The Role of the Renin-angiotensin System in Reward Reinforcement Learning
试验速览
- 阶段
- 不适用
- 发起方
- 入组人数
- 60
- 试验地点
- 1
- 主要终点
- BOLD-level activity as assessed by fMRI during the learning phase
研究概览
简要总结
This study aims to investigate whether a single dose of losartan (50 mg) can affect learning from positive and negative outcomes and its related neural mechanisms.
详细描述
Emerging evidence suggests that the renin-angiotensin system can impact dopamine (DA) transmission and its modulatory role in reward processing. For instance, recent animal models have found that the angiotensin antagonist losartan reduces rewarding effects of methamphetamine and nicotine by modulating DA release in the striatum.The present study thus will investigate losartan effects on reward reinforcement learning and the underlying neural mechanisms. In a double-blind, between-subject, placebo-controlled design, 60 healthy male subjects will be randomly assigned to receive single-dose losartan (50 mg) or placebo, 90 minutes before performing a probabilistic reinforcement learning task during fMRI.
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
- Double (Participant, Investigator)
入排标准
- 年龄范围
- 18 Years 至 30 Years（Adult）
- 性别
- Male
- 接受健康志愿者
- 是
入选标准
- •Healthy subjects without past or current psychiatric or neurological disorders
- •Right-handedness
- •Normal or corrected-normal version
排除标准
- •History of head injury
- •Medical or psychiatric illness
- •Hypertension
- •General cardio-vascular alteration or diseases
- •Allergy against medications
- •Visual or motor impairments
- •Claustrophobia
- •Drug addiction
- •Nicotine dependence
- •FMRI contradictions
研究组 & 干预措施
Losartan group
Drug: Losartan
干预措施: Losartan (Drug)
Placebo group
Drug: Placebo Oral Tablet
干预措施: Placebo oral tablet (Drug)
结局指标
主要结局
BOLD-level activity as assessed by fMRI during the learning phase
时间窗: 90 minutes to 110 minutes after treatment
During the paradigm subjects will learn the reward properties of stimuli via the presentation of trial-wise feedback. The neural activation during the prediction of positive and negative outcome feedback will be assessed by functional magnetic resonance imaging (fMRI), particularly in prefrontal and subcortical regions. The effects of treatment will be determined by comparing the losartan- and placebo-treated groups.
BOLD-level activity as assessed by fMRI during the learning transfer phase
时间窗: 111 minutes to 120 minutes after treatment
Following the initial learning phase subjects learning transfer will be examined by asking subjects to choose between stimuli with high versus low reward probabilities. The neural activation during correct responses will be assessed by functional magnetic resonance imaging (fMRI), particularly in prefrontal and subcortical regions. The effects of treatment will be determined by comparing the losartan- and placebo-treated groups.
次要结局
- Learning rate for positive and negative outcomes(90 minutes to 110 minutes after treatment)
- Choice accuracy for the stimulus with the high reward probability during the learning phase(90 minutes to 110 minutes after treatment)
- Choice accuracy during the learning transfer phase(111 minutes to 120 minutes after treatment)
研究者
Benjamin Becker
Professor
University of Electronic Science and Technology of China