Improving the Control of Fear: Healthy Adults to Pathological Anxiety
试验速览
- 阶段
- 不适用
- 入组人数
- 40
- 试验地点
- 2
- 主要终点
- Changes in functional magnetic resonance imaging (fMRI)-BOLD (blood-oxygen-level dependent) signal in sensory, prefrontal, and limbic regions during a study on the neurobiology of Pavlovian fear conditioning in humans
研究概览
简要总结
The purpose of this study is to use functional magnetic resonance imaging to investigate how the human brain learns to form associations between neutral and emotional stimuli. The study is based on the basic principles of Pavlovian conditioning.
When someone learns that a neutral stimulus (such as the sound of a bell) predicts an unpleasant stimulus (such as a mild electrical shock), the neutral stimulus takes on the properties of an emotional stimulus.
The investigators are interested in the neural processes involved in this learning in people with a clinical anxiety disorder and posttraumatic stress disorder (PTSD).
详细描述
This study uses functional MRI in people with anxiety and stress-related disorders to evaluate the neural correlates of fear conditioning and extinction. During fear conditioning participants see a picture of a face that predicts a mild electrical shock to the wrist. Participants then return the next day to the scanner for a test of fear expression 24-hours after fear conditioning. The investigators are simultaneously measuring autonomic arousal in the scanner using measures of skin conductance responses (i.e., sweating).
The primary objective of this study is to evaluate different forms of Pavlovian fear extinction in patients who suffer from pathological anxiety. The investigators are interested in the effects of extinction and extinction retention over a delay in regions that are known to show abnormalities in anxiety populations. This includes the amygdala, ventromedial prefrontal cortex, and the hippocampus.
The study is testing behavioral strategies and does not include any pharmacological manipulations.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Basic Science
- 盲法
- Single (Participant)
入排标准
- 年龄范围
- 18 Years 至 50 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Male or female volunteer aged 18-50 years old
- •Able to understand procedures and agree to participate in the study by giving written informed consent.
- •Speaks fluent English.
- •Not taking illicit drugs.
- •No history of neurological problems.
- •Eligible for MRI, including no metal in the body or body piercings that cannot be removed.
排除标准
- •Current comorbid Axis 1 psychiatric disorder
- •Women who are current pregnant or breastfeeding
- •Lifetime diagnosis of any psychotic disorder, cognitive suicidal ideation, substance abuse or alcohol dependence, hoarding.
- •Medications that act on the central nervous system that interfere with interpretation of the findings (e.g., painkillers, Adderall)
- •Claustrophobia
- •Patients who are unable to comply with procedures or assessments.
研究组 & 干预措施
Novelty facilitated extinction
Behavioral intervention. After Pavlovian fear conditioning, the shock is omitted and replaced by a novel, surprising, and neutral auditory tone.
干预措施: Novelty facilitated extinction (Behavioral)
Standard extinction
The shock is omitted during standard extinction
干预措施: Standard Extinction (Behavioral)
结局指标
主要结局
Changes in functional magnetic resonance imaging (fMRI)-BOLD (blood-oxygen-level dependent) signal in sensory, prefrontal, and limbic regions during a study on the neurobiology of Pavlovian fear conditioning in humans
时间窗: Only on the day of the experiment
We are measuring increases in the BOLD signal in response to visual stimuli during a Pavlovian conditioning task in humans.
次要结局
- Skin conductance responses evoked during a Pavlovian fear conditioning task in humans as an index of physiological arousal.(Only on the day of the experiment)