Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA; Center for the Neural Basis of Cognition, Carnegie Mellon University and University of Pittsburgh, Pittsburgh, PA 15213, USA.
Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA; Center for the Neural Basis of Cognition, Carnegie Mellon University and University of Pittsburgh, Pittsburgh, PA 15213, USA; Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
Neuron. 2024 Oct 23;112(20):3486-3501.e5. doi: 10.1016/j.neuron.2024.07.022. Epub 2024 Aug 20.
Striatum and its predominant input, motor cortex, are responsible for the selection and performance of purposive movement, but how their interaction guides these processes is not understood. To establish its neural and behavioral contributions, we bilaterally lesioned motor cortex and recorded striatal activity and reaching performance daily, capturing the lesion's direct ramifications within hours of the intervention. We observed reaching impairment and an absence of striatal motoric activity following lesion of motor cortex, but not parietal cortex control lesions. Although some aspects of performance began to recover after 8-10 days, striatal projection and interneuronal dynamics did not-eventually entering a non-motor encoding state that aligned with persisting kinematic control deficits. Lesioned mice also exhibited a profound inability to switch motor plans while locomoting, reminiscent of clinical freezing of gait (FOG). Our results demonstrate the necessity of motor cortex in generating trained and untrained actions as well as striatal motoric dynamics.
纹状体及其主要输入源——运动皮层，负责有目的运动的选择和执行，但它们的相互作用如何指导这些过程尚不清楚。为了确定其神经和行为学的贡献，我们双侧损毁了运动皮层，并每天记录纹状体的活动和伸臂表现，在干预后的数小时内捕捉到了损伤的直接后果。我们观察到，在损伤运动皮层后，伸臂表现受损且纹状体运动活动缺失，但损伤顶叶皮层控制区域则不会。虽然在 8-10 天后，一些行为表现开始恢复，但纹状体的投射和中间神经元动力学并没有——最终进入与持续运动控制缺陷相一致的非运动编码状态。损伤的小鼠在运动时也表现出严重的无法切换运动计划的能力，这让人联想到临床步态冻结（FOG）。我们的结果表明，运动皮层对于产生训练有素和未经训练的动作以及纹状体的运动动力学是必要的。
