A novel output pathway from the cerebellum for regulation of diverse non-motor behaviors

摘要/概要 除了在运动功能和运动学习中的既定作用外，小脑还参与了一种运动神经元的活动。 无数的非运动行为。在人类中，小脑损伤会损害抽象推理和工作能力， 导致创伤后应激障碍在动物模型中，小脑调节心率，呼吸，攻击性， 食欲，恐惧条件反射和许多其他行为。总的来说，小脑在调节这些神经元中的作用， 行为不太清楚。理解这些非运动行为的一个重要步骤是确定 输出通路和下游目标，使小脑调节这些行为。已知 浦肯野细胞（PC）将信号从小脑皮质传递到小脑深核（DCN）， 激活运动丘脑假设DCN输出也负责非电机 行为。在这里，我们描述了强大的和直接的抑制性连接之间的PC的区域， 小脑参与非运动行为，臂旁核（PBN）中的神经元。这是 有趣的是，因为PBN有助于许多相同的非运动行为的影响， 小脑基于我们的初步发现，我们假设PBN是一个专门的小脑输出 使小脑能够调节非运动行为。检验这一假设的第一步是 描述PC和PBN之间的连接。这些研究将确定强度和 直接PC到PBN突触的流行率，并确定PC调节PBN活性的程度。 PBN中的神经元。第二个主要步骤是鉴定PC β PBN途径靶向的区域， 确定这条通路对各种行为的贡献。初步研究表明， 投射到下丘脑、杏仁核和基底前脑，因此具有适当的连接性。 使小脑能够调节从攻击到恐惧消失的各种行为。这承诺 为了对小脑在许多行为中的作用有一个新的认识，它将提供对以下方面的深入了解： 参与这些行为的回路，它对许多神经系统疾病有重要意义。

Abstract/Summary In addition to its well-established role in motor function and motor learning, the cerebellum is implicated in a myriad of non-motor behaviors. In humans, cerebellar damage can impair abstract reasoning and working memory, and result in PTSD. In animal models, the cerebellum regulates heart rate, breathing, aggression, appetite, fear conditioning and many other behaviors. In general, the role of the cerebellum in regulating these behaviors is not well understood. An important step in understanding these nonmotor behaviors is to determine the output pathway and downstream targets that allow the cerebellum to regulate these behaviors. It is known that Purkinje cells (PCs) relay signals from the cerebellar cortex to the deep cerebellar nuclei (DCN), which in turn activate the motor thalamus. It was assumed that DCN outputs are also responsible for nonmotor behaviors. Here, we describe powerful and direct inhibitory connections between PCs in regions of the cerebellum implicated in nonmotor behaviors, and neurons in the parabrachial nucleus (PBN). This is intriguing, because the PBN contributes to many of the same nonmotor behaviors influenced by the cerebellum. Based on our preliminary findings, we hypothesize that the PBN is a specialized cerebellar output that allows the cerebellum to regulate nonmotor behaviors. The first step in testing this hypothesis will be to characterize the connections between PCs and the PBN. The studies will determine the strength and prevalence of the direct PC to PBN synapse and determine the extent to which PCs regulate the activity of neurons in the PBN. The second major step is to identify the regions targeted by the PCPBN pathway and to determine the contribution of this pathway to various behaviors. Preliminary studies suggest that this pathway projects to the hypothalamus, the amygdala, and the basal forebrain, and thus has the appropriate connectivity to allow the cerebellum to regulate diverse behaviors ranging from aggression to fear extinction. This promises to lead to a new appreciation of the roles of the cerebellum in numerous behaviors, it will provide insight into the circuits involved in these behaviors and it has important implications for many neurological disorders.