PDF(Pubmed)
Abstract：
Why does unilateral deep brain stimulation improve motor function bilaterally? To address this clinical observation, we collected parallel neural recordings from sensorimotor cortex (SMC) and the subthalamic nucleus (STN) during repetitive ipsilateral, contralateral, and bilateral hand movements in patients with Parkinson\'s disease. We used a cross-validated electrode-wise encoding model to map electromyography data to the neural signals. Electrodes in the STN encoded movement at a comparable level for both hands, whereas SMC electrodes displayed a strong contralateral bias. To examine representational overlap across the two hands, we trained the model with data from one condition (contralateral hand) and used the trained weights to predict neural activity for movements produced with the other hand (ipsilateral hand). Overall, between-hand generalization was poor, and this limitation was evident in both regions. A similar method was used to probe representational overlap across different task contexts (unimanual vs. bimanual). Task context was more important for the STN compared to the SMC indicating that neural activity in the STN showed greater divergence between the unimanual and bimanual conditions. These results indicate that SMC activity is strongly lateralized and relatively context-free, whereas the STN integrates contextual information with the ongoing behavior.
摘要：
为什么单侧脑深部电刺激能改善双侧运动功能?我们收集了同侧重复感觉运动皮质（SMC）和丘脑下核（STN）的平行神经记录，对侧,帕金森病患者的双侧手部运动。我们使用交叉验证的电极编码模型将肌电图数据映射到神经信号。STN编码运动中的电极在两只手的可比水平上，而SMC电极显示强烈的对侧偏置。为了检查两只手的代表性重叠，我们使用一种情况(对侧手)的数据对模型进行了训练,并使用训练后的权重来预测另一只手(同侧手)产生的运动的神经活动.总的来说,手间的概括很差，这种限制在两个地区都很明显。使用类似的方法来探测不同任务上下文中的代表性重叠(单手与双意)。与SMC相比，STN的任务上下文更为重要，这表明STN中的神经活动在单手和双手条件之间显示出更大的差异。这些结果表明，SMC活动是强烈的横向化和相对无上下文，而STN将上下文信息与正在进行的行为集成在一起。
