Kunwar Prabhat S, Zelikowsky Moriel, Remedios Ryan, Cai Haijiang, Yilmaz Melis, Meister Markus, Anderson David J
Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, United States.
Elife. 2015 Mar 6;4:e06633. doi: 10.7554/eLife.06633.
Defensive behaviors reflect underlying emotion states, such as fear. The hypothalamus plays a role in such behaviors, but prevailing textbook views depict it as an effector of upstream emotion centers, such as the amygdala, rather than as an emotion center itself. We used optogenetic manipulations to probe the function of a specific hypothalamic cell type that mediates innate defensive responses. These neurons are sufficient to drive multiple defensive actions, and required for defensive behaviors in diverse contexts. The behavioral consequences of activating these neurons, moreover, exhibit properties characteristic of emotion states in general, including scalability, (negative) valence, generalization and persistence. Importantly, these neurons can also condition learned defensive behavior, further refuting long-standing claims that the hypothalamus is unable to support emotional learning and therefore is not an emotion center. These data indicate that the hypothalamus plays an integral role to instantiate emotion states, and is not simply a passive effector of upstream emotion centers.
防御行为反映了潜在的情绪状态，如恐惧。下丘脑在这类行为中发挥作用，但主流教科书观点将其描述为上游情绪中枢（如杏仁核）的效应器，而非其本身就是一个情绪中枢。我们运用光遗传学操作来探究介导先天性防御反应的特定下丘脑细胞类型的功能。这些神经元足以驱动多种防御行为，且在不同情境下的防御行为中都是必需的。此外，激活这些神经元所产生的行为后果具有一般情绪状态的特征，包括可扩展性、（负）效价、泛化和持续性。重要的是，这些神经元还能调节习得性防御行为，进一步反驳了长期以来认为下丘脑无法支持情绪学习因而不是情绪中枢的观点。这些数据表明，下丘脑在实现情绪状态方面起着不可或缺的作用，而不仅仅是上游情绪中枢的被动效应器。
