Sibener Leslie J, Mosberger Alice C, Chen Tiffany X, Athalye Vivek R, Murray James M, Costa Rui M
Department of Neuroscience, Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY, USA.
Institute of Neuroscience, University of Oregon, Eugene, OR, USA.
Nat Commun. 2025 Mar 26;16(1):2962. doi: 10.1038/s41467-025-58143-4.
Reaching movements are critical for survival, and are learned and controlled by distributed motor networks. Even though the thalamus is a highly interconnected node in these networks, its role in learning and controlling reaches remains underexplored. We report dissociable roles of two thalamic forelimb circuits coursing through parafascicular (Pf) and ventroanterior/ventrolateral (VAL) nuclei in refining reaches to a spatial target. Using 2-photon calcium imaging as mice learn directional reaches, we observe high reach-related activity from both circuits early in learning, which decreases with learning. Pf activity encodes reach direction early in learning, more so than VAL. Consistently, bilateral lesions of Pf before training impairs refinement of reach direction. Pre-training lesions of VAL does not affect reach direction, but increases reach speed and target overshoot. Lesions of either nucleus after training does not affect the execution of learned reaches. These findings reveal different thalamic circuits governing distinct aspects of learned reaches.
伸手够物动作对生存至关重要，且由分布式运动网络学习和控制。尽管丘脑是这些网络中高度互联的节点，但其在学习和控制伸手够物动作方面的作用仍未得到充分探索。我们报告了两条通过束旁核（Pf）和腹前/腹外侧核（VAL）的丘脑前肢回路在将伸手够物动作精确到空间目标方面的不同作用。在小鼠学习定向伸手够物动作时使用双光子钙成像技术，我们观察到在学习早期这两条回路都有与伸手够物高度相关的活动，且随着学习活动减少。Pf活动在学习早期编码伸手够物方向，比VAL更明显。一致地，训练前Pf的双侧损伤会损害伸手够物方向的精确性。训练前VAL的损伤不影响伸手够物方向，但会提高伸手速度和超过目标的程度。训练后任一核团的损伤都不影响已学习的伸手够物动作的执行。这些发现揭示了不同的丘脑回路控制已学习的伸手够物动作的不同方面。
