Harms Kimberly J, Rioult-Pedotti Mengia S, Carter D Rosy, Dunaevsky Anna
Department of Neuroscience, Brown University, Providence, Rhode Island 02912, USA.
J Neurosci. 2008 May 28;28(22):5686-90. doi: 10.1523/JNEUROSCI.0584-08.2008.
Experience-dependent regulation of synaptic strength in the horizontal connections in layer 1 of the primary motor cortex is likely to play an important role in motor learning. Dendritic spines, the primary sites of excitatory synapses in the brain, are known to change shape in response to various experimental stimuli. We used a rat motor learning model to examine connection strength via field recordings in slices and confocal imaging of labeled spines to explore changes induced solely by learning a simple motor task. We report that motor learning increases response size, while transiently occluding long-term potentiation (LTP) and increasing spine width in layer 1. This demonstrates learning-induced changes in behavior, synaptic responses, and structure in the same animal, suggesting that an LTP-like process in the motor cortex mediates the initial learning of a skilled task.
初级运动皮层第1层水平连接中依赖经验的突触强度调节可能在运动学习中发挥重要作用。树突棘是大脑中兴奋性突触的主要部位，已知其会响应各种实验刺激而改变形状。我们使用大鼠运动学习模型，通过切片中的场记录和标记棘突的共聚焦成像来检查连接强度，以探索仅通过学习简单运动任务所诱导的变化。我们报告称，运动学习会增加反应大小，同时短暂阻断长时程增强（LTP）并增加第1层中的棘突宽度。这证明了在同一动物中学习诱导的行为、突触反应和结构变化，表明运动皮层中的类LTP过程介导了熟练任务的初始学习。
