Iglesias Amanda G, Flagel Shelly B
Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI, United States.
Michigan Neuroscience Institute, University of Michigan, Ann Arbor, MI, United States.
Front Integr Neurosci. 2021 Jun 18;15:706713. doi: 10.3389/fnint.2021.706713. eCollection 2021.
In this review, we highlight evidence that supports a role for the paraventricular nucleus of the thalamus (PVT) in motivated behavior. We include a neuroanatomical and neurochemical overview, outlining what is known of the cellular makeup of the region and its most prominent afferent and efferent connections. We discuss how these connections and distinctions across the anterior-posterior axis correspond to the perceived function of the PVT. We then focus on the hypothalamic-thalamic-striatal circuit and the neuroanatomical and functional placement of the PVT within this circuit. In this regard, the PVT is ideally positioned to integrate information regarding internal states and the external environment and translate it into motivated actions. Based on data that has emerged in recent years, including that from our laboratory, we posit that orexinergic (OX) innervation from the lateral hypothalamus (LH) to the PVT encodes the incentive motivational value of reward cues and thereby alters the signaling of the glutamatergic neurons projecting from the PVT to the shell of the nucleus accumbens (NAcSh). The PVT-NAcSh pathway then modulates dopamine activity and resultant cue-motivated behaviors. As we and others apply novel tools and approaches to studying the PVT we will continue to refine the anatomical, cellular, and functional definitions currently ascribed to this nucleus and further elucidate its role in motivated behaviors.
在本综述中，我们着重介绍支持丘脑室旁核（PVT）在动机行为中发挥作用的证据。我们涵盖了神经解剖学和神经化学概述，概述了该区域的细胞组成及其最主要的传入和传出连接。我们讨论了这些连接以及沿前后轴的差异如何与PVT的感知功能相对应。然后，我们聚焦于下丘脑-丘脑-纹状体回路以及PVT在该回路中的神经解剖学和功能定位。在这方面，PVT处于理想位置，能够整合有关内部状态和外部环境的信息，并将其转化为动机行为。基于近年来出现的数据，包括我们实验室的数据，我们认为从下丘脑外侧区（LH）到PVT的食欲素能（OX）神经支配编码奖励线索的激励动机价值，从而改变从PVT投射到伏隔核壳（NAcSh）的谷氨酸能神经元的信号传递。PVT-NAcSh通路随后调节多巴胺活性以及由此产生的线索驱动行为。随着我们和其他研究人员应用新工具和方法来研究PVT，我们将继续完善目前赋予该核团的解剖学、细胞和功能定义，并进一步阐明其在动机行为中的作用。
