Acute and Chronic Nicotine Modulation of Reinforcement Learning
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 54
- 试验地点
- 1
- 主要终点
- Change in Blood Oxygen Level Dependent (BOLD) Signal in Dorsomedial Prefrontal Cortex
研究概览
简要总结
The purpose of this study is to use functional magnetic resonance imaging (fMRI) to investigate the acute and chronic effects of nicotine on motivational behavior and prediction error-related neural activation. Nonsmokers (n = 24) and smokers (n = 24) will undergo fMRI scans on two separate occasions while performing a decision-making task that will elicit prediction error signals in the mesocorticolimbic pathway of the brain. Nonsmokers will be scanned once following an acute dose of nicotine and once following placebo administration. Smokers will be scanned once following smoking as usual and once following 24-hours of smoking abstinence, in order to measure the effects of nicotine withdrawal. The study team hypothesizes that acute nicotine will increase the prediction error signal in nonsmokers compared to placebo, and that nicotine withdrawal will decrease the prediction error signal in smokers compared to the normal satiated condition. Furthermore, nonsmokers (during the placebo condition) will have greater prediction error activation than smokers (during the satiated condition). The results of this study will inform whether the initiation and maintenance of smoking behavior could be facilitated by the effects of nicotine on reinforcement learning.
研究设计
- 研究类型
- Interventional
- 分配方式
- Non 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 55 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Inclusion criteria for all subjects:
- •generally healthy
- •between the ages of 18-55
- •right-handed
- •Inclusion criteria for nonsmokers:
- •smoked < 50 cigarettes of a brand delivering ≥ 0.5 mg nicotine (FTC method)
- •have not smoked in ≥ 6 months
- •afternoon expired CO concentration ≤ 5 ppm and/or morning urinary NicAlert < 100 ng/ml
- •Inclusion criteria for smokers
- •smoke ≥ 10 cigarettes/day of a brand delivering ≥ 0.5 mg nicotine (FTC method)
- •smoked ≥ 2 years
- •afternoon expired CO concentrations ≥ 10 ppm and/or morning urinary NicAlert > 100 ng/ml
排除标准
- •inability to attend all required experimental sessions
- •significant health problems (e.g., current and uncontrolled liver, lung, or heart problems, current or past seizure disorder, serious head trauma)
- •lifetime diagnosis of Axis I psychiatric disorders (e.g., depression, anxiety disorder, schizophrenia)
- •meet DSM-V criteria for past or current substance dependence other than nicotine
- •use of psychoactive medications as indicated by self-report
- •use of smokeless tobacco, nicotine replacement therapy, or desire to change smoking behavior while in the study
- •positive urine drug screen for illicit drugs or positive breath alcohol concentration
- •presence of conditions that would make MRI unsafe
- •having vision that cannot be corrected to 20/40
- •among women, nursing or a positive pregnancy test
- •inability to achieve learning criteria in training session
研究组 & 干预措施
Nicotine, placebo
Nonsmokers will be measured following a nicotine polacrilex lozenge (2mg) on one occasion and placebo on another occasion.
干预措施: Nicotine polacrilex (Drug)
Nicotine, placebo
Nonsmokers will be measured following a nicotine polacrilex lozenge (2mg) on one occasion and placebo on another occasion.
干预措施: Placebo (Drug)
Nicotine withdrawal or satiety
Smokers will be measured in a normal satiated condition and following 24-hours of smoking abstinence
干预措施: satiety (Other)
Nicotine withdrawal or satiety
Smokers will be measured in a normal satiated condition and following 24-hours of smoking abstinence
干预措施: abstinence (Other)
结局指标
主要结局
Change in Blood Oxygen Level Dependent (BOLD) Signal in Dorsomedial Prefrontal Cortex
时间窗: Nonsmokers: post nicotine and post placebo. Smokers: 24 hours smoking abstinence or smoking satiety
The acute and chronic effects of nicotine on the blood oxygen level dependent signal will be measured using functional magnetic resonance imaging. Reward-cue related BOLD signal on an outcome expectation task.
次要结局
未报告次要终点