Investigating the effects of VNS on central autonomic network and interoception

摘要 从身体到大脑的内脏传入信息的主要来源是迷走神经。这个 交感神经系统和副交感神经系统是自主神经系统的主要分支。 (ANS)，它们动态地控制内脏功能，以维持身体的动态平衡。ANS的标志 是它对环境挑战/应激源做出反应的能力，以便适当地对代谢需求做出反应 有机体的。据报道，颈迷走神经刺激(VNS)可以调节ANS，特别是心率。 变异性(HRV)和压力反射。然而，实现这些目标的机制仍不清楚。 分离传出调制的直接VNS效应与通过传入的中枢调节的VNS效应 纤维是关键。本补充项目将研究内感觉和内感觉的功能连接模式。 用尖端的脑功能神经成像方法测量的高阶脑区。最重要的是， 它将研究它们与血压和心率自发波动的关系。揭秘共同之处 研究方案(CSP)假设VNS引起的任何血压变化都是通过刺激 迷走神经中的传入(感觉)纤维。这项研究是检验这一假设的另一种选择，并将提供 将补充CSP发现的关键机械数据。通过获取之前的脑功能成像 而在VNS植入后，最关键的是，在对VNS做出反应的时刻，我们可以确定 这种上游中枢神经系统的调节是否处于中脑反射水平，或者它是否涉及 更高级的大脑区域。交错的VNSfMRI将作为VNS即时直接影响的窗口 大脑活动和感觉间的过程。尖端的精密功能映射将可靠地映射 涉及内感和异物同素的多通道网络。

ABSTRACT The principal source of visceral afferent information to the brain from the body is the vagus nerve. The sympathetic and parasympathetic nervous systems are the main branches of the autonomic nervous system (ANS), and they dynamically control the visceral functions to maintain body homeostasis. A hallmark of the ANS is its ability to react to environmental challenges/stressors in order to properly respond to the metabolic demands of the organism. Cervical vagus nerve stimulation (VNS) is reported to modulate ANS and in particular heart rate variability (HRV) and baroreflexes. Yet the mechanisms by which these are achieved remain unknown. Disentangling the direct VNS effects of efferent modulation versus a centrally mediated modulation via afferent fibers is key. This Supplemental Project will investigate the functional connectivity patterns of interoception and high-order brain regions as measured by cutting-edge brain functional neuroimaging methods. Most importantly, it will study their relationship to spontaneous fluctuations in blood pressure and heart rate. The REVEAL Common Study Protocol (CSP) hypothesizes that any VNS-induced changes in blood pressure will be via stimulation of afferent (sensory) fibers in the vagus nerve. This study is an alternative to test this hypothesis and will provide key mechanistic data that will complement discoveries from the CSP. By acquiring functional brain imaging before and after VNS implant and most critically, in the moment activations in response to VNS, we can ascertain whether this upstream central nervous system modulation is at the midbrain reflexive level or whether it involves higher-order brain regions. Interleaved VNSfMRI will act as a window for in-the-moment direct effects of VNS on brain activity and interoceptive processes. The cutting edge precision functional mapping will reliably map the multimodal networks involved in interoception and allostasis.