A PET & fMRI study on opioid conditioning (placebo) effects

描述(申请人提供)：止痛是最有力和研究最好的安慰剂效果之一。越来越多的证据表明，存在一系列安慰剂止痛机制。最近的神经成像研究表明，多个脑区和神经递质参与其中。然而，目前尚不清楚这些实验的结果是否代表了安慰剂效应的一般模式，还是由特定情况引发的多种不同的机制。绘制连贯和精确的路径图(S)是安慰剂研究中的一个紧迫挑战。这项研究的目的是产生初步的创新的、高空间分辨率的、同时的、多模式的脑成像数据，研究特定神经递质系统中精确定义的安慰剂止痛效果和BOLD磁共振成像所反映的整个大脑活动。具体地说，基于依赖于吗啡调节的安慰剂效应是可逆的证据，这项建议将使用创新技术--可以同时收集功能磁共振成像和[11C]卡芬太尼PET数据的MRI-PET系统--来研究阿片(吗啡)调节效应的大脑机制。我们相信这项研究(结合未来计划的一项扩展研究)将在更一般的水平上扩大我们对药物特定的条件反射效应、成瘾、身心互动以及认知(有意识)和非认知(无意识)调制过程的理解。 公共卫生相关性：这项研究的目的是利用MRI和PET相结合的创新成像技术来研究阿片类药物(吗啡)安慰剂效应的潜在机制。

DESCRIPTION (provided by applicant): Analgesia is one of the most robust and best-studied placebo effects. Accumulated evidence indicates the existence of a spectrum of placebo analgesia mechanisms. Recent neuroimaging studies have demonstrated the involvement of multiple brain regions and neurotransmitters. Yet it is still unclear if the results from these experiments represent a general modality of the placebo effect or multiple distinct mechanisms elicited by specific situations. Mapping coherent and precise pathway(s) is an urgent challenge in placebo studies. The aim of this study is to generate preliminary innovative, high spatial resolution, simultaneous, multi-modal brain imaging data investigating precisely defined placebo analgesic effects in specific neurotransmitter system and whole brain activity as reflected by BOLD MR imaging. Specifically, based on evidence that placebo effects dependent on morphine conditioning are naloxone reversible, this proposal will investigate the brain mechanism of opioid (morphine) conditioning effects using innovative technology -- an integrated MRI-PET system that can collect fMRI and [11C] carfentanil PET data simultaneously. We believe this study (combined with an extended study planned for the future) will expand our understanding of drug-specific conditioning effects, addiction, mind-body interaction, and cognitive (conscious) and non-cognitive (unconscious) modulation processes on a more general level. PUBLIC HEALTH RELEVANCE: The aim of this study is to investigate the underlying mechanism of opioid (morphine) placebo effects using the innovative imaging technique of integrated MRI and PET.