Skilled motor behavior requires bihemispheric coordination, and participation of striatal outputs originating from two neuronal groups identified by distinctive expression of D1 or D2 dopamine receptors. We trained mice to reach for and grasp a single food pellet and determined how the output pathways differently affected forelimb trajectory and task efficiency. We found that inhibition and excitation of D1-expressing spiny projection neurons (D1SPNs) have a similar effect on kinematics results, as if excitation and inhibition disrupt the whole ensemble dynamics and not exclusively one kind of output. In contrast, D2SPNs participate in control of target accuracy. Further, ex vivo electrophysiological comparison of naive mice and mice exposed to the task showed stronger striatal neuronal connectivity for ipsilateral D1 and contralateral D2 neurons in relation to the paw used. In summary, while the output pathways work together to smoothly execute skill movements, practice of the movement itself changes synaptic patterns.

熟练的运动行为需要双半球协调，以及来自两个神经元组的纹状体输出的参与，这些神经元组由 D1 或 D2 多巴胺受体的独特表达确定。我们训练老鼠伸手去抓一个食物颗粒，并确定输出路径如何不同地影响前肢轨迹和任务效率。我们发现表达 D1 的多刺投射神经元 (D1SPNs) 的抑制和激发对运动学结果有类似的影响，好像激发和抑制破坏了整个整体动力学，而不仅仅是一种输出。相比之下，D2SPN 参与目标精度的控制。此外，离体幼稚小鼠和暴露于该任务的小鼠的电生理比较显示，同侧 D1 和对侧 D2 神经元的纹状体神经元连接性相对于所用爪子更强。总之，虽然输出通路协同工作以顺利执行技能动作，但动作本身的练习会改变突触模式。