Psychobiological mechanisms of impaired reward processing in chronic pain

慢性疼痛奖励处理受损的心理生物学机制

• 批准号: 417307434
• 负责人: Professorin Dr. Susanne Becker
• 金额: --
• 依托单位: Arbeitsgruppe Klinische Psychologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2022-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/417307434?language=en
• 关键词: Psychobiological; mechanisms; impaired; reward; processing

Chronic pain is a major problem causing immense personal suffering and enormous socioeconomic costs. Although pain research has made great progress in the last decades, effective therapy options are still limited. This lack is probably caused by pain research largely focusing on molecular and neuronal mechanisms of nociception (i.e. the neural process of encoding of stimuli that damage or threaten to damage tissues), neglecting multifaceted experiences when being in pain. Recently, the potential etiological and pathogenetic role of emotional-motivational processing when being in pain, going beyond nociceptive processing, has been emphasized. A negative hedonic shift that is mirrored in a shift from nociceptive to emotional-motivational brain circuits has been described in chronic pain. Such a shift is assumed to cause rewarding stimuli as being perceived as less rewarding. However, the currently available data does not allow a conclusion on whether reward processing is truly altered in chronic pain patients and the psychobiological mechanisms of such a shift remain elusive. Providing a conceptual mechanism-oriented framework, the present project aims to characterize alterations in the processing of reward and corresponding neural correlates in patients with chronic pain. For this purpose, 50 patients with chronic back pain and 50 healthy controls will participate each in one functional magnetic resonance imaging (fMRI) and one laboratory session. In the fMRI session, motivation and hedonic experience and corresponding neural correlates related to monetary wins and losses as powerful secondary rewards and punishment and acute pain stimuli as a prototype of aversive stimuli and their avoidance as a rewarding event will be investigated as well as weighting of monetary rewards against avoidance of pain, when both are present concurrently. The laboratory session comprises an assessment of the motivation and hedonic experience of food-related stimuli as potent primary rewards at implicit and explicit levels and a comprehensive clinical assessment. Analysis of behavioral together with imaging data is aimed at testing specifically proposed alterations in brain circuits related to behavioral alterations to close a gap in the available literature. The chosen experimental paradigms allow a specific evaluation and differentiation of alterations in the processing of rewarding stimuli, which have been proposed as underlying the exacerbation of the chronification of pain, including affective comorbidities, thus being important from a theoretical, but also clinical perspective. Expected results will provide a necessary basis for future work, paving the way for exploiting mechanisms related to reward processing that are dysfunctional in chronic pain in mechanism-based interventions for the treatment of chronic pain.

慢性疼痛是一个主要问题，造成巨大的个人痛苦和巨大的社会经济成本。尽管疼痛研究在过去几十年中取得了很大进展，但有效的治疗方法仍然有限。这种缺乏可能是由于疼痛研究主要集中在伤害感受的分子和神经机制（即对损伤或威胁损伤组织的刺激进行编码的神经过程），忽视了疼痛时的多方面体验。最近，潜在的病因和发病机制的作用，情绪动机加工时，在痛苦中，超越伤害性处理，已被强调。在慢性疼痛中描述了一种负面的享乐转变，反映在从伤害性脑回路到情感动机脑回路的转变中。这种转变被认为是导致奖励刺激被认为是奖励较少。然而，目前可用的数据不允许的结论是否奖励处理是真正改变慢性疼痛患者和这种转变的心理生物学机制仍然难以捉摸。提供一个概念性的机制为导向的框架，本项目的目的是表征慢性疼痛患者的奖励和相应的神经相关的处理的改变。为此，50名慢性背痛患者和50名健康对照者将分别参加一次功能性磁共振成像（fMRI）和一次实验室会议。在功能性磁共振成像会议，动机和享乐的经验和相应的神经相关性与金钱的胜利和损失作为强大的二级奖励和惩罚和急性疼痛刺激作为原型的厌恶刺激和他们的回避作为一个奖励事件将被调查，以及加权的金钱奖励对避免疼痛，当两者同时存在。实验室会议包括评估的动机和享乐经验的食物相关的刺激作为潜在的主要奖励在内隐和外显的水平和全面的临床评估。行为与成像数据的分析旨在测试与行为改变相关的脑回路中特别提出的改变，以缩小现有文献中的差距。所选择的实验范式允许一个具体的评价和分化的奖励刺激，这已被提议为潜在的慢性疼痛，包括情感合并症的恶化的处理的改变，因此是重要的从理论上，但也从临床的角度。预期结果将为今后的工作提供必要的基础，为利用机制相关的奖励处理机制，在慢性疼痛的机制为基础的干预措施，治疗慢性疼痛功能失调铺平了道路。