The Role of the Primate Amygdala in Social and Affective Touch

触摸是我们的第一种情感语言--这种语言让我们能够接收和理解情感 信号和帮助奠定未来社会纽带的基础。尽管人们普遍认为， 触摸在大脑发育和情感和社会沟通的整个生活，显着很少 已知其细胞神经基质。最近的发现表明，皮肤含有 专门用于检测和评估触摸的舒适度。目前还不清楚这些信号是如何 可能在大脑中被处理。然而，很明显，杏仁核是处理大脑中的信号所必需的。 社会和情感意义的感官刺激，无论形式。研究表明这种作用 灵长类动物的杏仁核几乎完全集中在视觉上。最近我们报道了 灵长类杏仁核中的触觉反应神经元。我们将扩大这一初步发现， 这些触觉反应细胞如何对触觉刺激的基本感觉特征做出反应：位置和 强度（目标1）。接下来，我们将确定杏仁核中的触觉细胞是否编码主观的 触摸值（目标2）。鉴于杏仁核在处理社会刺激中的重要作用，我们将 确定触摸的社会维度如何影响触觉细胞的活动（目标3）。具体地说， 我们将同时监测杏仁核和躯体感觉皮层对触摸的神经反应 并比较神经反应相同类型的社会接触，提供给相同的皮肤区域，由两个 与接受者有不同社会经历的人。我们认为触觉细胞 杏仁核，但不是在躯体感觉皮层，区分社会伙伴，支持 杏仁核提取刺激的社会情感维度（价值）。总的来说，这三个 目的提供了一个概念上新的和技术上先进的生理框架， 了解灵长类动物杏仁核如何对触觉刺激做出反应和评估， 主观价值和社会意义。理解情感触摸的细胞机制， 灵长类动物的大脑有望提供重要的见解，为什么触摸处理是如此深刻， 在功能性疼痛综合征、自闭症和许多其他精神疾病中改变。

Touch is our first emotional language – the language that allows us to receive and understand affective signals and help lay the foundation for future social bonds. Despite the widely recognized importance of touch in brain development and in affective and social communication throughout life, remarkably little is known about its cellular neural substrate. Relatively recent discoveries showed that the skin contains specializations for detecting and evaluating the pleasantness of touch. It is unclear how these signals might be processed in the brain. It is clear, however, that the amygdala is required for processing the social and emotional significance of sensory stimuli, regardless of modality. Studies that showed this role of the primate amygdala focused almost exclusively on vision. Recently we have reported the presence of touch-responsive neurons in the primate amygdala. We will expand on this initial finding and determine how these touch-responsive cells respond to the basic sensory features of tactile stimuli: location and intensity (Aim 1). Next, we will determine whether tactile cells in the amygdala encode the subjective value of touch (Aim 2). Given the important role of the amygdala in processing social stimuli, we will then determine how the social dimension of touch factors into the activity of tactile cells (Aim 3). Specifically, we will simultaneously monitor neural responses to touch in the amygdala and somatosensory cortex and compare neural responses to the same type of social touch, delivered to the same skin area, by two individuals with whom the recipient has a different social experience. We expect tactile cells in the amygdala, but not in the somatosensory cortex, to discriminate between social partners, supporting the idea that the amygdala extracts the social-affective dimension (value) of stimuli. Collectively, these three aims provide a conceptually new and technically advanced physiological framework for understanding how the primate amygdala responds to and evaluates tactile stimuli that vary in subjective value and social significance. Understanding the cellular machinery of affective touch in the primate brain is expected to provide important insights into why touch processing is so profoundly altered in functional pain syndromes, autism, and numerous other mental disorders.