Non-invasive assessment and modulation of brain-gut interoception in humans

项目摘要/摘要 内感是指生物体内部状态的表征，包括通过 它感知、解释、整合和调节来自自身内部的信号。内隐感觉越来越多 被视为大脑和身体之间的双向过程，在这个过程中，多重反馈和前馈 循环导致身体的内部表示。迷走神经与自主神经密切相关。 控制上胃肠道(GI)，向延髓脑干核团投射。反过来, 内感通路也可以直接靶向于临床有益的神经调节和非侵入性 与脑干迷走神经回路相互作用的神经调节技术，包括经皮耳穴 迷走神经刺激(TaVNS)，已被报道通过 孤束核接合(NTS)。然而，更广泛地了解taVNS对胃的影响 胃间感觉信号的功能和大脑反应是必要的，并且需要工具来直接探测 人类的肠道-脑轴。在我们的研究中，我们将结合一个完全无创的实验框架，包括 胃和脑磁共振成像(MRI)与校准进食和MRI- 相容的tavns以评估内脏内知觉沿脑-肠轴的调节。目标1将 评估校准餐后胃功能和大脑对胃间感觉信号的反应 摄取。在目标2中，我们将研究tavns对胃功能和大脑对胃的反应的调节。 感觉间的信号。这项拟议的研究将为双向肠脑提供新的见解。 胃内感觉的相互作用及其通过非侵入性神经调节技术的调节 它们专门针对内感通路(即taVNS)。

PROJECT SUMMARY/ABSTRACT Interoception refers to the representation of the internal states of an organism, and includes the processes by which it senses, interprets, integrates, and regulates signals from within itself. Interoception is increasingly viewed as a bidirectional process between the brain and body, in which multiple feedback and feedforward loops lead to an internal representation of the body. The vagus nerve is intimately involved in autonomic control of the upper gastrointestinal (GI) tract, with afferent projections to medullary brainstem nuclei. In turn, interoceptive pathways can also be directly targeted for clinically beneficial neuromodulation and non-invasive neuromodulatory techniques that interact with brainstem vagal circuitry, including transcutaneous auricular vagal nerve stimulation (taVNS), have been reported to modulate efferent visceral vagal pathways via the engagement of nucleus tractus solitarii (NTS). However, broader understanding of taVNS effects on gastric function and brain response to gastric interoceptive signaling is needed, and requires tools to directly probe the gut-brain axis in humans. In our study, we will combine a fully non-invasive experimental framework including sequential gastric and brain Magnetic Resonance Imaging (MRI) with calibrated meal ingestion and MRI- compatible taVNS to evaluate the modulation of visceral interoception along the brain-gut axis. Aim 1 will evaluate gastric function and brain response to gastric interoceptive signaling following calibrated meal ingestion. In Aim 2, we will then investigate taVNS modulation of gastric function and brain response to gastric interoceptive signaling. The proposed study will contribute new insights into the bidirectional gut-brain interaction underlying gastric interoception, and its modulation via non-invasive neuromodulatory techniques that specifically target interoceptive pathways (i.e. taVNS).