Getting Excited About Learning.
Getting Excited About Learning.
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对学习感到兴奋。
DOI：
10.1093/function/zqab059
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Matikainen-Ankney,Bridget
中科院分区：
文献类型：
--
作者：
Matikainen-Ankney,Bridget
运动学习被认为涉及增加背外侧纹状体(DLS)谷氨酸能输入的突触强度，增强纹状体的活动和激励特定的行动。然而，支配这种突触强度变化的细胞类型仍然未知。纹状体包括两种主要的细胞类型，即直接通路神经元和间接通路神经元(dSPN和iSPN)，以及多种类型的中间神经元。一个“经典”的基底节功能模型预测，dSPN和iSPN在动作产生过程中相互对立，dSPN激励动作，iSPN反对竞争或干扰动作。2然而，较新的基础神经节功能模型指出，dSPN和iSPN在动作和动作准备过程中都被激活，3这导致了这些类型的细胞以互补或竞争的方式共同工作以控制运动的提议。4这里，有一组令人印象深刻的清醒小鼠的电生理记录，Sippy等人。进一步了解这些模型，以及突触输入到特定纹状体细胞类型在运动学习后是如何变化的。5使用活体全细胞记录来监测感觉-运动-联想任务中单个DLS神经元的膜电压。作者使用了一个磁线圈和一个小金属珠来偏转老鼠的一根胡须，这表明有水可用。他们在受过训练的小鼠身上进行了测试，这些小鼠已经学会了将胡须偏转与水的可获得性联系起来，并在这种偏转后不久开始舔食。他们发现，dSPN和iSPN都对这种胡须刺激做出了去极化的反应，dSPN表现出比iSPN更快的去极化。这种方法提供了直接的电生理学证据，将这种习得的运动动作与兴奋性突触输入到DLS联系起来，并增加了我们对突触输入如何驱动的理解
Motor learning is thought to involve an increase in the synaptic strength of glutamatergic inputs to the dorsolateral striatum (DLS), enhancing striatal activity and invigorating specific actions. 1 However, the cell types that govern this change in synaptic strength remain unknown. The striatum comprises two principal cell types, known as direct and indirect pathway neurons (dSPNs and iSPNs), as well as multiple classes of interneurons. A “classic” model of basal ganglia function predicts that dSPNs and iSPNs oppose one another during action generation, with dSPNs invigorating actions and iSPNs opposing competing or interfering actions. 2 However, more recent models of basal ganglia function have noted that both dSPNs and iSPNs are activated during actions and action preparation, 3 leading to proposals that these cell types work together in a complementary or competitive manner to govern movement. 4 Here, with an impressive set of electrophysiological recordings in awake mice, Sippy et al. further our understanding of these models, and of how synaptic inputs onto specific striatal cell types change following motor learning.Previously in 2015, Sippy et al. 5 used whole cell in vivo recordings to monitor membrane voltages of individual DLS neurons in a sensorimotor-association task. The authors used a magnetic coil and a small metal bead to deflect a single whisker of the mice, which signaled the availability of water. They tested this in trained mice that had learned to associate the whisker deflection with the availability of water and started licking shortly after this deflection. They found that both dSPNs and iSPNs were depolarized in response to this whisker stimulation, with dSPNs exhibiting a more rapid depolarization than iSPNs. This approach provided direct electrophysiological evidence linking this learned motor action to excitatory synaptic input to the DLS and increased our understanding of how synaptic inputs drive