Neural mechanisms linking memory and interoception

动机和背景。在心理学和神经科学中有一个新兴的共识，即传入内脏信号形成主观感觉状态的核心元素。在揭示内脏反馈感知的大脑机制方面已经取得了重大进展，这一过程被称为内感受。来自多种神经影像学方式的证据表明，岛叶皮层在内感受中发挥着核心作用，并且还将其与嵌入了岛叶的大规模网络中的相互作用联系起来。几乎所有关于内感受在行为中的作用的研究都集中在情绪上。然而，有人认为，它可以发挥更广泛的功能作用，甚至可以扩展到认知和意识领域，即使是对没有任何情感内容的刺激。鉴于在记忆判断过程中可能出现的感觉状态的丰富文献（例如，熟悉感、似曾相识感、知晓感），我们最近开始研究内脏反馈和内感受在记忆判断中的潜在作用，并获得了非常有希望的第一批心理生理学发现。我的研究计划的总体目标是增加对记忆判断所涉及的各种机制的理解，特别关注下一步内脏反馈的影响。在拟议的研究计划中，我们计划采用多模态认知神经科学方法来实现这一目标。它集中在心脏反馈在与特定感觉状态相关的记忆决策和元记忆判断中的作用。指导我们研究的一个中心思想是，内脏反馈通过大脑的内感受机制来塑造这些记忆决策和体验。为了验证这一观点，我们将采用脑电图记录来检查皮层心跳诱发电位的作用，并使用MRI来阐明前额叶的功能作用，以及它与其他皮层结构的功能相互作用，在这种记忆判断中。这项研究计划的发现有望为记忆判断和相关感受的机械解释奠定基础，该解释将身体状态的皮质表征与其他已知的塑造记忆的神经表征联系起来。从神经解剖学的角度来看，这项工作将揭示功能的贡献和相互作用的大脑结构，经常被激活的功能磁共振成像研究的记忆，但很少讨论。通过强调身体和主观经验的作用，我们的研究结果也将说明，在当今的数字社会中，人类代理人做出的记忆决定与虚拟知识工具提供的记忆决定最终可能会有什么不同。

MOTIVATION AND BACKGROUND. There is an emerging consensus in psychology and neuroscience that afferent visceral signals form a core element of subjective feeling states. Significant progress has been in made in revealing the brain mechanisms that underlie the perception of visceral feedback, a process known as interoception. Evidence from multiple neuroimaging modalities points to a central role of the insular cortex in interoception, and it also links it to interactions in large-scale networks in which the insula is embedded. Almost all research on the role of interoception in behavior has focused on emotion. There are suggestions, however, that it could play a much broader functional role, extending into the domains of cognition and consciousness even for stimuli without any affectively-laden content. Given the rich documentation of feeling states that can arise during memory judgements (e.g., familiarity, déjà vu, feelings-of-knowing), we have recently started to examine a potential role for visceral feedback and interoception in memory judgements, with very promising first psychophysiological findings.OBJECTIVES AND GENERAL APPROACH. The overarching goal of my research program is to increase understanding of the full range of mechanisms involved in making memory judgments, with a special focus on the influence of visceral feedback in the next step. In the proposed research program, we plan to pursue this goal with a multi-modal cognitive neuroscience approach. It centers on the role of cardiac feedback in recognition-memory decisions and meta-memory judgements that are tied to specific feeling states. A central idea that will guide our research is that visceral feedback shapes these memory decisions and experiences through brain mechanisms of interoception. To test this idea, we will employ EEG recordings for examination of the role of the cortical heartbeat evoked potential, and use MRI to elucidate the functional role of the anterior insula, and its functional interactions with other cortical structures, in such memory judgements.IMPACT. The findings from this research program are expected to set the stage for a mechanistic account of memory judgments and associated feelings that considers the cortical representations of bodily states in relation to other neural representations that are known to shape memory. From a neuroanatomical perspective, this work will shed light on functional contributions and interactions of a brain structure that is frequently activated in fMRI studies on memory but rarely discussed. By emphasizing the role of the body and of subjective experience, our findings will also speak to what may ultimately distinguish memory decisions made by human agents from those that can be offered by virtual knowledge tools in today's digital society.