role in these anxiety
      disorders. This knowledge will be used to design interventions to help those with these
      illnesses.

      To qualify for this study, participants must be evaluated via an initial telephone screening
      interview and material sent through the mail.

      Participants will then be required to make three visits to NIH. During the first visit, they
      will be asked questions about their general mood, degree of nervousness, thinking skills, and
      behavior. They will undergo a thorough physical exam, including an EKG, blood work,
      urinalysis, and a pregnancy test for women of childbearing potential. During the second
      visit, participants will spend about 2.5 hours doing various tasks while sitting and looking
      at a computer screen. These tasks will guide them to experience specific kinds of thoughts
      and emotions. Researchers will attach electrodes to the participants hands to monitor the
      amount of electricity conducted by the skin. The third visit will be similar to the second
      visit, but participants will perform the tasks while lying in a MRI scanner.

      Participants will be compensated up to $400 for their involvement in this study.
    

Detailed description: 
      There have been suggestions that the threshold for amygdala activity is lower in individuals
      with anxiety disorders than in healthy individuals. However, despite it's immediate
      plausibility, there have been relatively few tests of this hypothesis. Specifically, there
      have been very few explorations of the performance of patients with anxiety disorders on
      measures known to implicate the amygdala.

      Although the high co-morbidity of Generalized Anxiety Disorder (GAD) and Social Anxiety
      Disorder (SAD) complicates the issue, the fact that the disorders doubly dissociate suggests
      that they are due to dysfunctional activity in separable neurocognitive systems. We would
      suggest that the hyper-responsive amygdala hypothesis is more likely to be linked to the
      explanation of GAD. In contrast, SAD may be due to reduced activation thresholds for units in
      a system that responds to social threat and which recruits lateral orbital frontal cortex.
      Thus, the current project will determine the performance of patients with GAD and SAD on
      measures in which the amygdala is known to play a role and also measures that recruit lateral
      orbital frontal cortex and the system for social response reversal. In addition, two proposed
      neuro-imaging studies will directly assess neural responses in these two systems in both
      patient populations. The project should provide clear data that will constrain future
      theorizing on the pathology implicated in these two disorders.
    

Observational model: Cohort
Time perspective: Prospective
Keywords: Amygdala; Generalized Anxiety Disorder; Anxiety Disorder; GAD; Social Anxiety Disorder; SAD