| Conditions: |
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Anxiety Disorders |
| Purpose: |
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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.
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| Study Summary: |
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There have been suggestions that the threshold for amygdala activity is lower in individuals
with anxiety disorders than in healthy individuals. However, despite its 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.
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| Criteria: |
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- INCLUSION CRITERIA:
Age: Participants will be males and females, 18-50 years of age.
IQ: IQ, as measured by 4 subscales from the Wechsler Adult Intelligence Scale-Revised
(WAIS-R), must be greater than 80.
Medication status: No regular use of psychotropic medication within 2 weeks of the study
(or fluoxetine within 8 weeks of the study). No regular use of any benzodiazepine. We
intend to identify patients whose GAD/SAD is currently untreated.
EXCLUSION CRITERIA:
Because factors such as psychiatric disease, or CNS disease, can influence functional
brain activity, and pregnancy precludes participation in fMRI studies, these factors are
exclusionary.
1. Psychiatric history: Participants will be assessed using DSM-IV criteria via
standardized psychiatric interviews conducted by trained examiners (i.e., SCID). Any
current suicidal ideation will be exclusionary.
1. Healthy comparison individuals (Group 1): All participants will be free of any
current psychiatric disorder as well as lifetime history of psychosis, pervasive
developmental disorder, major affective disorder, panic disorder, obsessive
compulsive disorder, ADHD, anorexia.
2. Patients with GAD (Group 2): Any history of an axis I diagnosis including SAD
but not including adjustment disorder, simple phobia or dysthymia is
exclusionary. There must be no current mood disorder (MD) though patients with
past MD, which occurred after the onset of GAD, will be admitted to the study.
3. Patients with SAD (Group 3): Any current history of an axis I diagnosis apart
from GAD and mood disorder (MD) but not including adjustment disorder, simple
phobia or dysthymia is exclusionary. Participants will be excluded if the
patient's MD preceded their SAD. We recognize the difficulty of recruiting
patients with SAD without co-morbid GAD and will therefore allow patients who
are comorbid into the study in this group.
2. History of Drug Abuse: Axis I diagnoses of substance use disorders will be
exclusionary.
3. Severe acute and chronic medical illnesses.
4. CNS disease: History of brain abnormalities (e.g., neoplasms, subarachnoid cysts),
cerebrovascular disease, infectious disease (e.g., abscess), or other neurological
disease, or history of head trauma (defined as a loss of consciousness greater than 3
min).
5. Metal or electronic objects: Metal plates, certain types of dental braces, cardiac
pacemakers, etc., that are sensitive to electromagnetic fields contraindicate MRI
scans.
6. Claustrophobia: Participants will be questioned about potential discomfort in being
in an enclosed space, such as an MRI scanner.
7. Pregnancy status: Because of the potential effects of hormonal changes on brain
function as well as the unknown effects of electromagnetic field on the fetus, known
pregnancy is an exclusion criterion.
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| NCT ID: |
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NCT00062517 |
| Primary Contact: |
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Principal Investigator
Karina S Peschardt, Ph.D.
National Institute of Mental Health (NIMH)
Marilla Geraci, R.N.
Phone: (301) 496-6565
Email: geracim@intra.nimh.nih.gov
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| Backup Contact: |
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N/A |
| Location Contact: |
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Bethesda, Maryland 20892
United States
For more information at the NIH Clinical Center contact Patient Recruitment and Public Liaison Office (PRPL)
Phone: 800-411-1222
Email: prpl@mail.cc.nih.gov
Site Status: Recruiting |