Expectation of Unpleasant Events in Anxiety Disorders
|First Received Date ICMJE||February 21, 2003|
|Last Updated Date||May 3, 2013|
|Start Date ICMJE||February 2003|
|Primary Completion Date||Not Provided|
|Current Primary Outcome Measures ICMJE||Not Provided|
|Original Primary Outcome Measures ICMJE||Not Provided|
|Change History||Complete list of historical versions of study NCT00055224 on ClinicalTrials.gov Archive Site|
|Current Secondary Outcome Measures ICMJE||Not Provided|
|Original Secondary Outcome Measures ICMJE||Not Provided|
|Current Other Outcome Measures ICMJE||Not Provided|
|Original Other Outcome Measures ICMJE||Not Provided|
|Brief Title ICMJE||Expectation of Unpleasant Events in Anxiety Disorders|
|Official Title ICMJE||Predictability and Aversive Expectancies in Anxiety and Depressive Disorders|
Fear and anxiety are normal responses to a threat. However, anxiety is considered abnormal when the response to the threat is excessive or inappropriate. This study will examine changes in the body and brain that occur during unpleasant learning experiences in healthy volunteers with high, moderate, and low levels of anxiety.
A high degree of generalized anxiety is a component of many anxiety disorders and is regarded as a marker of vulnerability for these disorders. People with anxiety disorders and individuals with high degrees of anxiety have inappropriate expectations of unpleasant events. This study will investigate the development of expecting unpleasant events in healthy volunteers with varying degrees of anxiety using aversive conditioning models. A later phase of the study will enroll participants with anxiety disorders and compare their responses to those of healthy volunteers.
Patients who meet criteria for an anxiety disorder, and healthy volunteers who have no history of psychiatric or major medical illness will be enrolled in this study. Volunteers will come to the NIH Clinical Center three times for outpatient testing.
High-generalized anxiety is a concomitant of many anxiety disorders and is often regarded as a vulnerability marker for these disorders. One characteristic of patients with anxiety disorders and high trait-anxious individuals is inappropriate expectancies of aversive events. The overall aim of the present protocol is to investigate mechanisms that may promote the development of these aversive expectancies using expectancy-based, associative-learning models.
During aversive conditioning in which a phasic explicit-cue (e.g., a light) is repeatedly associated with an aversive unconditioned-stimulus (e.g., a shock), the organism develops fear to the explicit cue as well as to the environmental context in which the experiment took place. We have obtained preliminary evidence suggesting that contextual fear represents aspects of aversive states that are central to anxiety disorders. In this protocol, we seek further evidence for the relevance of contextual fear to mood anxiety disorders.
One important determinant of contextual fear in both humans and animals is predictability: contextual fear increases when aversive events (e.g., electric shock) are unpredictable, as opposed to when they are predictable. The present protocol will examine the role of predictability of aversive states and of conditioning on threat appraisal in anxious individuals.
A second aim is to examine processes that may promote the development of contextual fear. Classical aversive-conditioning is an ideal technique to explore cognitive, attentional, and emotional processes underlying the development of aversive expectations to explicit and contextual cues. We will attempt to relate conditioned performance to measures of 1) autonomic reactivity (orienting response and heart-rate variability) and 2) attentional bias. Substantial evidence suggests that autonomic reactivity has broad implication for cognitive and affective regulation and that attentional biases may imply a role in generating and/or maintaining maladaptive levels of anxiety.
A third aim is to use socially-relevant stimuli to examine fear and anxiety in social anxiety disorders. These include a speech stressor given in a virtual reality environment and using faces as conditioned stimuli and social words in a classical conditioning experiment.
Finally, given the high comorbidity between anxiety and depression, a last aim is to examine the role fo depression on these measures of fear and anxiety.
|Study Type ICMJE||Observational|
|Study Design ICMJE||Not Provided|
|Target Follow-Up Duration||Not Provided|
|Sampling Method||Not Provided|
|Study Population||Not Provided|
|Condition ICMJE||Anxiety Disorders|
|Intervention ICMJE||Not Provided|
|Study Group/Cohort (s)||Not Provided|
* Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
|Recruitment Status ICMJE||Recruiting|
|Estimated Enrollment ICMJE||1041|
|Completion Date||Not Provided|
|Primary Completion Date||Not Provided|
|Eligibility Criteria ICMJE||
Inclusion criteria for both patients and healthy controls:
Exclusion criteria for healthy subjects:
Exclusion criteria for patients:
|Ages||18 Years to 60 Years|
|Accepts Healthy Volunteers||Yes|
|Location Countries ICMJE||United States|
|NCT Number ICMJE||NCT00055224|
|Other Study ID Numbers ICMJE||030093, 03-M-0093|
|Has Data Monitoring Committee||Not Provided|
|Responsible Party||Not Provided|
|Study Sponsor ICMJE||National Institute of Mental Health (NIMH)|
|Collaborators ICMJE||Not Provided|
|Information Provided By||National Institutes of Health Clinical Center (CC)|
|Verification Date||January 2013|
ICMJE Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP