Dynamic Evaluation of Neural Mechanisms for Affective Touch: Pathways for Touch-induced Pleasantness and Pain Modulation

情感触摸神经机制的动态评估：触摸引起的愉悦感和疼痛调节的途径

• 批准号: 10660199
• 负责人: Laura K Case
• 金额: $ 69.02万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-03 至 2028-02-29
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10660199
• 关键词: Ablation; Address; Adult; Affective; Afferent Pathways; Amyloid beta-Protein; Anterior; Anterolateral; Area; Brain; Brain imaging; C Fiber; Central Nervous System; Clinical; Complementary therapies; Complex; Cordotomy; Data; Deafferentation procedure; Dedications; Dependence; Disease; Esthesia; Evaluation; Fiber; Functional Magnetic Resonance Imaging; Goals; Health; Impairment; Individual; Individual Differences; Insula of Reil; Interneurons; Left; Light; Local Anesthetics; Machine Learning; Manipulative Therapies; Maps; Massage; Measures; Methods; Mind-Body Intervention; Mission; National Center for Complementary and Integrative Health; Nerve Fibers; Nerve compression syndrome; Neural Pathways; Nociceptors; Outcome; Pain; Pain management; Parasympathetic Nervous System; Pathway interactions; Patients; Peripheral; Process; Public Health; Relaxation; Relaxation Therapy; Research; Research Personnel; Role; Signal Transduction; Skin; Somatosensory Cortex; Spinal; Strategic Planning; Stroke; Study Subject; Tactile; Temperature Sense; Testing; Time; Touch sensation; Vertebral column; chronic pain; cingulate cortex; heart rate variability; individual response; innovation; mechanotransduction; neuromechanism; neuroregulation; novel; pain reduction; pain relief; predictive modeling; preference; preservation; pressure; response; secondary outcome; theories; tool; volunteer

Project Summary/Abstract The exact mechanisms by which light stroking and deep pressure – components of massage therapy – induce pleasantness and pain modulation are not understood. Given the frequent use of massage therapy for relaxation and pain relief, and the need for complementary tools for chronic pain, there is a critical need to study the mechanisms of specific forms of affective touch. Our long-term goal is to elucidate the mechanisms by which manual therapies induce pleasant relaxation and pain relief. Our overall objectives in this application are to (1) Determine the extent to which A- and C-fibers contribute to affective effects of gentle stroking, 2) Determine the extent to which A- and C-fibers contribute to affective effects of deep pressure, and 3) Determine the contribution of C-fibers to neural mechanisms of touch-induced pleasantness and pain modulation. We will also (Exploratory) use machine learning to identify individual contributions of C-tactile (CT) fibers to neural mechanisms of touch pleasantness and pain modulation, and the association of interoceptive sensibility with CT effects. Our central hypothesis is that A-fibers are necessary but not sufficient for the pleasantness of gentle stroking and unnecessary for its pain reduction, but are necessary and sufficient for the pleasantness and pain reduction of deep pressure. Further, we hypothesize that left anterior insula and anterior cingulate cortex activation will predict CT contributions to modulation of pain by touch. We will conduct a two session within-subject study in healthy adult volunteers to test the effects of A- and C-fiber blockade on the pleasantness and pain modulation induced by slow stroking (N = 24) and deep pressure (N = 24). We will then test effects of A-fiber blockade on brain mechanisms of pain modulation during fMRI, and relationships between CT contributions and touch pleasantness, pain modulation, and interoceptive sensibility (N = 36). Effects of CT inputs on heart rate variability will comprise a secondary outcome. Upon successful completion of the proposed research, we expect to have identified the role of A- and C-fibers in the pathways and major effects of affective touch. This contribution is expected to be significant because it will define the pathways for two major forms of affective touch and their effects on pain, providing reliable information about non-invasive measures for pain control and potential targets for noninvasive neuromodulation of pain. Further, this project is innovative because it explores a novel affective touch pathway, applies a novel method to causally test afferent pathways for affective touch, and uses machine learning to explore individual differences in the contributions of CTs to neural mechanisms for affective touch. Our proposed project seeks to elucidate pathways for two major forms of affective touch commonly engaged by massage. This research will have a positive impact by opening new horizons for mechanistic research on effects of touch in health and disease, and may provide targets for neuromodulation in the treatment of pain.

项目概要/摘要 轻抚和深压（按摩疗法的组成部分）诱发的确切机制 鉴于经常使用按摩疗法来放松，愉悦感和疼痛调节尚不清楚。 和缓解疼痛，以及对慢性疼痛补充工具的需求，迫切需要研究 我们的长期目标是阐明特定形式的情感触摸的机制。 手动疗法可带来愉快的放松和疼痛缓解，我们在此应用中的总体目标是 (1) 确定 A 纤维和 C 纤维对轻柔抚摸的情感影响的程度，2) 确定 A 纤维和 C 纤维对深层压力的情感影响的贡献程度，以及 3) 确定贡献 我们还将（探索性）研究 C 纤维与触摸引起的愉悦感和疼痛调节的神经机制。 使用机器学习来识别 C 触觉 (CT) 纤维对触觉神经机制的个体贡献 愉悦感和疼痛调节，以及内感受性与 CT 效应的关联。 假设 A 纤维是必要的，但对于轻柔抚摸和抚摸的愉悦感来说还不够。 对于减轻疼痛来说是不必要的，但是对于减轻疼痛和愉悦感来说是必要和充分的 此外，我们还发现左前岛叶和前扣带皮层的激活可以预测。 CT 对通过触摸调节疼痛的贡献 我们将在健康人群中进行为期两次的受试者内研究。 成年志愿者测试 A 纤维和 C 纤维阻断对愉悦感和疼痛调节的影响 通过缓慢抚摸（N = 24）和深度压力（N = 24），我们将测试 A 纤维阻断对大脑的影响。 fMRI 期间疼痛调节的机制，以及 CT 贡献和触觉之间的关系 CT 输入对心率变异性的影响。 成功完成拟议的研究后，我们预计将包括次要成果。 确定了 A 纤维和 C 纤维在情感触摸的途径和主要影响中的作用。 预计意义重大，因为它将定义情感触摸的两种主要形式及其影响的途径 对疼痛的影响，提供有关疼痛控制的非侵入性措施和潜在目标的可靠信息 此外，该项目具有创新性，因为它探索了一种新颖的情感。 触摸通路，应用一种新颖的方法来因果测试情感触摸的传入通路，并使用机器 学习探索 CT 对情感触觉神经机制贡献的个体差异。 我们提出的项目旨在阐明两种主要形式的情感接触的途径 这项研究将为效果机制研究开辟新视野，从而产生积极影响。 触摸在健康和疾病中的作用，并可能为治疗疼痛的神经调节提供目标。